The measurement of SUVmax of the primary tumor is predictive of prognosis for patients with endometrial cancer

Predictive value of SUVmax from initial 18F-FDG PET/CT scans for treatment outcomes in endometrial cancer patients undergoing fertility sparing management

OBJECTIVE

To evaluate whether the maximum standardized uptake value (SUVmax) from initial 18F-FDG PET/CT (fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography) scans could be a predictor of complete response and recurrence in patients with endometrial cancer who are undergoing fertility sparing management.

METHODS

We conducted a retrospective review of patients who were diagnosed with endometrial cancer through biopsy and chose to undergo fertility sparing management using progestin at the Asan Medical Center, from January 2011 to December 2020. Of these, 113 patients who had an 18-FDG-PET/CT scan before starting treatment were included in our study. We measured SUVmax and examined its correlation with complete response and time to progression after achieving complete response to progestin therapy.

RESULTS

Of 113 patients, 73 (64.6%) achieved a complete response through fertility sparing management. The receiver operating characteristic curve analysis revealed that the optimal cut-off value of SUVmax for predicting complete response was 6.2 (sensitivity 79.5%, specificity 57.5%, p=0.006). After analyzing recurrence in the 73 patients who achieved complete response, we found that patients with an SUVmax value >6.2 had a significantly shorter time to progression compared with those with a value <6.2. (p=0.04).

CONCLUSIONS

SUVmax values of PET-CT, along with other clinicopathological parameters, could be used to predict treatment response and recurrence risk in patients with stage I endometrial cancer undergoing fertility sparing management.

Preoperative 18F-FDG PET/CT in Patients with Presumed Localized Colon Cancer: A Prospective Study with Long-Term Follow-Up

We analyzed whether preoperative 18F-FDG PET/CT adds to conventional primary staging in patients with presumed non-metastatic colonic cancer (CC). The prognostic role of 18F-FDG uptake in the primary tumor was evaluated after a mean follow-up of 15 years. Patients with a new diagnosis of presumed localized CC were prospectively enrolled and underwent presurgical 18F-FDG PET/CT. For each colon lesion, SUVmax, SUVpeak, TLG, and MTV were assessed and tested as prognostic factors. Forty-eight patients were included. Post-surgery pathology identified a total of 103 colon lesions, including 58 invasive adenocarcinomas, 4 in situ adenocarcinomas, 3 adenomas with high-grade dysplasia, and 38 adenomas with low-grade dysplasia. Per lesion sensitivity, specificity, positive (PPVs) and negative predictive values (NPVs) for colonic primary tumor detection were 78%, 97%, 98%, and 73% for conventional workup, and 94%, 87%, 92%, and 89% for 18F-FDG PET/CT. Only sensitivity was significantly different between 18F-FDG PET/CT and conventional workup. PET detected an additional ten pathological colonic lesions in seven patients. SUVmax, SUVpeak, and TLG showed significant differences between invasive adenocarcinomas, in situ adenocarcinomas, and high-grade dysplasia compared to low-grade dysplasia. There was a statistically significant difference between pT1-pT2 and pT3-pT4 adenocarcinomas. On patient-based analysis, sensitivity, specificity, PPV, and NPV for nodal staging were 22%, 84%, 44%, and 65% for CECT, and 33%, 90%, 67%, and 70% for 18F-FDG PET/CT, without a statistically significant difference. PET/CT also identified unknown metastatic spread and one synchronous lung cancer in four patients. Overall, 18F-FDG PETCT had an additional diagnostic value in 11 out of 48 patients (23%). 18F-FDG uptake of the primary tumor did not predict nodal or distant metastases. The difference in disease-free survival categorized by median SUVmax, SUVpeak, TLG, and MTV was not significant. Finally, preoperative 18F-FDG PET/CT is valuable in detecting potential colon lesions not visualized by conventional workups, especially in cases of incomplete colonoscopy. It effectively highlights distant metastases but exhibits limitations for N staging. Mainly due to the relatively small sample size, the quantitative analysis of 18F-FDG uptake in the primary tumor did not reveal any association with recurrence or disease-free survival, adding no significant prognostic information.

Predictive Role of Preoperative Whole-Body 18F-FDG PET/CT for Risk Stratification of Early-Stage (FIGO I-IIA) Cervical Cancer Patients Treated by Surgery

INTRODUCTION

The aim of the present study was to investigate the predictive value of maximum standardized uptake value (SUVmax) measured on preoperative 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) in International Federation of Gynecology and Obstetrics (FIGO 2009) stage I-IIA cervical cancer patients who were treated with radical hysterectomy.

METHODS

A total of 47 patients with FIGO stage I-IIA cervical cancer who were evaluated preoperatively with biopsy and 18F-FDG PET/CT followed by radical hysterectomy were included in the study. Correlation between SUVmax and pathological risk factors or survival was studied.

RESULTS

The mean SUVmax was significantly higher in patients with large tumor size (≥4 cm), advanced stage (IIA>IB>IA) and depth of invasion >50%. No significant difference was noted in SUVmax between patients with and without pelvic lymph node involvement (P=0.639). SUVmax of the primary tumor with and without lymph-vascular invasion were 12.95 and 10.35, respectively (P=0.5). No significant difference was noted between patients with high SUVmax and low SUVmax with regards to overall survival (OS) and disease-free survival (DFS), using an optimal cut-off value of 7.65 for OS and DFS obtained from receiver operating characteristic (ROC) curve analysis. Patient with tumor size >4cm had 5.9 times more probability of mortality compared to tumor size <4cm (P=0.09).

CONCLUSION

The present study observations showed that although SUVmax is associated with pathological variables, it does not independently predict oncological outcomes in FIGO stage IA-IIA cervical cancer patients who were treated with radical hysterectomy. These findings suggest that SUVmax of primary tumor may be used for risk stratification, but not for prognostication in surgically treated early-stage cervical cancer patients. Not using other parameters of 18F-FDG PET/CT like metabolic tumor volume (MTV), tumor lysis glycolysis (TLG), small sample size, variation in calculation of SUVmax, histopathologic heterogeneity, inclusion of stage IA patients in the study were constraints of present study. Further studies with large sample size using multi metabolic parameters of 18F-FDG PET/CT, including the SUVmax,SUVmean,SUVpeak, MTV and TLG are needed.

The relationship between tumor mean standard uptake value (SUVmax) in preoperative PET/computed tomography and prognostic risk groups in endometrial cancer

OBJECTIVE

Our aim in this study was to determine the relationship between tumor mean standard uptake value (SUVmax) value in preoperative PET/computed tomography (CT) and prognostic risk groups in cases with endometrial cancer.

METHODS

A total of 368 patients operated on for endometrial cancer were evaluated in the study. The SUVmax value of endometrial primary tumor of the patients screened within 30 days of operation, was compared with prognostic parameters and risk groups. P value <0.05 was considered significant for all tests.

