Standardized uptake value Standardized uptake value SUV is defined as the decay-corrected tissue concentration of the tracer in a specific region of interest on the PET image divided by the injected activity and then divided again by body weight (or lean body weight or body surface area). https://www.sciencedirect.com › standardized-uptake-value
Standardized Uptake Value – an overview | ScienceDirect Topics
(SUV) is a semiquantitative measurement of uptake in tissue. Many factors affect the SUV, including accuracy of dose calibration, time between injection and imaging (dose to scan time), patient weight (changes are common in oncology patients), motion artifacts, and blood glucose levels.
Monthly Quantitative Accuracy Check – PET scans that are done for evaluation of different cancers are reconstructed, and the pixel values in some cases may be converted to SUV. It is common for physicians to report changes in these values from one scan to the next as indicative of progression or regression of disease.
- It is important that the SUV values generated by the scanner are consistent from scan to scan.
- Drift in the electronics of the scanner can result in discordance between the calibration factor and patient data.
- One method of verifying the SUV is to image a uniform distribution of known radioactivity concentration.
The phantom is imaged using clinical scan parameters. The amount of activity in the phantom and the mass of the phantom are entered into the acquisition data as if it were a patient. When these data are reconstructed, the average SUV value in each reconstructed slice is determined.
The resultant average SUV should be 1.0 ± 10%. Values outside this range would indicate that the scanner should be recalibrated. This test uses the methodology for calibrating the scanner as a check of the calibration. It has the advantage that, if necessary, the phantom is ready to be used for recalibration of the scanner.
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What is maximum SUV in a PET scan?
Role of SUV(max) obtained by 18F-FDG PET/CT in patients with a solitary pancreatic lesion: predicting malignant potential and proliferation – PubMed Objectives: Maximum standardized uptake value (SUV(max)) is a marker of tumor glucose metabolism detected by -fluorodeoxyglucose ((18)F-FDG) PET/computed tomography (PET/CT) and reflects tumor aggressiveness. The aim of the study was to evaluate the value of SUV(max) in differentiating benign from malignant solitary pancreatic lesions and explore the correlation between SUV(max) and tumor proliferative activity. Materials and methods: F-FDG PET/CT scans were performed in 80 patients with solitary pancreatic lesions who were scheduled for resective surgery. The relationships between SUV(max) and postoperative pathologic diagnosis, histologic grade, and Ki-67 proliferation index (PI) were analyzed. Results: Of these 80 patients, 54 had malignant lesions. The SUV(max) of malignant tumors (6.3 ± 2.4) was significantly greater than that of benign lesions (2.9 ± 2.0) (P<0.001). Receiver-operating characteristic curve analysis showed that the SUV(max) cutoff value of 3.5 had a high sensitivity (92.6%) and specificity (76.9%) for the diagnosis of malignancies. Among pancreatic cancers with low (Ki-67<5%), moderate (5% ≤ Ki-67<50%), and high (Ki-67 ≥ 50%) PI, SUV(max) increased significantly from 4.2 ± 1.2, through 6.0 ± 1.7, to 8.6 ± 2.5 (P<0.001). The SUV(max) had a positive correlation with Ki-67 PI (P<0.001, r=0.60). Conclusion: The SUV(max) of F-FDG PET/CT can be used in the differential diagnosis of solitary pancreatic lesions and can also aid in the prediction of proliferative activity of pancreatic cancer. : Role of SUV(max) obtained by 18F-FDG PET/CT in patients with a solitary pancreatic lesion: predicting malignant potential and proliferation - PubMed
What SUV max values are cancerous?
Standardized Uptake Value (SUV) – The standardized uptake value (SUV) is a dimensionless ratio used historically by nuclear medicine professionals to distinguish between “normal” and “abnormal” levels of uptake. It is defined as the ratio of activity per unit volume of a region of interest (ROI) to the activity per unit whole body volume and is considered to be a semi-quantitative parameter.74, 75 It was designed to be a simplistic method to quantify uptake as opposed to true quantification through compartmental and kinetic modeling. An SUV of 2.5 or higher is generally considered to be indicative of malignant tissue; however, there has been a wide range of SUVs reported for similar diseases. Table 4-2 summarizes some of these reported values.74 It is important to recognize that an SUV around 2.5 can be measured in non-malignant regions. Conversely, small tumors can also exhibit maximum SUV of < 2.5. The SUV was created to determine whether a region may be considered "tumor" or "malignant" but may have limited value for determining the edges of a tumor. SUV has a number of limitations, many of which will be mentioned but are beyond the scope of this chapter to discuss in depth. SUV is dependent on many patient-related factors including the ROI defined, the activity injected, plasma glucose levels, competition with endogenous glucose, rate of phosphorylation, body size and body composition, as well as tumor type. Technically, SUV values will vary depending on the PET scanner's signal-to-noise properties, the accuracy of the image reconstruction algorithm as well as corrections algorithms, and the time between injection and image acquisition.75 Not accounting for all these error sources can lead to potential errors of ≥50% in SUV calculations.75 While one would seldom question the interpretation of regions with very high SUVs, uncorrected errors in marginal SUVs (e.g., those in the range of 2.5) could potentially have a large impact on the interpretation of this value. Unfortunately, it is this range of 2.5 that has been proposed as a possible threshold for target localization. This value is based on the diagnostic criteria used to determine if the region of interest may be considered malignant or not. SUVs have been used in delineation of GTVs for esophageal, lung, and head and neck tumors.65, 76, 77 For tumors