Controversies in surgical staging of endometrial cancer

Accuracy of MRI in predicting deep myometrial invasion in endometrial cancer and the influence of leiomyoma, adenomyosis and the microcystic elongated and fragmented tumour pattern

INTRODUCTION

The most common form of endometrial cancer is Type 1 endometrioid adenocarcinoma. Depth of myometrial invasion is the most important prognostic factor correlating with overall patient survival. The objective was to investigate how accurate magnetic resonance imaging (MRI) is in predicting the depth of myometrial invasion in preoperative assessment, and the influence of leiomyoma and/or adenomyosis, or microcystic, elongated and fragmented (MELF) pattern of invasion on MRI diagnostic performance.

METHOD

Retrospective audit of 235 endometrial cancer patients from the regional Gynaecology Oncology multidisciplinary meeting at Auckland City Hospital, between January 2020 and January 2021. Radiologist assigned stage was compared to histopathology. Presence of leiomyoma, adenomyosis and MELF pattern evaluated followed by analysis under a Biostatistician's supervision.

RESULTS

Overall MRI diagnostic accuracy for depth of myometrial invasion was 86%. For deep myometrial invasion, MRI had a sensitivity of 72% and specificity 91%. Out of the misreported 32/235 cases, 16 demonstrated fibroids and/or adenomyosis leading to a sensitivity of 57% and specificity 93% for deep invasion, compared with 94% and 74% respectively in the population without, demonstrating statistical significance. Thirty seven cases with MELF pattern of invasion showed a sensitivity of 81% and specificity 80% for deep invasion, compared with 63% and 92% respectively in the group without, demonstrating no statistical significance.

CONCLUSION

MRI assessment of the depth of myometrial invasion in endometrial cancer has high accuracy. In the presence of background uterine fibroids/adenomyosis, pre-operative MRI accuracy of evaluating deep invasion shows a statistically significant reduction.

A Review of Laparoscopic Para-aortic Lymphadenectomy for Early-stage Endometrial Cancer: Extraperitoneal Approach May Have the Advantage over Intraperitoneal Approach

The importance of lymphadenectomy, including para-aortic nodes, for the accurate staging of endometrial cancer, is well established. Although the therapeutic role of lymph node resection in endometrial cancer is still under debate, some studies support its usefulness for survival benefit. To predict the necessity of lymphadenectomy, several preoperative scoring systems have been proposed as being effective. For endometrial cancer, there is a trend towards minimally invasive surgery, including para-aortic lymphadenectomy. For para-aortic lymphadenectomy, there are two different approaches: the extraperitoneal approach and the transperitoneal approach. The extraperitoneal approach has advantages over the transperitoneal approach in terms of better access to the left aortic nodes, no interference of the bowel, and possibly better options for obese or elderly patients. However, the extraperitoneal approach may have a longer learning curve than the transperitoneal approach. Robot-assisted extraperitoneal para-aortic lymphadenectomy is feasible and safe and may be suitable for patients irrespective of their baseline characteristics.

Evaluation of the role of intraoperative frozen section and magnetic resonance imaging in endometrial cancer

OBJECTIVE

To evaluate the accuracy of preoperative endometrial biopsy and magnetic resonance imaging (MRI) of endometrial cancer compared with that of intraoperative frozen section.

METHODS

This retrospective study included 264 patients who underwent surgery with intraoperative frozen section for endometrial cancer at our institution between 2014 and 2018. Diagnosis was determined by histologic type, grade, and myometrial invasion. Concordance rate, sensitivity, and specificity of preoperative diagnosis and intraoperative frozen diagnosis were calculated, in comparison to the final pathologic diagnosis.

RESULTS

Preoperative and intraoperative diagnoses showed no statistically significant difference in determining histologic type and grade (P = 0.152). Intraoperative diagnosis showed higher sensitivity for endometrioid carcinoma grade 3 and other types, and higher specificity for grade 1. For myometrial invasion, intraoperative diagnosis showed significantly higher concordance rate than preoperative MRI findings (P < 0.01). Intraoperative diagnosis showed higher sensitivity and specificity in patients with and without myometrial invasion, respectively.

CONCLUSION

Higher agreement between intraoperative and final diagnoses, especially in myometrial invasion, suggests that intraoperative frozen section is a good indicator for appropriate surgical procedure decision making.