RESULTS

A statistically significant relationship was found between the mean SUVmax value and risk groups ( P  < 0.001), grade ( P  < 0.001), stage ( P  < 0.001), myometrial invasion of the tumor ( P  < 0.001), cervical involvement ( P  = 0.002), lymphovascular space invasion (LVSI) ( P  < 0.001), lymph node metastasis ( P  < 0.001), tumor size ( P  < 0.001), lymph node involvement in PET/CT ( P  < 0.001). There was no significant relationship found between the histologic type of tumor and the mean SUVmax value ( P  = 0.113). Cutoff SUVmax value for endometrial cancer tumor tissue, which will be used to determine the possible lymph node metastasis, was accepted as 19 as a result of the ROC analysis. The risk of lymph node metastasis was found 4.74 times (confidence interval, 2.510-8.977) higher in patients with SUVmax value above cutoff 19 ( P  < 0.001). Considering risk groups, it was observed that patients with mean SUVmax value above 19 were in intermediate-high and high risk group, 2.3 times more than those in low and intermediate risk group ( P  < 0.001). As a result of logistic regression analysis, in determining intermediate-high and high-risk groups, histological type ( P  < 0.001), myometrial invasion ( P  = 0.003), cervical invasion (CI) ( P  < 0.001), grade ( P  = 0.018) and SUVmax value ( P  = 0.028) had statistically significant importance.

CONCLUSION

The higher the mean SUVmax value in the endometrial cancer tumor tissue in preoperative PET/CT in patients with endometrial cancer, the higher the risk group of the patients.

Hybrid PET/MRI in Staging Endometrial Cancer: Diagnostic and Predictive Value in a Prospective Cohort

AIM

The assessment of deep myometrial invasion (MI) and lymph node involvement is of utmost importance in the preoperative staging of endometrial cancer (EC). Imaging parameters derived respectively from MRI and PET have shown good predictive value. The main aim of the present study is to assess the diagnostic performance of hybrid 18F-FDG PET/MRI in EC staging, with particular focus on MI and lymphnodal involvement detection.

PATIENTS AND METHODS

Prospective monocentric study including 35 patients with biopsy-proven EC undergoing preoperative 18F-FDG PET/MRI (December 2018-March 2021) for staging purpose. Histological examination was the reference standard. PET (SUVmax, SUVmean with a threshold of 40% of SUVmax-SUVmean40, metabolic tumor volume, total lesion glycolysis) and MRI (volume index [VI], total tumor volume, tumor volume ratio [TVR], mean apparent diffusion coefficient, minimum apparent diffusion coefficient) parameters were calculated on the primary tumor, and their role in predicting EC risk group, the presence of lymphovascular space invasion (LVSI), and MI was assessed. Receiver operating characteristics analysis was used to assess the predictive value of PET and MRI parameters on EC characteristics.

RESULTS

Patients' median age was 66.57 years (SD, 10.21 years). 18F-FDG PET/MRI identified the primary tumor in all patients. Twenty-two of 35 patients had high-risk EC and 13/35 low-risk disease; 13/35 presented LVSI, 22/35 had deep MI at histological examination, and 13/35 had p53 hyperexpression.PET/MRI was able to detect lymphnodal involvement with high accuracy and high specificity (sensitivity of 0.8571, specificity of 0.9286, accuracy of 0.9143), also showing a high negative predictive value (NPV) for lymphnodal involvement (NPV of 0.9630, positive predictive value [PPV] of 0.7500).The assessment of deep MI using PET/MRI correctly staged 27 patients (77.1%; sensitivity of 0.7273, specificity of 0.8462, accuracy of 0.7714), with also a good PPV (PPV of 0.8889, NPV of 0.647).MRI-derived total tumor volume, VI, and TVR were significant in predicting EC groups (high-risk vs low-risk patients) (P = 0.0059, 0.0235, 0.0181, respectively). MRI-derived volume, VI, TVR, and PET-derived metabolic tumor volume and total lesion glycolysis were able to predict LVSI (P = 0.0023, 0.0068, 0.0068, 0.0027, 0.01394, respectively). Imaging was not able to predict grading, presence of deep MI, nor hyperexpression of p53.

CONCLUSIONS

18F-FDG PET/MRI has good accuracy in preoperative staging of EC; PET and MRI parameters have synergic role in preoperatively predicting LVSI, with MRI parameters being also predictive for EC risk group.

Association of Myometrial Invasion With Lymphovascular Space Invasion, Lymph Node Metastasis, Recurrence, and Overall Survival in Endometrial Cancer: A Meta-Analysis of 79 Studies With 68,870 Patients

Background

Myometrial invasion has been demonstrated to correlate to clinicopathological characteristics and prognosis in endometrial cancer. However, not all the studies have the consistent results and no meta-analysis has investigated the association of myometrial invasion with lymphovascular space invasion (LVSI), lymph node metastasis (LNM), recurrence, and overall survival (OS). Therefore, a meta-analysis was performed to evaluate the relationship between myometrial invasion and clinicopathological characteristics or overall survival in endometrial cancer.

Materials and Methods

A search of Pubmed, Embase, and Web of Science was carried out to collect relevant studies from their inception until June 30, 2021. The quality of each included study was evaluated using Newcastle–Ottawa scale (NOS) scale. Review Manager version 5.4 was employed to conduct the meta-analysis.

Results

A total of 79 articles with 68,870 endometrial cancer patients were eligible including 9 articles for LVSI, 29 articles for LNM, 8 for recurrence, and 37 for OS in this meta-analysis. Myometrial invasion was associated with LVSI (RR 3.07; 95% CI 2.17–4.35; p < 0.00001), lymph node metastasis (LNM) (RR 4.45; 95% CI 3.29–6.01; p < 0.00001), and recurrence (RR 2.06; 95% CI 1.58–2.69; p < 0.00001). Deep myometrial invasion was also significantly related with poor OS via meta-synthesis of HRs in both univariate survival (HR 3.36, 95% CI 2.35–4.79, p < 0.00001) and multivariate survival (HR 2.00, 95% CI 1.59–2.53, p < 0.00001). Funnel plot suggested that there was no significant publication bias in this study.

Conclusion

Deep myometrial invasion correlated to positive LVSI, positive LNM, cancer recurrence, and poor OS for endometrial cancer patients, indicating that myometrial invasion was a useful evaluation criterion to associate with clinical outcomes and prognosis of endometrial cancer since depth of myometrial invasion can be assessed before surgery. The large scale and comprehensive meta-analysis suggested that we should pay more attention to myometrial invasion in clinical practice, and its underlying mechanism also deserves further investigation.

Prognostic Value of Preoperative Imaging: Comparing 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography to Computed Tomography Alone for Preoperative Planning in High-risk Histology Endometrial Carcinoma

OBJECTIVE

18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) increases the sensitivity for preoperative detection of lymph nodes and distant metastases in endometrial cancer. The objective of this investigation was to determine the prognostic value of preoperative PET-CT compared with computed tomography (CT) alone for high-risk endometrial carcinoma.

MATERIALS AND METHODS

We performed a retrospective review of high-risk histology endometrial cancer from 2008 to 2015. Clinical variables including surgical procedure, preoperative imaging modality, and outcome were collected. Survival analysis was performed utilizing the Kaplan-Meier and Cox proportional hazards methodologies.