within the lung, respiratory motion can be a major source of error in SUV values when combined PET-CT scanners are used and the CT images are used to perform attenuation correction on the PET images. CT acquisition of a tumor can occur in seconds, while PET emission acquisition requires a few minutes. Therefore, an incongruent tumor position during CT will bias activity estimates (i.e., SUV calculation) on PET. Using respiratory-gated CT and PET acquisitions, Erdi and colleagues have demonstrated that SUV can vary up to 30% and a tumor position can vary by up to 9 mm on the resultant CT-attenuation-corrected PET image depending on the respiratory phase.46 For diagnosis, SUV has been useful for determining whether or not an area of uptake should be reported as suspicious for malignancy. However for defining the edges of a radiation target, the use of SUV is limited and uncertain. More sophisticated segmentation techniques are required if accurate and consistent targets are to be segmented from PET-CT images. Further developments in the area of quantitative segmentation of PET images for radiation targeting will be essential if the information offered by PET images is to be used in an optimal fashion. The uncertainty associated with the question "what volume should be defined" can be large as has been demonstrated by Nestle and colleagues in a recent paper that compared the volumes defined using different methods of segmentation on PET images from a group of 25 patients with NSCLC.77 Table 4-3 compares the volumes obtained for GTV using four different methods of image segmentation: visual (GTV vis ), applying an isocontour corresponding to an SUV of 2.5 (GTV 2.5 ), applying a threshold of 40% relative to SUV max (GTV 40 ), and lastly, an in-house algorithm based on background intensities (GTV bg ). As an example, the volumes for patient 4 ( Table 4-3 ), who had a clearly CT-defined tumor, were 164.2, 151.1, 56.2, and 82.0 mL, for GTV vis, GTV 2.5, GTV 40, and GTV bg, respectively. The largest volume was approximately three times that of the smallest. The comparisons suggest that differences correlated with SUV max, lesion size, and in particular, tumor inhomogeneity.77 However, without histopathologic correlation, it is unclear which quantity, if any, best represents the true GTV. Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9781416032243500074
What is the highest SUVmax?
Abstract – Objective: The purpose of this study was to assess degree of tumour uptake measured by SUV max in predicting overall survival in patients diagnosed mainly with NSCLC and had baseline pre-treatment PET/CT for staging. Methods: A total of 103 patients (median age 71 years, 53 male and 50 female) diagnosed with different histological types of lung cancer and had variant TNM staging. All patients underwent pre-treatment PET/CT for staging between 2006 and 2017. SUV max was used as a semi-quantitative method to assess tumour activity. Overall survival was estimated using the Kaplan-Meier analysis and Cox regression models. Results: Total 103 patients were enrolled into this study. Median overall survival for all 70 died patients was 11.90 months (range 1.3- 107.7 months; mean ± SD=19.6 ± 21.2 months). The median follow up for 33 alive patients was 87.50 months. Lowest SUVmax was 1.2; highest value was 36.6; (Mean ± SD) SUVmax was 13.7± 6.7 and median SUVmax value was 13.11. Histopathology*SUVmax (HR 2.40; P-value <0.009), size*age (HR 2.362; P-value <0.001), and size*treatment (HR 3.54; P-value <0.000) were found to be independent parameters for overall survival by interactive multivariate analysis, while tumour stage and performance status were not. Conclusion: High FDG tumour activity of a primary lung cancer in pre-treatment PET scan measured by SUV max was significantly associated with poor overall survival in patients mainly diagnosed with NSCLC. Maximum standard uptake value of primary lung cancer might be a sensitive tool for predicting overall survival in lung cancer patients.
Lung cancer Diagnosis
Footnotes Cite this article as: European Respiratory Journal 2019; 54: Suppl.63, PA3043. This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
Copyright ©the authors 2019
What size SUV is a tumor?
Results – Forty patients (9 females and 31 males) were included in this study. Their ages ranged from 35 to 88 years with a median of 63.5 years, an IQR of 57–70 years and a mean (± standard deviation) of 62.95 years (± 10.01 years). The number of males was significantly higher than the number of females in this study ( x 2 = 12.1, P = 0.0005). A 55-year-old male patient whose CT chest revealed multiple pulmonary masses, underwent (FDG) PET/CT scan. (Fig.1 ). A – C (FDG) PET/CT, A Axial view: A large infiltrative metabolically active right lung upper lobe soft tissue mass lesion measures 7.4 × 12 × 8.5 with max.SUV ~ 19.15.
A 57-year-old male patient whose prior chest CT revealed a large pulmonary mass. (Fig.2 ). A–D (FDG) PET/CT. A axial view: A large metabolically active right lower lobe posterior segment mass lesion is noted measuring about 6.73 × 5.45 cm eliciting metabolic activity of max.SUV ~ 19.1.
- Irregular surrounding atelectasis and associated overlying pleural thickening/infiltration.
- B Metabolically active aortocaval, portohepatic lymphadenopathy with max.SUV ~ 11.69.
- C Left adrenal metabolically active lesion with max.SUV ~ 7.9.
- D Full-body coronal MIP PET showing the primary lung mass and lymph nodes with adrenal metastasis.
The tissue sampling was obtained via endoscopic biopsy proved to be squamous cell carcinoma (SCC) Fig.3 A 61-year-old female patient who presented with hemoptysis and bony aches, underwent (FDG) PET/CT imaging. (Fig.3 ). A – D (FDG) PET/CT. A Axial view: Right apical spiculated metabolically active pulmonary mass lesion measuring 3.6 × 3.5 cm with max.SUV ~ 15.4.
66-year-old gentleman with recent bronchoscopy showing a right bronchial mass lesion. (Fig.4 ). A – B (FDG) PET/CT. A Metabolically active large right lower lobe central peribronchial soft tissue mass lesion (arrow) is seen cuffing the left lower lobe bronchus with consequent narrowing of its lumen, the lesion measures about 74 × 44 mm and showing max.SUV ~ 17.