Learning Curve for Ultrasound Assessment of Myometrial Infiltration in Endometrial Cancer Visualizing Videoclips: Potential Implications for Training

BACKGROUND

Diagnostic accuracy for estimating myometrial infiltration by ultrasound in endometrial cancer requires experience. The objective of this study is to determine the learning curve (LC) for assessing myometrial infiltration in cases of endometrial cancer using transvaginal ultrasound (TVS).

METHODS

Five trainees (one staff radiologist and four fourth-year OB/GYN residents) participated in this study. All trainees had experience in performing TVS, but none of them had specific training on the assessment of myometrial infiltration. Trainees were given one specific lecture about the topic, and then they observed videoclips from 10 cases explained by the trainer. After this, all trainees visualized 45 videoclips of uterine ultrasound scans of endometrial cancer cases. The assessment of myometrial infiltration was based on the subjective impression. Definitive histology was used as a reference standard. Trainees stated whether myometrial infiltration was ≥50% or <50%. LC-CUSUM and standard CUSUM graphics were plotted to determine how many cases were needed to reach competence, allowing a mistake rate of 15%.

RESULTS

All trainees completed the study. LC-CUSUM graphics showed that three trainees reached competence at the 33rd, 35th and 36th case, respectively. All three of them kept the process under control after reaching competence. One trainee reached competence but did not maintain it in the cumulative analysis. One trainee did not reach competence.

CONCLUSION

Our study suggests that 30-40 cases would be needed to be trained for assessing myometrial infiltration by TVS by visual interpretation of videoclips by most trainees.

Institutional Accuracy Matters: How the Correlation between Frozen Section and Final Pathology Depends on Institutes while Evaluating Lymph Node Involvement in Endometrial Adenocarcinoma

Background and Purpose: The frozen section analysis results help determine the appropriate surgery and treatment for patients with endometrial adenocarcinoma. This study investigates the degree of compliance between the results of frozen section analysis and final pathology reports in patients with endometrial cancer. Methods: This study included 357 patients with endometrial adenocarcinoma who underwent operation, follow-up, and treatment at our hospital. The patients’ demographic, clinical, surgical, and pathological data were retrospectively analyzed. We compared the results of the frozen section and pathological specimens in terms of final pathology, tumor grade, myometrial invasion, tumor size, and lymphovascular system involvement (LVSI). Results: The frozen section analysis and final pathology results for tumor size and LVSI were significantly correlated when patients were divided by tumor type (tumor size: P=0.006, LVSI: P=0.024) or by risk for lymph node involvement (P=0.000). Overall, the frozen section analysis had an accuracy of 70% for tumor grades. The histological results of the frozen section analysis had an accuracy of 77.1% for type 1 tumors and 72.7% for type 2 tumors. Overall, the frozen section analysis had an accuracy of 95% for myometrial invasion. Conclusion: Intraoperative frozen section analysis can prevent unnecessary lymph node dissection when performed at qualified institutions.

Transvaginal Ultrasound Versus Magnetic Resonance Imaging for Assessing Myometrial Infiltration in Endometrioid Low Grade Endometrial Cancer: A Prospective Study

OBJECTIVE

To compare the diagnostic accuracy of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) for assessing myometrial infiltration (MI) in patients with low grade endometrioid endometrial cancer.

METHODS

Observational prospective study performed at a single tertiary care center from 2016 to 2020, comprising 156 consecutive patients diagnosed by endometrial sampling as having an endometrioid grade 1/grade 2 endometrial cancer. TVS and MRI were performed prior to surgical staging for assessing MI, which was estimated using subjective examiner's impression and Karlsson's method for both TVS and MRI. During surgery, intraoperative assessment of MI was also performed. Definitive pathological study considered as reference standard. Diagnostic accuracy for ultrasound, MRI, and intraoperative biopsy was estimated and compared.

RESULTS

Sensitivity and specificity of TVS for detecting deep MI were 75 and 73.5% for subjective impression and 65 and 70% for Karlsson method, respectively (P = .54). Sensitivity and specificity of MRI for detecting deep MI were 80 and 87% for subjective impression and 70 and 71.3% for Karlsson method. MRI subjective impression showed a significant better specificity than MRI Karlsson method (P = .03). MRI showed better specificity than TVS when subjective impression was considered (P <.05), but not for Karlsson method. Sensitivity and specificity of intraoperative were 75 and 97%, respectively. Intraoperative biopsy showed better specificity than ultrasound and MRI either using examiner's impression or Karlsson method (P <.05).