RESULTS

Of the 555 women treated for high-risk histology endometrial cancer, 88 (16%) had preoperative PET-CT, and 97 (17%) CT without PET available. PET-CT demonstrated positive findings in 37 women (42%) compared with 33 (30%) with preoperative CT alone. PET-CT had a positive predictive value of 96% for nodal metastasis compared with 60% for CT alone. The median follow-up time for the entire cohort was 59 months (range, 12 to 96 mo). Patients with a negative preoperative PET-CT (n=54) had a median progression-free survival (PFS) that was not reached, whereas the median PFS in the PET-CT positive group was 13 months (n=34). Women with a negative PET-CT had a longer median overall survival (OS) not yet reached compared with 34 months in the PET-CT positive cohort (hazard ratio, 2.4; P<0.001). CT findings did not associate with PFS or OS.

CONCLUSIONS

PET-CT demonstrated superior sensitivity for lymph node metastasis and detecting distant disease compared with CT. Preoperative PET-CT, whether positive or negative, offered OS and PFS prognostic value not observed with CT alone.

Prognostic value of metabolic tumor volume and total lesion glycolysis from ¹⁸F-FDG PET/CT in lymph node metastases and risk stratification of endometrial carcinoma

Objective

To investigate the prognostic value of metabolic tumor volume (MTV) and total lesion glycolysis (TLG), measured by preoperative ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT), in risk stratification of patients with endometrial carcinoma (EC).

Methods

The patients with pathological diagnosis of EC who underwent preoperative ¹⁸F-FDG PET/CT imaging were retrospectively selected for analysis of the prognostic values of PET parameters in risk classification and lymph node metastases (LNMs). Receiver-operating-characteristic analysis was used to analyze the correlation of PET parameters cutoff values with deep myometrial invasion (MI), lymphovascular space involvement and LNM for prognostic values in risk stratification.

Results

The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for detection of LNM are 83.3%, 99.7%, 90.9%, 99.5% and 99.2%, respectively. The MTV and TLG of primary lesion of EC in the patients with LNM are notably higher than those in patients without LNM, p<0.010. The MTV and TLG of the EC primary lesions in high-risk patients are significantly higher than those in low-risk patients (p<0.010), but the maximum standardized uptake value (SUVmax) is not. The MTV and TLG of primary lesions were superior to SUVmax for predicting of deep MI, LNM and high-risk of EC (p<0.005).

Conclusion

MTV and TLG of primary lesions are more valuable in predicting risk stratification of EC patients. Preoperative ¹⁸F-FDG PET/CT imaging is useful in predicting the LNM of EC and may help guide pelvic lymphadenectomy to avoid unnecessary pelvic lymphadenectomy in EC patients with low-risk stratification.

Preoperative evaluation of residual tumor in patients with endometrial carcinoma by using 18F-FDG PET/CT

Purpose: To evaluate the value of ¹⁸F-FDG positron emission tomography (PET)/computed tomography (CT) for determining the presence of residual tumors after curettage in patients with endometrial cancer. Methods: Preoperative ¹⁸F-FDG PET/CT was performed in 90 women with endometrial cancer. PET/CT parameters and clinical characteristics were compared between patients with and without residual tumors. The clinical characteristics of patients with residual tumors that showed low ¹⁸F-FDG uptake were also analyzed. Results: Among the 90 patients, 86 had residual tumors. ROC analysis identified a lesion SUVmax value of 5.0 as the optimal cut-off value for predicting whether or not patients had a residual tumor. With the SUVmax cut-off of 5, the sensitivity, specificity, positive predictive value, and negative predictive values for residual tumor prediction were 87.2%, 100%, 100%, and 26.7%, respectively. Univariate analysis showed significant associations between the high PET group (SUVmax > 5) and low PET group (SUVmax ≤ 5), and histologic type (P = 0.043) and tumor size (P < 0.001) in patients with residual tumors. In patients with low-grade and clear cell carcinomas and a tumor size < 1.35 cm, the probability of being in the low-PET group was 47.6%. In such patients, major parts of the residual tumors showed low ¹⁸F-FDG uptake, similar to that in patients with no residual tumors. Conclusion: SUVmax was the lone predictive value for the presence of residual tumors after curettage in patients with endometrial cancer. Lesion SUVmax greater than 5 suggested a high possibility of residual tumors. In patients with low-grade and clear cell carcinomas with tumor size < 1.35 cm, residual tumors may present low ¹⁸F-FDG uptake, mimicking the metabolic phenotypes of patients without residual tumors.

Prognostic value of metabolic tumor volume and total lesion glycolysis assessed by 18F-FDG PET/CT in endometrial cancer

OBJECTIVE

Surgical staging is the most confidential method for prognosis prediction. However, in which stage the surgery is needed and the treatment management of these patients is controversial. Presentation of new determinant factors with imaging methods for prediction of poor prognosis can provide better disease management. The aim of our study was to demonstrate the ability of metabolic tumor volume and total lesion glycolysis as a prognostic factor to predict the disease-free survival time, necessity of adjuvant radiotherapy-chemotherapy, and the association of these parameters with the clinicopathological features.

METHODS

Forty-four endometrial cancer diagnosed patients whose PET/CT scans were performed for treatment planning were included in our study. Metabolic parameters (SUVmax, metabolic tumor volume, total lesion glycolysis) of the primary tumor were calculated. Abdominal hysterectomy was performed for all patients. Histopathologic findings were noted. Patients were followed for 31.4 ± 14.8 months.

RESULTS

Metabolic tumor volume and total lesion glycolysis were significant prognostic factors for disease-free survival, whereas SUVmax did not effect disease-free survival. According to regression analysis, only metabolic tumor volume was found significant for radiotherapy planning (cutoff metabolic tumor volume; 26.30 ml). There was significant association between metabolic tumor volume, total lesion glycolysis and early-stage, myometrial invasion, and lymph node positivity. We observed only weak association between SUVmax and myometrial invasion. ROC curve calculated metabolic tumor volume and total lesion glycolysis cutoff values as 19.6 ml and 90 g for early-stage, 14.3 ml and 173.4 g for myometrial invasion, and 29.7 ml and 283.1 g for lymph node positivity, respectively.

CONCLUSION

Metabolic tumor volume and total lesion glycolysis may be used as prognostic factors for endometrial cancer. The association between SUVmax and clinical findings, disease-free survival, histopathological features are weak. Further studies are needed for demonstrating the prognostic value of metabolic volumetric parameters.

Integrating radiomics into holomics for personalised oncology: from algorithms to bedside

Radiomics, artificial intelligence, and deep learning figure amongst recent buzzwords in current medical imaging research and technological development. Analysis of medical big data in assessment and follow-up of personalised treatments has also become a major research topic in the area of precision medicine. In this review, current research trends in radiomics are analysed, from handcrafted radiomics feature extraction and statistical analysis to deep learning. Radiomics algorithms now include genomics and immunomics data to improve patient stratification and prediction of treatment response. Several applications have already shown conclusive results demonstrating the potential of including other “omics” data to existing imaging features. We also discuss further challenges of data harmonisation and management infrastructure to shed a light on the much-needed integration of radiomics and all other “omics” into clinical workflows. In particular, we point to the emerging paradigm shift in the implementation of big data infrastructures to facilitate databanks growth, data extraction and the development of expert software tools. Secured access, sharing, and integration of all health data, called “holomics”, will accelerate the revolution of personalised medicine and oncology as well as expand the role of imaging specialists.