- B Full-body coronal MIP PET showing the primary lung mass with no other distant metastasis.
- The tissue sampling proved to be undifferentiated large cell carcinoma Histopathological analysis of the primary lung tumors revealed the presence of 25 (62.5%) adenocarcinomas, 12 (30%) squamous cell carcinomas (SCC) and 3 (7.5%) large cell carcinomas.
Tumor size ranged from 1.9 to 16.5 cm with a median size of 4.85 cm, an IQR of 3.2–6.45 cm and a mean (± SD) size of 5.21 cm (± 2.64 cm). Primary tumor max.SUV values ranged from 4.5 to 25 with a median of 15.6, an IQR of 9.9–17.6 and a mean (± SD) of 14.1 (± 5.45).
- As regards the (T) staging of the lung tumors, 9 (22.5%), 11 (27.5%), 14 (35%) and 6 (15%) masses were T1, T2, T3 and T4, respectively.
- Regarding the lymph node staging of the patients, 9 (22.5%), 5 (12.5%), 14 (35%) and 12 (30%) patients were N 0, N 1, N 2 and N 3, respectively.
- Regarding the metastatic staging of the patients, 10 (25%), 7 (17.5%), 8 (20%), and 15 (37.5%) patients were M 0, M 1a, M 1b and M 1c, respectively.
Table 1 shows the descriptive data of the whole study population. Table 1 Descriptive data of the whole study population Comparison of tumor max.SUV between males and females revealed no significant difference in SUV values of both groups ( P = 0.66).
Patients were divided into two groups according to age using the median value of 63.5 years. No significant difference was found between the max.SUV values of both groups ( P = 0.64). Comparison of tumor max.SUV between the different tumor histological types revealed that the max.SUV of the squamous cell carcinoma group was significantly higher than that of adenocarcinoma and large cell cancer groups ( P = 0.000009), whereas no significant difference existed between the SUV values of the adenocarcinoma and large cell cancer groups (Table 2 ).
Table 2 Comparison of max.SUV in patient groups designated according to the histopathology of the primary lung tumor Patients were divided into two groups according to size of the primary tumor using the median value of 4.85 cm. Max.SUV was significantly higher in the group whose tumor size was larger than 4.85 cm ( P = 0.01).
When patients were classified into two groups determined by the presence and absence of lymph node metastasis, no significant difference was found between the max.SUV of both groups ( P = 0.63) (Table 3 ). Furthermore, no significant difference was seen in max.SUV of all groups when patients were categorized according to their specific lymph node stage ( N 0, N 1, N 2, N 3) ( P = 0.91).
Table 3 Comparison of max.SUV in patients with and without lymph mode metastasis When patients were classified into two groups determined by the presence and absence of distant metastasis, no significant difference was found between the max.SUV of both groups ( P = 0.46) (Table 4 ).
- Furthermore, no significant difference was seen in max.SUV of all groups when patients were categorized according to their specific distant metastasis stage ( M 0, M 1a, M 1b, M 1c) ( P = 0.12).
- Table 4 Comparison of max.SUV in patients with and without distant metastasis A significant positive correlation was found between the primary tumor max.SUV and tumoral size ( r s = 0.54, P = 0.0003), as shown in scatter diagram of (Fig.5 ).
Fig.5 Scatter diagram displaying the positive correlation between tumor max.SUV and tumor size in all patients A negative statistically insignificant correlation was found between tumoral max.SUV and the age of patients ( r s =− 0.09, P = 0.598), as shown in scatter diagram of (Fig.6 ). Fig.6
Scatter diagram displaying insignificant correlation between tumor max.SUV and the age of patients
Do benign tumors light up on PET scan?
This type of scan help determine whether a smaller spot is cancerous or benign, as cancerous lesions are much more likely to light up on a PET scan than benign spots or scar tissue.
What is the normal SUV range on a PET scan for lymph nodes?
Discussion – In keeping with published reports, the SUVmax of the primary tumor was significantly higher in the SCC group (11.0 ± 4.1) than in the AC group (7.4 ± 4.4), Although the uptake mechanism and biochemical pathways of FDG are not completely understood, previous studies showed that glucose transporters (Gluts) are important factors that influence FDG uptake by malignant tumors and that Glut-1 is the principal subtype in NSCLC. It was reported that the degree of Glut-1 expression in SCC is higher than that in AC, which may partly explain why the SUVmax of SCC is higher than that of AC FDG uptake and PCNA, Glut-1, and Hexokinase-II expressions in cancers and inflammatory lesions of the lung. Neoplasia.2005;7:369–79.” href=”https://localhost/articles/10.1186/s12890-015-0014-2#ref-CR20″ id=”ref-link-section-d82048429e1841″>20 ]. It also has been reported that the SUVmax of NSCLC is positively correlated with tumor size. In our study, we found that the primary tumor size of SCC was significantly greater than that of AC, which could be another cause of the higher tumor SUVmax in the SCC group. Although it is indicated that the SUVmax of SCC is higher than that of AC, it still remains unclear whether the SUVmax of metastatic lymph nodes in SCC patients is also higher than that in AC patients. Our study showed that there was no difference in the SUVmax of metastatic lymph nodes between the SCC (4.6 ± 3.1) and AC groups (3.6 ± 2.5). This result demonstrated that the histological type of NSCLC does not affect the SUVmax of metastatic lymph nodes even though it influences the SUVmax of the primary tumor. In this study, multivariable linear regression revealed that the SUVmax of metastatic lymph nodes had a positive correlation with lymph node size, but the SUVmax and size of the primary tumor, location of the primary tumor, and tumor differentiation had no influence on the SUVmax of metastatic lymph nodes. This result indicates that the size of the lymph nodes may be the key factor that affects the SUVmax of metastatic lymph nodes. Our study also showed that when the short-axis diameter of the lymph node was 15 mm. Bille et al. analyzed the factors associated with metastatic lymph node detection in patients with AC vs. SCC, and they found that in the AC group, the mean diameter of false-negative lymph nodes was 7 ± 2.5 mm, compared with the 12.5 ± 4 mm diameter of true-positive lymph nodes. In the SCC group, the mean diameter of false-negative lymph nodes was 7.4 ± 2.8 mm, compared with the 14.7 ± 6 mm diameter of true-positive lymph nodes. Regarding nodal size, the PET-CT sensitivity in detecting malignant involvement was 32.4% in nodes 15 mm in both SCC and AC. Nambu et al. found that lymph node metastases were more commonly observed in NSCLC cases with a higher tumor SUVmax. The frequency of lymph node metastases was 70% in NSCLC patients with a tumor SUVmax greater than 12, whereas no lymph node metastases were found in NSCLC patients with a tumor SUVmax less than 2.5. These results suggest that lung cancer patients exhibiting a high tumor SUVmax may have a high risk for lymph node metastases. Similar results have also been reported in other studies FDG uptake is an independent predictive factor for regional lymph node metastasis in patients with non-small cell lung cancer. Cancer Imaging.2013;12:566–72.” href=”https://localhost/articles/10.1186/s12890-015-0014-2#ref-CR23″ id=”ref-link-section-d82048429e1859″>23 ]. However, our study revealed that there is no correlation between the SUVmax of the primary tumor and the SUVmax of the metastatic lymph node, which may due to the smaller sample size in our study. In clinical practice, it is challenging to distinguish metastatic lymph nodes from benign lymph nodes, especially for those lymph nodes with a short-axis diameter of less than 10 mm, which are always classified as negative for metastasis before surgery. According to the studies mentioned above, we believe that those lymph nodes with a short-axis diameter less than 10 mm should not be classified as negative despite having a SUVmax score of less than 2.5. If those small size lymph nodes have a higher primary tumor SUVmax, there is a high probability of metastasis, and further invasive procedures such as EBUS-TBNA, mediastinoscopy or VATS may be considered. Previous studies indicated that PET-CT has a low sensitivity and a relatively high specificity for detecting thoracic lymph node metastases. However, to date, the ideal SUVmax cut-off for distinguishing malignant from benign thoracic lymph nodes has not been determined. Most studies have defined a SUVmax of 2.5 as the upper limit of normal lymph nodes. However, this cut-off is purely arbitrary. Some previous studies also considered positive mediastinal lymph nodes to be nodes that exhibit focally increased 18-FDG uptake above the normal background activity. In our study, we found that using the SUVmax cut-off of 2.5 resulted in a considerable number of false negatives for pathologically metastatic lymph nodes. In order to determine whether the sensitivity could be improved by adjusting the criteria, we compared the sensitivity, specificity and accuracy of PET-CT in detecting metastatic lymph nodes using two different SUVmax cut-offs. Our study showed that there was no significant difference in the specificity and accuracy of the two criteria in either the SCC or AC group. The sensitivity in the AC and SCC groups detected using criterion 1 was significantly higher than that using criterion 2. The different SUVmax cut-offs significantly affected the sensitivity but not the specificity. Therefore, we suppose that a SUVmax cut-off value of 2.5 for detecting metastatic lymph nodes may not be optimal for sensitivity because lymph nodes with a slight SUVmax increase may be associated with a missed diagnosis. Bille et al. assessed the sensitivity, specificity and accuracy of PET-CT for detecting lymph node metastasis in different histological types of NSCLC; lymph nodes were deemed positive for metastatic spread if they exhibited focally increased FDG uptake that was higher than the normal background activity, The study showed that the sensitivity, specificity and accuracy of PET-CT were 53.8, 91.5 and 79.1%, respectively, in the AC group and 87.5, 81.8 and 83.5%, respectively, in the SCC group. Although the sensitivity may be increased when lymph nodes are defined as malignant when their SUVmax is higher than the background, this scenario will also increase the possibility of a false positive result. Therefore, the results of this preliminary study need to be confirmed. Our study has several limitations. First, this study was retrospective in design, and there may have been bias. Second, this study examined a limited number of patients, and the study population consisted of only patients who underwent surgery; thus, a definitive conclusion cannot be drawn.
What size tumor is detected by PET scan?
PET Scan – The positron emission tomography (PET) scan creates computerized images of chemical changes, such as sugar metabolism, that take place in tissue. Typically, the patient is given an injection of a substance that consists of a combination of a sugar and a small amount of radioactively labeled sugar.
- The radioactive sugar can help in locating a tumor, because cancer cells take up or absorb sugar more avidly than other tissues in the body.
- After receiving the radioactive sugar, the patient lies still for about 60 minutes while the radioactively labeled sugar circulates throughout the body.
- If a tumor is present, the radioactive sugar will accumulate in the tumor.
The patient then lies on a table, which gradually moves through the PET scanner incrementally several times during a 15-60-minute period. The PET scanner is used to detect the distribution of the sugar in the tumor and in the body. By the combined matching of a CT scan with PET images, there is an improved capacity to discriminate normal from abnormal tissues.