Prognostic molecular biomarkers in endometrial cancer: A review

Background:

Endometrial cancer (EC) is the fourth most common malignancy in women worldwide and the most common gynecological cancer in developed countries. The endometrioid subtype has an excellent prognosis with conventional treatment; however, recurrence reduces overall survival.

Objective:

Describe the most relevant evidence regarding selected potential molecular biomarkers that may predict overall survival (OS), relapse-free survival (RFS), and cancer-specific survival (CSS) in EC.

Methods:

An exhaustive search was performed in PUBMED with the search terms endometrial cancer, molecular biomarker, and survival. We selected original articles written in English about endometrial cancer, molecular biomarkers, and that included survival analysis published between January 2000 and December 2016.

Results:

Several molecular prognostic biomarkers have been studied in terms of survival and therapeutic response in women with endometrial cancer; hormone receptors, microRNAs, and other molecules have emerged as potentially useful biomarkers, including HER2, p21, HE4, PTEN, p27, ANCCA, and ANXA2.

Conclusions:

The use of biomarkers in the assessment of OS, RFS, and CSS requires large trials to expand our understanding of endometrial carcinogenesis. Several molecular markers are significantly associated with a high tumor grade and advanced clinical stage in EC and, therefore, could have additive effects when combined.

Prognostic role of FDG PET-derived parameters in preoperative staging of endometrial cancer

PURPOSE

To investigate the preoperative prognostic role of ¹⁸F-FDG PET/CT in patients with endometrial carcinoma (EC).

METHODS

¹⁸F-FDG PET/CT was performed in 57 patients for EC preoperative staging. Maximum and mean standardized uptake values (SUVmax, mean), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of primary tumors, at different thresholds of 40%, 50%, 60% (40-50-60), were evaluated and compared with anatomopathological features. The diagnostic performance of PET-parameters (categorized by ROC analysis) in discriminating low-intermediate and high-risk disease and the prognostic role on survival (overall survival -OS; disease free survival - DFS) was evaluated.

RESULTS

The categorized TLG40-50-60 were the only parameters related to FIGO stage I versus II-III-IV (p = 0.0035 for all). The cut-off values for risk stratification were 83.69, 61.81 and 41.32, respectively (sensitivity: 60.00%; specificity; 71.43% for all parameters). Pathological stage 1 (pT1) of the primary tumor was predicted by MTV60 and TLG40-50 (p = 0.0328, 0.0240, 0.0147, respectively). The optimal thresholds were 7.795, 99.55 and 77.58, respectively (sensitivity: 38.46%, 53.85% and 53.85%, respectively; specificity: 88.64%, 79.55% and 81.82%, respectively). SUVmax and SUVmean40-50-60 were the only parameters discriminating endometrioid from non-endometrioid subtype. The corresponding sensitivity was 64.86% and 62.16% for SUVmax and SUVmean 50-60 and 62.16% for SUVmean40; specificity was 70.00% for all parameters. The mean (SD) OS was 79.77% (3.34%) and the mean DFS was 77.89% (3.73%). The tumor type was the only variable significantly associated with OS (p = 0.0486). TLG50 > 77.58 cm³ was the only variable associated with a higher risk of relapse (p = 0.0472).

CONCLUSION

TLG40-50-60 and MTV60 of primary EC have prognostic value in discriminating FIGO and pathological staging. These results suggest a possible role of these parameters in predicting EC aggressiveness, thus improving the preoperative characterization of endometrial cancer.

Clinical and prognostic value of 18F-FDG PET/CT in recurrent endometrial carcinoma

PURPOSE

Endometrial carcinoma (EC) is a cancer with a good overall prognosis, except in cases of recurrent or advanced EC. The aim of this study was to assess the diagnostic performance, the prognostic value and the impact on therapeutic management of ¹⁸F-FDG PET/CT in suspected recurrent EC.

MATERIALS AND METHODS

We retrospectively evaluated 157 patients with histologically proven EC and restaging ¹⁸F-FDG PET/CT for suspected recurrence. The PET images were analyzed visually and semi-quantitatively by measuring SUVmax, MTV and TLG. A combination of clinical/imaging follow-up and/or histopathology was taken as reference standard. Progression-free survival (PFS) and overall survival (OS) were computed using Kaplan-Meier curves.

RESULTS

Seventy-nine patients had positive ¹⁸F-FDG PET/CT showing the presence of at least one hypermetabolic lesion consistent with recurrence, while the remaining 78 were negative. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of ¹⁸F-FDG PET/CT were 96%, 99%, 99%, 96%, 97%, respectively, and were higher compared to conventional imaging: 97%, 62%, 72%, 96%, 80%. After a mean follow-up of 39months, relapse/progression occurred in 58 patients and death in 37 with an average time of 22.1 and 27.6months, respectively. A positive ¹⁸F-FDG PET/CT and advanced FIGO stage were significantly associated with shorter PFS and OS. PET/CT results had a significant impact on therapeutic approach in 33 patients: avoiding unnecessary therapies in 28 and modifying therapy in 5.

CONCLUSIONS

¹⁸F-FDG PET/CT has a very good diagnostic performance in patients with suspected recurrent EC and has an important prognostic value in assessing PFS and OS. Moreover, PET/CT allowed for a change in treatment decision in about 20% of cases.

Radiomics of the primary tumour as a tool to improve 18F-FDG-PET sensitivity in detecting nodal metastases in endometrial cancer

Background

A radiomic approach was applied in 18F-FDG PET endometrial cancer, to investigate if imaging features computed on the primary tumour could improve sensitivity in nodal metastases detection. One hundred fifteen women with histologically proven endometrial cancer who underwent preoperative 18F-FDG PET/CT were retrospectively considered. SUV, MTV, TLG, geometrical shape, histograms and texture features were computed inside tumour contours. On a first group of 86 patients (DB1), univariate association with LN metastases was computed by Mann-Whitney test and a neural network multivariate model was developed. Univariate and multivariate models were assessed with leave one out on 20 training sessions and on a second group of 29 patients (DB2). A unified framework combining LN metastases visual detection results and radiomic analysis was also assessed.

Results

Sensitivity and specificity of LN visual detection were 50% and 99% on DB1 and 33% and 95% on DB2, respectively. A unique heterogeneity feature computed on the primary tumour (the zone percentage of the grey level size zone matrix, GLSZM ZP) was able to predict LN metastases better than any other feature or multivariate model (sensitivity and specificity of 75% and 81% on DB1 and of 89% and 80% on DB2). Tumours with LN metastases are in fact generally characterized by a lower GLSZM ZP value, i.e. by the co-presence of high-uptake and low-uptake areas. The combination of visual detection and GLSZM ZP values in a unified framework obtained sensitivity and specificity of 94% and 67% on DB1 and of 89% and 75% on DB2, respectively.

Conclusions

The computation of imaging features on the primary tumour increases nodal staging detection sensitivity in 18F-FDG PET and can be considered for a better patient stratification for treatment selection. Results need a confirmation on larger cohort studies.