A computer translates this information into the images that are interpreted by a radiologist. PET scans may play a role in determining whether a mass is cancerous. However, PET scans are more accurate in detecting larger and more aggressive tumors than they are in locating tumors that are smaller than 8 mm a pinky nail (or half of a thumb nail) and/or less aggressive cancers.
The size of smallest tumor mass that can be found at PET is constantly improving. They may also detect cancer when other imaging techniques show normal results. PET scans may be helpful in evaluating and staging recurrent disease (cancer that has come back). PET scans. Uptake of tracer in the lymph nodes involved with lymphoma in the groin, both axilla, and neck (red areas). Image coutesy of Dr. Jorge Carrasquillo, Nuclear Medicine Department, Clinical Center, National Institutes of Health.
What is the SUV range for PET scan lymphoma?
In patients with indolent lymphoma, the SUV ranged from 2.3 to 13.0 (mean, 6.7; SD, 2.9). In patients with aggressive lymphoma, SUV ranged from 3.2 to 43.0 (mean, 17.2; SD, 9.7; P
What is normal SUV range for lungs?
Abstract – 1298 Objectives: To help establish normal reference values for PET oncology studies of the thorax and abdomen, this retrospective study was undertaken to define normal SUVs for both liver and lung tissue, with attention given to the age of the patient.
- Although FDG uptake in breast tissue has been studied in relation to age, there have been no known studies to examine if FDG uptake within normal lung or liver varied with age in relation to age of the patient.
- Methods: Retrospective analysis of hand drawn region of interest measurements taken from the lower and mid lung fields in the axial plane were studied in relation to age for 109 cases (injected FDG dose:370 MBq; scanner : Positron HZL ) Mean SUV for the lung were plotted in relation to age in years; right and left lung SUV values were averaged to generate one value per patient per study.
Liver mean SUV measurements were taken from normal appearing right lobe of the liver in 139 cases, and graphed in relation to age. Results: The average mean SUV from normal lung tissue was 0.45 (n=109) with no significant correlation to age found in this group where most patients were between 40 and 85 years.
A weighted average calculation including the data from two previously published studies from other labs show the average mean SUV of normal lung parenchyma to be 0.52 (n=279). In contrast to the lung parenchyma, normal appearing liver had a higher and more heterogeneous pattern of uptake with the average mean SUV equaling 1.55 (n=139).
Normal lung to normal liver mean SUV values averaged 0.27 (n=99). No significant correlation was seen between age age and normal liver FDG uptake was noted. When including the mean liver SUVs from three other published cases from different labs, a weighted average for normal liver SUV was found to be 2.16 for an aggregate total of 389 cases.
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What is SUV of 10 on a PET scan?
Move beyond lesion counting and size measurement to lesion characterisation – The classical PET/CT indications involve primary staging, therapeutic monitoring, detection of recurrence disease or surveillance. The ability to non-invasively measure glycolytic activity, defining what we refer to as the “metabolic signature”, however, is a key feature of FDG PET/CT that is overlooked by many reporters.
For the majority of malignant processes, the intensity of metabolic abnormality correlates with degree of aggressiveness or proliferative rate. For a metastatic malignant process that demonstrates no or minimal metabolic abnormality, this is usually a marker of low proliferative rate and indolent phenotype.
Medical Terminology: Suffixes MADE EASY [Nursing, Students, Coding]
Applying conventional diagnostic imaging paradigms, a negative PET/CT study in a patient with biopsy proven malignancy would be considered false-negative. A more useful report, however, would highlight the powerful prognostic information this provides.
Providing such prognostic information was formerly the domain of pathology; a report which ignores the intensity of metabolic abnormality is missing a key utility of FDG PET/CT. Descriptively, we define SUV 15 as “very intense”. Documenting the actual SUV in the report can be useful to avoid ambiguity with qualitative statements that may be interpreted variably.
Evolving literature suggests that intensity of uptake is an independent prognostic factor and in some tumour subtypes superior to histopathologic characterisation. Tumours with low uptake and commensurate indolent phenotype may include papillary thyroid cancer, neuroendocrine tumours, clear cell renal carcinomas and breast carcinoma.
Each of these, however, can also demonstrate high intensity uptake commensurate with their spectrum of well- to poorly-differentiated phenotype, with the more aggressive phenotypes demonstrating high intensity uptake commensurate with their higher proliferative rate. PET can be used to guide targeted biopsy of the most intense site of metabolic activity.
There are some important exceptions to this broad principle as detailed below:
What is the SUV max for lymph nodes?
Evaluation of the lymph nodes – A total of 334 mediastinal and hilar lymph node stations were evaluated. Among them, there were 100 lymph node stations showing higher FDG uptake than the surrounding mediastinal blood pool (SUVmax range: 1.57-24.75, median: 3.15, mean ± SD: 3.57 ± 2.45) on PET/CT.
- Fourteen (14%) of them were due to metastasis, 39 (39%) reactive, 40 (40%) anthracosis, 4 (4%) granulomatosis and 3 (3%) silicosis.
- All of the metastatic lymph node stations (10 mediastinal, 4 hilar) had a SUVmax ≥2.5.
- Twenty-four patients (29.6%) had metastatic interlobar or intrapulmonary lymph nodes that could not be identified on PET/CT because of close relationship with the primary tumor.
PET/CT evaluation and the presence of metastasis in the mediastinal and hilar lymph node stations are shown in Table 5, The sensitivity, specificity, and accuracy of PET/CT for the staging of mediastinal and hilar lymph nodes were 63.6%, 72.4%, and 71.8% respectively.
What is SUV max range for breast?
Discussion – We investigated correlations between SUVmax and clinicopathological features in luminal-type breast cancer. SUVmax was correlated with lymphatic invasion, nuclear grade, lymph node metastasis, and Ki-67 LI. Regarding the correlation with Ki-67 LI, a meta-analysis suggested that SUVmax was correlated with Ki-67 LI in various cancers ( 4 ), with a correlation coefficient of 0.29–0.56 for breast cancer ( 5 – 7 ). However, in these prior studies, no distinction between ER-positive and ER-negative breast cancer was observed. Cheng et al. ( 7 ) reported a correlation coefficient of 0.23 between SUVmax and Ki-67 LI in ER-positive breast cancer compared with a value of 0.67 in the present study. The difference between the correlation values in Cheng et al. ‘s report and the present study could be because of the difference in the number of patients enrolled in each study. Moreover, Cheng et al. ‘s study included patients with stage IV breast cancer, while our study did not. Therefore, if analyses were limited to luminal breast cancer while excluding stage IV breast cancer, Ki-67 LI could be correlated with SUVmax. In contrast, as we previously reported ( 8 ), Ki-67 LI values are slightly variable. Depending on the tissue used (either from needle biopsy or taken during surgery) and the site of tissue to be evaluated, Ki-67 LI varied; furthermore, Ki-67 LI also differed among facilities. Therefore, analyzing the correlation between Ki-67 LI and SUVmax has some limitations. To provide individualized medical treatment for breast cancer, considerable efforts regarding immunostaining are required ( 9 ). Indications for adjuvant chemotherapy for luminal-type breast cancer are difficult to determine, with no defined consensus yet. The 12th St. Gallen Consensus Conference regarding early breast cancer announced that the status of PgR, Ki-67, lymph node metastasis, or nuclear grade should be used as indications for adjuvant chemotherapy. This can be a serious problem in countries, such as Japan, where there is an insufficient number of pathologists. Therefore, it can be beneficial to use imaging diagnostics in lieu of immunostaining. In Japan, there are only 1.0 pathological specialists per 100,000 population, or 0.5% of all doctors. This is only 20% of the relative number compared to that in the US. Because of this limitation, we examined whether imaging diagnosis could replace pathological diagnosis such as Ki-67 LI, PgR status, or nuclear grade. Therefore, we investigated whether SUVmax could be used to help classify patients with and without an indication for adjuvant chemotherapy. When we constructed a ROC curve depending on SUVmax, the area under the curve was 0.753, and at a cutoff SUVmax of 3.51, the sensitivity and specificity were 66.0% and 73.1%, respectively. Therefore, imaging diagnosis was useful, but the sensitivity and specificity were not satisfactory; thus, further improvement is necessary. For example, Yamane et al. ( 10 ) reported that findings on 18 F-fluorothymidine PET showed better correlation with the immunohistochemical index of cell proliferation in leiomyoma compared with those on 18 F-FDG PET. In addition, because SUV is related to cell density, analyses should be performed based on histological type. However, this was not possible in the present study owing to the small sample size. Moreover, SUV is affected by tumor size. Because of the partial volume effect, it is not possible to obtain an accurate count in a small lesion, and the SUV is underestimated. Calculating the recovery count in the phantom experiment makes it possible to correct the partial volume effect. However, we do not employ phantom experiments in our facility. Therefore, the use of phantom experiments to assist with obtaining more accurate SUV measurements remains to be explored. In recent years, a method to determine the degree of malignancy in breast cancer based on genetic assays, such as the 21-gene recurrence score, has been developed; however, this is not yet available at our hospital, and thus, the indication for chemotherapy depends only on pathological information only. Therefore, for luminal-type breast cancer, the indication included PgR negativity, Ki-67 LI >14%, nuclear grade of 3, or lymph node metastasis-positive. In our study, the SUVmax cutoff value of indication for chemotherapy was set to 3.5. On the other hand, Ahn et al. ( 11 ) previously reported that in ER-positive, HER2-negative breast cancer, SUVmax ≥4 was independently associated with a 21-gene recurrence score ≥26, which was considered as a recommendation to undergo adjuvant chemotherapy. In addition, a study by Kitajima et al. ( 12 ) reported the prognostic value of SUVmax in breast cancer using a cutoff SUVmax of 3.6; an SUVmax of 3.5–4 was considered to indicate highly malignant breast cancer. This study had several limitations. First, the study population was small, and the study design was retrospective. A larger study population and additional outcome data are needed to confirm our results. Second, the usefulness of metabolic tumor volume and total lesion glycolysis have been reported ( 13 ); however, these are not calculated at our hospital. Third, the relationship between SUVmax and prognosis is not clear, because no patient showed relapse due to the short duration of follow-up. In conclusion, SUVmax of 18F-FDG PET could replace pathological diagnosis in luminal breast cancer.
What is considered a high SUV uptake?
The standardized uptake value (SUV) is a semiquantitative means for determining the relative degree of metabolism in a lesion. An SUV greater than 2.5 is highly suggestive of a malignant lesion, whereas lesions with an SUV less than 2.5 are frequently benign.
What is the average mass of a SUV?
Average Vehicle Weight – Vehicle weight depends on the model, year of manufacture, materials used, and car type. While each automobile type (SUVs, EVs, trucks, etc.) can significantly vary in poundage, statistics help determine the averages. According to EPA’s (Environmental Protection Agency) data, the average weight of an automobile in 2022 was around 4,094 pounds, which is only a slight increase compared to 2018’s 4,000 pounds.
But if you want to go into specifics, there are estimated averages sorted by type. Small autos usually way around 2,500 pounds and large automobiles about 4,200 pounds. SUVs or trucks can range from 3,500 pounds to over 6,000 pounds. These numbers, however, are not definitive and heavily depend on the model you’ve got.