Prognostic value of metabolic parameters determined by preoperative ¹⁸F-FDG PET/CT in patients with uterine carcinosarcoma

Objective

To evaluate the prognostic value of metabolic parameters measured by preoperative ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) in patients with uterine carcinosarcoma (UCS).

Methods

Data of 55 eligible patients with UCS who underwent preoperative ¹⁸F-FDG PET/CT and surgical staging were analyzed retrospectively. Maximum standardized uptake value (SUV_max), metabolic tumor volume (MTV_2.5), and total lesion glycolysis (TLG_2.5) of the primary tumors were measured using a SUV threshold of 2.5. The optimal cutoff value of each parameter was determined by time-dependent receiver operating characteristic curve, and its impact on progression-free survival and overall survival was evaluated by Cox proportional hazards model.

Results

During a median follow-up period of 29 (range, 1.5–109.4) months, 47.3% (26/55) of the patients experienced disease progression, and the disease-associated mortality rate was 43.6% (24/55). Univariate analysis determined that hazard ratios (HRs) for disease progression for SUV_max (≥8.33), MTV_2.5 (≥63.92 mL), and TLG_2.5 (≥396.16) were 1.930 (95% confidence interval [CI]=0.793–4.701), 3.264 (95% CI=1.466–7.268), and 2.692 (95% CI=1.224–5.924), respectively. And, HRs for death were 1.979 (95% CI=0.774–5.060), 2.764 (95% CI=1.217–6.274), and 2.721 (95% CI=1.198–6.182), respectively. While peritoneal cytology, histology, and tumor diameter were independent prognostic factors in multivariate analysis, MTV and TLG were not.

Conclusion

Though MTV and TLG of primary UCS were not independent predictors compared to surgically obtained data, MTV and TLG of primary UCS may provide useful information on prognosis especially in patients who are not able to undergo surgical staging.

Different imaging techniques for the detection of pelvic lymph nodes metastasis from gynecological malignancies: a systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate the diagnostic performance of different imaging techniques and the corresponding diagnostic criteria for preoperative detection of pelvic lymph node metastasis from gynecological carcinomas.

METHODS

Six databases were systematically searched for retrieving eligible studies. Study inclusion, data extraction and risk of bias assessment were performed by 2 reviewers independently. STATA 14.0 was used to perform the meta-analysis.

RESULTS

Eighty eligible studies were collected. The pooled sensitivity, specificity, and area under curve (AUC) of CT, MRI and DWI were 47%, 93%, 0.7424; 50%, 95%, 0.8039 and 84%, 95%, 0.9523 respectively. As regards PET, PET-CT and US, the pooled sensitivity, specificity and AUC were 56%, 97%, 0.9592; 68%, 97%, 0.9363 and 71%, 99%, 0.9008 respectively. The summary receiver operating characteristic (SROC) curve indicated that the systematic diagnostic performances of PET, PET-CT, DWI were superior to other imaging modalities.

CONCLUSIONS

The present work demonstrated that DWI, PET, PET-CT were the top-priority consideration of imaging modalities for detecting metastatic pelvic lymph node in gynecological carcinoma. DWI was recommended as the first choice for metastasis exclusion and all the other imaging techniques including CT and MRI were suitable for metastasis conformation. However, for the early stage lymph node malignancy, PET or PET-CT could represent a better choice. More studies exploring the diagnostic efficacy of detailed criteria are required in the future.

Recurrent patterns of DNA copy number alterations in tumors reflect metabolic selection pressures

Copy number alteration (CNA) profiling of human tumors has revealed recurrent patterns of DNA amplifications and deletions across diverse cancer types. These patterns are suggestive of conserved selection pressures during tumor evolution but cannot be fully explained by known oncogenes and tumor suppressor genes. Using a pan-cancer analysis of CNA data from patient tumors and experimental systems, here we show that principal component analysis-defined CNA signatures are predictive of glycolytic phenotypes, including 18F-fluorodeoxy-glucose (FDG) avidity of patient tumors, and increased proliferation. The primary CNA signature is enriched for p53 mutations and is associated with glycolysis through coordinate amplification of glycolytic genes and other cancer-linked metabolic enzymes. A pan-cancer and cross-species comparison of CNAs highlighted 26 consistently altered DNA regions, containing 11 enzymes in the glycolysis pathway in addition to known cancer-driving genes. Furthermore, exogenous expression of hexokinase and enolase enzymes in an experimental immortalization system altered the subsequent copy number status of the corresponding endogenous loci, supporting the hypothesis that these metabolic genes act as drivers within the conserved CNA amplification regions. Taken together, these results demonstrate that metabolic stress acts as a selective pressure underlying the recurrent CNAs observed in human tumors, and further cast genomic instability as an enabling event in tumorigenesis and metabolic evolution.

What Is the Best Preoperative Imaging for Endometrial Cancer?

Although endometrial cancer is surgicopathologically staged, preoperative imaging is recommended for diagnostic work-up to tailor surgery and adjuvant treatment. For preoperative staging, imaging by transvaginal ultrasound (TVU) and/or magnetic resonance imaging (MRI) is valuable to assess local tumor extent, and positron emission tomography-CT (PET-CT) and/or computed tomography (CT) to assess lymph node metastases and distant spread. Preoperative imaging may identify deep myometrial invasion, cervical stromal involvement, pelvic and/or paraaortic lymph node metastases, and distant spread, however, with reported limitations in accuracies and reproducibility. Novel structural and functional imaging techniques offer visualization of microstructural and functional tumor characteristics, reportedly linked to clinical phenotype, thus with a potential for improving risk stratification. In this review, we summarize the reported staging performances of conventional and novel preoperative imaging methods and provide an overview of promising novel imaging methods relevant for endometrial cancer care.

Prognostic impact of primary tumor SUVmax on preoperative 18F-fluoro-2-deoxy-D-glucose positron emission tomography and computed tomography in endometrial cancer and uterine carcinosarcoma

The objective of the present study was to investigate the usefulness of the maximum standardized uptake value (SUV_max) of the primary tumor on preoperative ¹⁸F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography and computed tomography (PET/CT) as a prognostic indicator in patients with endometrial neoplasms. A total of 75 patients with endometrial cancer or uterine carcinosarcoma who underwent surgical treatment were included in the present study. All patients underwent preoperative PET/CT, and the correlation between the SUV_max of the primary tumor and clinical outcomes was analyzed. The SUV_max was significantly higher in patients with stage II/III disease, a histology of grade 3 endometrioid adenocarcinoma and carcinosarcoma, a positive lymph node (LN) status, positive lymph-vascular space involvement (LVSI), and deep (≥1/2) myometrial invasion. Receiver operating characteristic curve analysis revealed that the optimal cut-off values of SUV_max for predicting a positive LN, LVSI and deep myometrial invasion were 7.49, 6.45 and 6.45, respectively. The overall survival (OS) and progression-free survival (PFS) of patients with a high SUV_max were significantly lower compared with those of patients with a low SUV_max using the cut-off value of 7.30. However, no significant difference was observed in the OS or PFS between the high and low SUV_max groups when analyzed in carcinosarcoma patients alone. Finally, multivariate analyses demonstrated that the SUV_max of the primary tumor was an independent prognostic factor for impaired PFS in 55 endometrioid adenocarcinoma patients; however, not in all patients, including those with carcinosarcoma. The present findings demonstrated that the SUV_max of the primary tumor may be a useful biomarker for predicting clinical outcomes of patients with endometrial cancer, although its prognostic impact appears to be limited in patients with uterine carcinosarcoma.

Role of PET-CT Scan in Gynaeconcology

THE PURPOSE OF THIS STUDY

This study was undertaken to evaluate the role of positron emission tomography-CT (PET-CT) in diagnosis and management of gynecological malignancies in primary and recurrent settings and also to investigate its role in inappropriately treated patients, for pretreatment evaluation (staging) to help in proper therapeutic management.

METHOD

This is a retrospective study of 56 patients of gynecological malignancy registered in Gujarat Cancer Research Institute from June 2011 to December 2013.

RESULTS

Out of 56 cases where PET was done, the results were as follows: carcinoma cervix-23, carcinoma ovary-20, carcinoma endometrium-9, carcinoma vulva-1, carcinoma vagina-2, and GTN-1. PET scan was negative in 37 % of patients where CT scan was suspicious, which changed the therapeutic modality and prevented further unnecessary interventions. In cases where clinical suspicion of recurrence was high based on rising tumor marker and CT scan was negative, subsequent PET-CT was able to pick up malignancy in 75 % cases. Eleven patients (25 %) with suspected recurrence with inconclusive CT scan and negative PET-CT scan were kept on follow-up, thus reducing further morbidity and cost.

CONCLUSION

Addition of PET-CT, a noninvasive method to the oncologist's imaging armamentarium may ultimately improve both outcomes and costs by altering management strategies in primary and recurrent settings. The potential use of PET-CT appears promising in several decision-making steps in the management of patients with gynecological malignancy. It defines the extent of metastatic disease which enables the clinician to decide regarding salvageable surgical intervention or palliative measures.

Primary tumor SUVmax on preoperative FDG-PET/CT is a prognostic indicator in stage IA2-IIB cervical cancer patients treated with radical hysterectomy

The objective of the present study was to investigate the prognostic value of ¹⁸F-fluoro-2-deoxy-D-glucose (FDG) uptake by primary tumors on positron emission tomography/computed tomography (PET/CT) in surgically resectable cervical cancer. A total of 59 patients with stage IA2-IIB cervical cancer who underwent preoperative FDG-PET/CT, followed by radical hysterectomy and lymphadenectomy, were included in the study. The maximum standardized uptake value (SUV_max) of the primary tumor was measured, and the association between the SUV_max and clinicopathological factors or patient outcomes was analyzed. The SUV_max was significantly higher in patients with an advanced stage, lymph node metastasis, lymph-vascular space involvement and large tumors. The overall survival (OS) and progression-free survival (PFS) of patients with a high SUV_max were significantly lower compared with patients with a low SUV_max, using an optimal cut-off value of 7.36 for OS and 5.59 for PFS obtained from receiver operating characteristic curve analysis. Similarly, OS and PFS in patients with a high SUV_max were significantly lower in 39 patients with stage IB using a cut-off value of 7.90 and 6.69 for OS and PFS, respectively. Finally, multivariate analyses showed that the SUV_max of the primary tumor was an independent prognostic factor for impaired PFS in all patients and those with stage IB alone. These findings demonstrated that a high SUV_max on preoperative PET/CT was correlated with unfavorable clinical outcomes in patients receiving radical hysterectomy, suggesting that the SUV_max of the primary tumor may be a prognostic indicator for surgically-treated, early-stage invasive cervical cancer.

High Diagnostic Value of 18F-FDG PET/CT in Endometrial Cancer: Systematic Review and Meta-Analysis of the Literature

The aim of this study was to evaluate the diagnostic performance of (18)F-FDG PET/CT for the preoperative assessment of lymph node metastases (LNM) in endometrial cancer patients and for the assessment of endometrial cancer recurrence (ECR) after primary surgical treatment.

METHODS

A comprehensive search was performed on Pubmed/MEDLINE databases for studies reporting the diagnostic performance of (18)F-FDG PET/CT for assessment of LNM and ECR published up to August 15, 2015. Twenty-one studies (13 for LNM and 8 for ECR) were included in the systematic review and meta-analysis. Pooled estimates of sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of the (18)F-FDG PET/CT were calculated along with 95% confidence intervals (CIs). A summary receiver-operating-characteristics curve (SROC) was constructed, and the area under the SROC curve (AUC) was determined along with Q* index.

RESULTS

The overall pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and AUC (with 95% CI) of (18)F-FDG PET/CT for detection of LNM were 0.72 (95% CI, 0.63-0.80), 0.94 (95% CI, 0.93-0.96), 10.9 (95% CI, 7.9-15.1), 0.36 (95% CI, 0.27-0.48), 39.7 (95% CI, 21.4-73.6), and 0.94 (95% CI, 0.85-0.99), respectively, whereas the corresponding numbers for detection of ECR were 0.95 (95% CI, 0.91-0.98), 0.91 (95% CI, 0.86-0.94), 8.8 (95% CI, 6.0-12.7), 0.08 (95% CI, 0.05-0.15), 171.7 (95% CI, 67.9-434.3), and 0.97 (95% CI, 0.95-0.98), respectively. The overall diagnostic accuracy (Q* index) in LNM and ECR were 0.88 and 0.93, respectively.

CONCLUSION

(18)F-FDG PET/CT has an excellent diagnostic performance for detecting LNM preoperatively and disease recurrence postoperatively in endometrial cancer patients.

Standardized Uptake Value on F-FDG PET/CT as a Prognostic Factor for Survival of Women with Malignant Uterine Tumors: A Meta-Analysis

BACKGROUND

Malignant uterine tumors are crucial in the evaluation of prognosis and the determination of therapeutic strategy.

AIM

This meta-analysis of the available literature aimed to investigate the prognostic value of standardized uptake value (SUV) on fluorine-18-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG PET/CT) in uterine malignancies before treatment.

METHODS

The PubMed, MEDLINE and EMBASE databases (1990 to February 2014) were searched to identify studies evaluating SUV on 18F-FDG PET/CT as a prognostic tool for predicting long-term survival in patients with carcinomas of the uterus. The χ2 test and the I2 index were used to estimate heterogeneity among the trials selected in the meta-analysis. The combined hazard ratio was calculated by using a fixed- or random-effects model according to heterogeneity.

RESULTS

Thirteen studies with a total of 1,196 patients were eligible for analysis. High pretreatment SUVmax was significantly associated with poorer event-free survival and overall survival, and the summarized hazard ratio was 3.33 (95% confidence interval 2.34-4.74) and 1.31 (95% confidence interval 1.03-1.67), respectively.

CONCLUSION

The present evidence indicates that SUV on 18F-FDG PET/CT seems to be a valuable prognostic indicator for survival of patients with malignant uterine tumors. Given that 18F-FDG PET/CT can provide both morphologic and functional information, we suggest utilizing PET/CT and its quantitative marker in uterine malignancies before treatment. © 2015 S. Karger AG, Basel.