Because they are inaccurate, you should always check and find your vehicle’s exact poundage. And while we’ll get to the benefits of this knowledge in a bit, you should also distinguish between the different types of weight. Local Deals & Incentives If you are in the market for a new car we can help you find local deals and the latest incentives from dealers in your area.
Does tumor size indicate stage?
The stage of a cancer describes the size of a tumour and how far it has spread from where it originated. The grade describes the appearance of the cancerous cells. If you’re diagnosed with cancer, you may have more tests to help determine how far it has progressed. Staging and grading the cancer will allow the doctors to determine its size, whether it has spread and the best treatment options.
Is a biopsy better than a PET scan?
PET/CT proves more accurate than marrow biopsy in diagnosis and prognosis of lymphoma patients – Source: Berthet L, Cochet A, Kanoun S et al. In newly diagnosed diffuse large b-cell lymphoma, determination of bone marrow involvement with 18F-FDG PET/CT provides better diagnostic performance and prognostic stratification than does biopsy.J. Nucl. Med.54(8), 1244–1250 (2013). A recent study published in the Journal of Nuclear Medicine reported that imaging with 18F-fluorodeoxyglucose (FDG) PET/CT was more accurate, demonstrated a higher negative predictive value and was more sensitive than bone marrow biopsy, the current gold standard, for determining bone marrow involvement in sufferers of diffuse large B-cell lymphoma, a key factor in determining treatment strategy. The retrospective study, carried out at the Center Georges-François Leclerc (Dijon, France), included 133 patients referred to the center between June 2006 and October 2011. All patients received both a whole-body PET/CT scan and a bone marrow biopsy to determine marrow involvement. A final diagnosis of bone marrow involvement was made if the biopsy was positive, or if a positive PET/CT result was subsequently confirmed by guided biopsy, targeted MRI or the concomitant disappearance of focal bone marrow uptake with that of uptake in other lymphoma lesions on PET/CT monitoring. Progression-free survival and overall survival were then analyzed. A total of 33 patients exhibited bone marrow involvement; of these, eight were identified by biopsy and 32 were identified by 18F-FDG PET/CT. PET/ CT was more sensitive (94 vs 24%; p < 0.001), demonstrated a higher negative predictive value (98 vs 80%) and was more accurate (98 vs 81%) than the biopsy procedure. Of 24 patients with a positive PET/CT but negative biopsy for bone marrow involvement, 11 were re-evaluated as stage IV, which resulted in a revision of their treatment plans. Furthermore, PET/CT was also determined to be an independent predictor of progression-free, although not overall, survival. Louis Berthet, the lead author, commented: "In our study, we showed that in diffuse large B-cell lymphoma, 18F-FDG PET/CT has better diagnostic performance than bone marrow biopsy to detect bone marrow involvement and provides a better prognostic stratification. While bone marrow biopsy is considered to be the gold standard to evaluate bone marrow involvement in high-grade lymphomas, 18F-FDG PET/CT is in fact the best method to evaluate extension of the disease, as well as avoid invasive procedures." He added, "Our findings add to the literature to prove the significance of 18F-FDG PET/CT in cancer evaluation and to democratize this imaging method. Molecular imaging is the best method to adapt targeted therapies to each patient. The emergence of PET/MRI and novel radiotracers predicts an exciting new future for our field."
Can a PET scan tell if a tumor is malignant or benign?
A PET scan is a test that creates 3 dimensional (3D) pictures of the inside of your body. PET stands for positron emission tomography. The PET scan uses a mildly radioactive drug to show up areas of your body where cells are more active than normal. It’s used to help diagnose some conditions including cancer.
It can also help to find out where and whether cancer has spread. You usually have a PET scan in the radiology or nuclear medicine department as an outpatient. These scanners tend to be only in the major cancer hospitals. So you might have to travel to another hospital to have one. A radiographer operates the scanner.
It usually takes between 45 and 60 minutes. You will be in the department for at least an hour beforehand. This is because you have an injection of a radioactive liquid (radiotracer) before the scan. PET scans are often combined with CT scans to produce more detailed images.
Can you tell if a tumor is benign or malignant from a CT scan?
Can a CT scan detect cancer? – A CT scan, like any imaging tool, cannot detect cancer, though it may be useful in helping to identify a mass and determine its location and size. A CT scan may also offer valuable information, such as its shape and possible makeup (e.g., solid vs.
What is a normal SUV lymph nodes?