Maximum standardized uptake value of fluorodeoxyglucose positron emission tomography/computed tomography is a prognostic factor in ovarian clear cell adenocarcinoma

BACKGROUND

Fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is useful for diagnosing malignant tumors. Intracellular FDG uptake is measured as the standardized uptake value (SUV), which differs depending on tumor characteristics. This study investigated differences in maximum SUV (SUVmax) according to histologic type in ovarian epithelial cancer and the relationship of SUVmax with prognosis.

METHODS

This study included 80 patients with ovarian epithelial cancer based on histopathologic findings at surgery and who had undergone PET/CT before treatment. Maximum SUV on PET/CT of primary lesions and histopathology were compared based on histologic type, and the prognosis associated with different SUVmax was evaluated.

RESULTS

Clinical tumor stage was I in 35 patients, II in 8, III in 25, and IV in 12. Histologic type was serous adenocarcinoma (AC) in 33 patients, clear cell AC in 27, endometrioid AC in 15, and mucinous AC in 5. Median SUVmax was lower in mucinous AC (2.76) and clear cell AC (4.9) than in serous AC (11.4) or endometrioid AC (11.4). Overall, median SUVmax was lower in clinical stage I (5.37) than in clinical stage ≥II (10.3). However, in both clear cell AC and endometrioid AC, when histologic evaluation was possible, no difference was seen between stage I and stage ≥II. Moreover, in clear cell AC, the 5-year survival rate was significantly higher in the low-SUVmax group (100%) than in the high-SUVmax group (43.0%, P = 0.009).

CONCLUSIONS

Maximum SUV on preoperative FDG-PET/CT in ovarian epithelial cancer differs according to histologic type. In clear cell AC, SUVmax may represent a prognostic factor.

Standardized uptake value and apparent diffusion coefficient of endometrial cancer evaluated with integrated whole-body PET/MR: Correlation with pathological prognostic factors

PURPOSE

To evaluate the correlation between maximum standardized uptake value (SUVmax ) and minimum apparent diffusion coefficient (ADCmin ) of endometrial cancer derived from an integrated positron emission tomography / magnetic resonance (PET/MR) system and to determine their correlation with pathological prognostic factors.

MATERIALS AND METHODS

This prospective study was approved by the Institutional Review Board of the hospital, and informed consent was obtained. Between April and December 2014, 47 consecutive patients with endometrial cancer were enrolled and underwent simultaneous PET/MR examinations before surgery. Thirty-six patients with measurable tumors on PET/MR were included for image analysis. Pearson's correlation coefficient was used to evaluate the correlation between SUVmax and ADCmin of the tumors. The Mann-Whitney U-test was utilized to evaluate relationships between these two imaging biomarkers and pathological prognostic factors.

RESULTS

The mean SUVmax and ADCmin were 14.7 ± 7.1 and 0.48 ± 0.13 × 10(-3) mm(2) /s, respectively. A significant inverse correlation was found between SUVmax and ADCmin (r = -0.53; P = 0.001). SUVmax was significantly higher in tumors with advanced stage, deep myometrial invasion, cervical invasion, lymphovascular space involvement, and lymph node metastasis (P < 0.05). ADCmin was lower in tumors with higher grade, advanced stage, and cervical invasion (P < 0.05). The ratio of SUVmax to ADCmin was higher in tumors with higher grade, advanced stage, deep myometrial invasion, cervical invasion, lymphovascular space involvement, and lymph node metastasis (P < 0.05).

CONCLUSION

SUVmax and ADCmin of endometrial cancer derived from integrated PET/MR are inversely correlated and are associated with pathological prognostic factors.

Preoperative risk stratification using metabolic parameters of (18)F-FDG PET/CT in patients with endometrial cancer

PURPOSE

To evaluate the usefulness of metabolic parameters obtained by (18)F-FDG PET/CT for preoperative stratification of high-risk and low-risk endometrial carcinomas.

METHODS

Preoperative (18)F-FDG PET/CT was performed in 56 women with endometrial cancer. Maximum standardized uptake values (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) of primary tumours were compared with clinicopathological features of surgical specimens. Diagnostic performance in terms of differentiation of low-risk disease (endometrioid histology, histological grade 1 or 2, invasion of less than half of the myometrium, and FIGO stage I) from high-risk disease was assessed.

RESULTS

MTV and TLG were significantly higher in patients with higher histological grade (p = 0.0026 and p = 0.034), larger tumour size (p = 0.002 and p = 0.0017), lymphovascular space involvement (LVSI; p = 0.012 and p = 0.0051), myometrial invasion (p = 0.027 and p = 0.031), cervical stromal invasion (p = 0.023 and p = 0.014), ovarian metastasis (p = 0.00022 and p = 0.00034), lymph node metastasis (p < 0.0001 and p < 0.0001), and higher FIGO stage (p = 0.0011 and p = 0.00048). SUVmax was significantly higher in patients with larger tumour size (p = 0.0025), LVSI (p = 0.00023) and myometrial invasion (p < 0.0001). The areas under the ROC curves (AUCs) for distinguishing high-risk from low-risk carcinoma were 0.625, 0.829 and 0.797 for SUVmax, MTV and TLG, respectively. AUCs for both MTV and TLG were significantly larger than that for SUVmax (p = 0.0049 and p = 0.021). The optimal TLG cut-off value of 70.2, determined by ROC analysis, was found to have 72.0% sensitivity and 74.2% specificity for risk stratification.

CONCLUSION

MTV and TLG of primary endometrial cancer show better correlations with clinicopathological features and are more useful for differentiating high-risk from low-risk carcinoma than SUVmax.

Role of 18F-FDG PET/CT in the carcinoma of the uterus: a review of literature

In the present review we reported the value of 18F-fluorodeoxyglucose (FDG) PET/CT in face of uterine cancer, in terms of sensitivity, specificity and accuracy. Moreover, we made a comparison with the other imaging techniques currently used to evacuate these tumors including contrast-enhanced CT, contrast enhanced-MRI and transvaginal ultrasonography. FDG PET/CT has been reported to be of particular value in detecting occult metastatic lesions, in prediction of response to treatment and as a prognostic factor.

Preoperative PET/CT standardized FDG uptake values of pelvic lymph nodes as a significant prognostic factor in patients with endometrial cancer

PURPOSE

Using integrated PET/CT, we evaluated the prognostic relevance of preoperative pelvic lymph node (LN) (18)F-FDG uptake in endometrioid endometrial cancer.

METHODS

We retrospectively reviewed patients with pathologically proven endometrial cancer who underwent preoperative (18)F-FDG PET/CT scans to evaluate the prognostic significance of PET/CT parameters and other clinicopathological variables. We used Cox proportional hazards regression to examine the relationship between recurrence and the maximum standardized uptake value (SUVmax) in pelvic LNs (SUVLN) on FDG PET/CT.

RESULTS

Clinical data, treatment modalities and results were reviewed in 70 eligible patients. The median postsurgical follow-up was 29 months (range 6 to 95 months). Receiver-operating characteristic analysis identified the significant SUVLN cut-off value as 15. The SUVLN correlated with FIGO stage (P < 0.001), LN metastasis (P < 0.001), lymphovascular space invasion (P < 0.001), SUVtumour (P = 0.001), metastatic LN size (P = 0.004), primary tumour size (P = 0.012), tumour grade (P = 0.015) and depth of tumour invasion (P = 0.035). Regression analysis showed a statistically significant association between recurrence and SUVLN (P = 0.002). Recurrence differed significantly (P < 0.001) between patients with SUVLN >15 and those with SUVLN ≤15.

CONCLUSION

Preoperative pelvic LN FDG uptake exhibited a strong significant association with recurrence of endometrioid endometrial cancer.

Correlation between expression of biological markers and [F]fluorodeoxyglucose uptake in endometrial cancer

PURPOSE

Positron emission tomography/computer tomography (PET/CT) utilizing [(18)F]fluorodeoxyglucose ((18)F-FDG) has been recommended for the diagnosis, staging, therapy monitoring, prediction of prognosis, and detection of recurrence in endometrial cancer. We aimed to define the correlations of biological markers with (18)F-FDG uptake in endometrial cancer.

METHODS

29 patients (55 ± 8.93 years) with endometrial cancer were included in this study. All patients underwent hysterectomy and bilateral salpingo-oophorectomy with or without para-aortic lymphadenectomy at the department of Obstetrics and Gynecology of Pusan National University Hospital. Immunohistochemical studies were performed for glucose transporter 1 (GLUT-1), hexokinase II (HK-II), hypoxia-inducible factor 1α (HIF-1α), vascular endothelial growth factor (VEGF) and carbonic anhydrase IX (CA-IX).

RESULTS

There were positive correlations between FDG uptake and GLUT-1 (r = 0.375, p = 0.0452), and HK-II (r = 0.537, p = 0.0027). However, HIF-1α (r = 0.153, p = 0.4283), VEGF (r = -0,101, p = 0.6032) and CA-IX (r = 0.240, p = 0.2105) were not significantly associated with FDG uptake. No significant correlations were found among the expression levels of biological markers.

CONCLUSION

FDG uptake in endometrial cancer was significantly associated with GLUT-1 and HK-II, while HIF-1α, VEGF and CA-IX were not associated with FDG uptake. No significant correlations were found among the expression levels of biological markers.

The preoperative maximum standardized uptake value measured by 18F-FDG PET/CT as an independent prognostic factor of overall survival in endometrial cancer patients

PURPOSE

The aim of this study was to determine if the preoperative maximum standardized uptake value (SUVmax) measured by 18F-FDG PET/CT in the primary tumor has prognostic value in the group of patients with endometrial cancer.

PATIENTS, MATERIALS, AND METHODS

A total of one hundred one consecutive endometrial cancer patients, age range 40-82 years (mean 62 years) and FIGO I-IV stage, who underwent 18-FDG-PET/CT within two weeks prior radical surgery, were enrolled to the study. The maximum SUV was measured and compared with the clinicopathologic features of surgical specimens. The relationship between SUVmax and overall survival was analyzed.

RESULTS

The mean preoperative SUVmax was 14.34; range (3.90-33.80) and was significantly lower for FIGO I than for higher stages (P = 0.0012), as well as for grade 1 than for grade 2 and 3 (P = 0.018), deep myometrial invasion (P = 0.0016) and for high risk group (P = 0.0004). The analysis of survival ROC curve revealed SUVmax cut-off value of 17.7 to predict high risk of recurrence. Endometrial cancer patients with SUVmax higher than 17.7 characterized by lower overall survival.

CONCLUSION

The preoperative SUVmax measured by 18F-FDG PET/CT is considered as an important indicator reflecting tumor aggressiveness which may predict poor prognosis. High value of SUVmax would be useful for making noninvasive diagnoses and deciding the appropriate therapeutic strategy for patients with endometrial cancer.

Diagnostic Performance of Fluorine 18 Fluorodeoxyglucose Positron Emission Tomography Imaging for Detection of Primary Lesion and Staging of Endometrial Cancer Patients: Systematic Review and Meta-Analysis of the Literature

Objectives

Fluorine 18 fluorodeoxyglucose positron emission tomography (18F-FDG PET) imaging has been used for staging of endometrial cancer. In the current study, we systematically searched the available literature on the accuracy of 18F-FDG PET imaging for staging of endometrial cancer.

Methods

PubMed, SCOPUS, ISI Web of Knowledge, Science Direct, and Springer were searched using “endometr* AND PET” as the search terms. All studies evaluating the accuracy of 18F-FDG PET in the staging of endometrial carcinoma were included. Statistical pooling of diagnostic accuracy indices was done using random-effects model. Cochrane Q test and I2 index were used for heterogeneity evaluation.

Results

Sixteen studies (807 patients in total) were included in the meta-analysis. Sensitivity and specificity for detection of the primary lesions were 81.8% (77.9%–85.3%) and 89.8% (79.2%–96.2%); for lymph node staging were 72.3% (63.8%–79.8%) and 92.9% (90.6%–94.8%); and for distant metastasis detection were 95.7% (85.5%–99.5%) and 95.4% (92.7%–97.3%).

Conclusions

Because of low sensitivity, diagnostic utility of 18F-FDG PET imaging is limited in primary tumor detection and lymph node staging of endometrial cancer patients. However, high specificities ensure high positive predictive values in these 2 indications. Diagnostic performance of 18F-FDG PET imaging is much better in detection of distant metastases. Larger studies with better design are needed to draw any more definite conclusion.

Tailoring systematic lymphadenectomy in high-risk clinical early stage endometrial cancer: the role of 18F-FDG PET/CT

OBJECTIVES

To evaluate the role of FDG PET/CT in the preoperative N-staging of high-risk clinical stage I endometrial cancer. The correlation between the metabolic characteristics of endometrial tumor uptake as predictors of a) lymph-node (LN) metastases and b) recurrence, was also evaluated.

METHODS

Seventy-six high-risk (G2 with deep myometrial invasion, G3, serous/clear-cell carcinoma) clinical stage I endometrial cancer patients underwent preoperative PET/CT scan followed by total hysterectomy, bilateral salpingo-oophorectomy and lymphadenectomy. PET/CT images were analyzed and correlated to histological findings. Maximal and mean standardized uptake value (SUVmax, SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG, defined as the product between SUVmean and MTV) of endometrial lesions were calculated and correlated to: a) presence of LN metastases, b) recurrences.

RESULTS

PET/CT resulted positive at LNs in 12/76 patients: 11/12 truly positive, 1/12 falsely positive. Conversely PET/CT was negative in 64/76 patients: 61/64 truly negative and 3/64 falsely negative. On pt-based analysis, sensitivity, specificity, accuracy, positive and negative predictive value of PET/CT in detecting LN metastases were 78.6%, 98.4%, 94.7%, 91.7%, 95.3%, respectively. A significant association was found between the presence of LN metastases and SUVmax (p=0.038), MTV (p=0.007), TLG (p=0.003) of the primary tumor. No correlations were found between the metabolic parameters and relapse (median follow-up 25.4months).

CONCLUSIONS

In high-risk clinical stage I endometrial cancer FDG PET/CT demonstrated moderate sensitivity, high specificity and accuracy for the nodal status assessment. SUVmax, MTV and TLG of the primary tumor are significantly correlated to LN metastases, while none of these parameters is predictor of recurrence.