Discussion – In keeping with published reports, the SUVmax of the primary tumor was significantly higher in the SCC group (11.0 ± 4.1) than in the AC group (7.4 ± 4.4), Although the uptake mechanism and biochemical pathways of FDG are not completely understood, previous studies showed that glucose transporters (Gluts) are important factors that influence FDG uptake by malignant tumors and that Glut-1 is the principal subtype in NSCLC. It was reported that the degree of Glut-1 expression in SCC is higher than that in AC, which may partly explain why the SUVmax of SCC is higher than that of AC FDG uptake and PCNA, Glut-1, and Hexokinase-II expressions in cancers and inflammatory lesions of the lung. Neoplasia.2005;7:369–79.” href=”https://localhost/articles/10.1186/s12890-015-0014-2#ref-CR20″ id=”ref-link-section-d82048429e1841″>20 ]. It also has been reported that the SUVmax of NSCLC is positively correlated with tumor size. In our study, we found that the primary tumor size of SCC was significantly greater than that of AC, which could be another cause of the higher tumor SUVmax in the SCC group. Although it is indicated that the SUVmax of SCC is higher than that of AC, it still remains unclear whether the SUVmax of metastatic lymph nodes in SCC patients is also higher than that in AC patients. Our study showed that there was no difference in the SUVmax of metastatic lymph nodes between the SCC (4.6 ± 3.1) and AC groups (3.6 ± 2.5). This result demonstrated that the histological type of NSCLC does not affect the SUVmax of metastatic lymph nodes even though it influences the SUVmax of the primary tumor. In this study, multivariable linear regression revealed that the SUVmax of metastatic lymph nodes had a positive correlation with lymph node size, but the SUVmax and size of the primary tumor, location of the primary tumor, and tumor differentiation had no influence on the SUVmax of metastatic lymph nodes. This result indicates that the size of the lymph nodes may be the key factor that affects the SUVmax of metastatic lymph nodes. Our study also showed that when the short-axis diameter of the lymph node was 15 mm. Bille et al. analyzed the factors associated with metastatic lymph node detection in patients with AC vs. SCC, and they found that in the AC group, the mean diameter of false-negative lymph nodes was 7 ± 2.5 mm, compared with the 12.5 ± 4 mm diameter of true-positive lymph nodes. In the SCC group, the mean diameter of false-negative lymph nodes was 7.4 ± 2.8 mm, compared with the 14.7 ± 6 mm diameter of true-positive lymph nodes. Regarding nodal size, the PET-CT sensitivity in detecting malignant involvement was 32.4% in nodes 15 mm in both SCC and AC. Nambu et al. found that lymph node metastases were more commonly observed in NSCLC cases with a higher tumor SUVmax. The frequency of lymph node metastases was 70% in NSCLC patients with a tumor SUVmax greater than 12, whereas no lymph node metastases were found in NSCLC patients with a tumor SUVmax less than 2.5. These results suggest that lung cancer patients exhibiting a high tumor SUVmax may have a high risk for lymph node metastases. Similar results have also been reported in other studies FDG uptake is an independent predictive factor for regional lymph node metastasis in patients with non-small cell lung cancer. Cancer Imaging.2013;12:566–72.” href=”https://localhost/articles/10.1186/s12890-015-0014-2#ref-CR23″ id=”ref-link-section-d82048429e1859″>23 ]. However, our study revealed that there is no correlation between the SUVmax of the primary tumor and the SUVmax of the metastatic lymph node, which may due to the smaller sample size in our study. In clinical practice, it is challenging to distinguish metastatic lymph nodes from benign lymph nodes, especially for those lymph nodes with a short-axis diameter of less than 10 mm, which are always classified as negative for metastasis before surgery. According to the studies mentioned above, we believe that those lymph nodes with a short-axis diameter less than 10 mm should not be classified as negative despite having a SUVmax score of less than 2.5. If those small size lymph nodes have a higher primary tumor SUVmax, there is a high probability of metastasis, and further invasive procedures such as EBUS-TBNA, mediastinoscopy or VATS may be considered. Previous studies indicated that PET-CT has a low sensitivity and a relatively high specificity for detecting thoracic lymph node metastases. However, to date, the ideal SUVmax cut-off for distinguishing malignant from benign thoracic lymph nodes has not been determined. Most studies have defined a SUVmax of 2.5 as the upper limit of normal lymph nodes. However, this cut-off is purely arbitrary. Some previous studies also considered positive mediastinal lymph nodes to be nodes that exhibit focally increased 18-FDG uptake above the normal background activity. In our study, we found that using the SUVmax cut-off of 2.5 resulted in a considerable number of false negatives for pathologically metastatic lymph nodes. In order to determine whether the sensitivity could be improved by adjusting the criteria, we compared the sensitivity, specificity and accuracy of PET-CT in detecting metastatic lymph nodes using two different SUVmax cut-offs. Our study showed that there was no significant difference in the specificity and accuracy of the two criteria in either the SCC or AC group. The sensitivity in the AC and SCC groups detected using criterion 1 was significantly higher than that using criterion 2. The different SUVmax cut-offs significantly affected the sensitivity but not the specificity. Therefore, we suppose that a SUVmax cut-off value of 2.5 for detecting metastatic lymph nodes may not be optimal for sensitivity because lymph nodes with a slight SUVmax increase may be associated with a missed diagnosis. Bille et al. assessed the sensitivity, specificity and accuracy of PET-CT for detecting lymph node metastasis in different histological types of NSCLC; lymph nodes were deemed positive for metastatic spread if they exhibited focally increased FDG uptake that was higher than the normal background activity, The study showed that the sensitivity, specificity and accuracy of PET-CT were 53.8, 91.5 and 79.1%, respectively, in the AC group and 87.5, 81.8 and 83.5%, respectively, in the SCC group. Although the sensitivity may be increased when lymph nodes are defined as malignant when their SUVmax is higher than the background, this scenario will also increase the possibility of a false positive result. Therefore, the results of this preliminary study need to be confirmed. Our study has several limitations. First, this study was retrospective in design, and there may have been bias. Second, this study examined a limited number of patients, and the study population consisted of only patients who underwent surgery; thus, a definitive conclusion cannot be drawn.
What is the SUV range for PET scan lymphoma?
The SUV study – max for a transformed aggressive lymphoma ranged from 3.2 to 40, with a mean of 15 and a median of 12.
What is a normal Deauville score?
Scores of 1 and 2 are considered to be negative and 4 and 5 are considered to be positive. ‘Score 3 should be interpreted according to the clinical context but in many Hodgkin Lymphoma patients indicates a good prognosis with standard treatment.’
What is normal SUV for breast?
The PET/CT tumor SUV max was 1.70, tumor SUV mean was 0.77, and normal breast SUV mean was 1.57.