CONCLUSIONS

MRI revealed a significant higher specificity than TVS when assessing deep myometrial infiltration. However, the intraoperative biopsy offers a significant better diagnostic accuracy than preoperative imaging techniques.

Preoperative prediction of high-risk endometrial cancer by expert and non-expert transvaginal ultrasonography, magnetic resonance imaging, and endometrial histology

OBJECTIVE

To identify women with high-risk endometrial cancers using expert and non-expert transvaginal ultrasonography (TVS) and MRI.

STUDY DESIGN

Myometrial involvement was prospectively evaluated in patients with atypical hyperplasia or endometrial cancer on ultrasound by non-experts at first visit (non-expert-TVS: n = 266) and experts (expert-TVS: n = 188) at second visit. MRI (n = 175) was performed when high-risk cancer was suspected on non-expert-TVS. Preoperatively, high-risk cancer was defined as myometrial involvement ≥50 %, or preoperative unfavorable tumor histology (grade 3 endometrioid, non-endometrioid tumors, or tumor in cervical biopsies) obtained by endometrial sampling or hysteroscopic biopsies. Preoperative evaluations were compared with final histopathology obtained at surgery, high-risk cancer being defined as unfavorable tumor histology or patients with FIGO stage ≥1b.

RESULTS

Preoperative unfavorable tumor histology was seen in 64 women and correctly identified 63 of 128 high-risk cancers. Preoperative diagnosis of unfavorable tumor histology or myometrial involvement ≥50 %, i.e. judged high-risk, had an area under the curve (AUC), sensitivity, and specificity of 79.5 %, 93.8 %, 65.2 % on non-expert-TVS; 85.5 %, 84.4 %, 86.5 % on expert-TVS, and 85.4 %, 89.6 %, 81.2 % on MRI. AUC values were not significantly different between MRI and expert-TVS, but lower on non-expert-TVS (p < 0.02). However, sensitivity was highest on non-expert-TVS, where a low cutpoint for myometrial involvement was used (included potentially deep and difficult evaluations) in contrast to an exact cutpoint of myometrial involvement ≥50 % used on expert-TVS and MRI. The highest AUC, 88.6 %, was seen when MRI was performed in patients with myometrial involvement ≥50 %, determined on non-expert TVS. Sensitivity was reduced to 85.9 %, while specificity increased to 91.3 %. Thus, MRI was needed for risk classification in only 104 (39 %) patients.

CONCLUSION

Diagnostically, expert-TVS and MRI were comparable and superior to non-expert-TVS. However, non-expert-TVS classified all patients with unclear myometrial involvement ≥50 %, and thereby only misdiagnosed 6.2 % of high-risk cases. Non-expert-TVS combined with MRI when myometrial involvement was ≥50 % on non-expert-TVS was a simple and effective method comparable with expert imaging to identify low- and high-risk cancer and select patients for SLND. Addition of MRI to the diagnostic regimen was needed in only 39 % of our patients.

Brazilian Society of Surgical Oncology guidelines for surgical treatment of endometrial cancer in regions with limited resources

BACKGROUND

Approximately 70% of cancer-related deaths occur in low- and middle-income countries. In addition to social and racial inequalities, treatment options in these countries are usually limited because of the lack of trained staff and equipment, limited patient access to health services, and a small number of clinical guidelines.

OBJECTIVES

The Brazilian Society of Surgical Oncology developed this guideline to address these barriers and guide physicians treating patients with endometrial cancer (EC) in regions with limited resources and few specialized centers.

METHODS

The guideline was prepared from 10 January to 25 October 20192019 by a multidisciplinary team of 56 experts to discuss the main obstacles faced by EC patients in Brazil. Thirteen questions considered critical to the surgical treatment of these patients were defined. The questions were assigned to groups that reviewed the literature and drafted preliminary recommendations. Following a review by the coordinators and a second review by all participants, the groups made final adjustments for presentations in meetings, classified the level of evidence, and voted on the recommendations.

RESULTS

For all questions including staging, fertility spearing treatment, genetic testing, sentinel lymph node use, surgical treatment, and other clinical relevant questions, major agreement was achieved by the participants, always using accessible alternatives.

CONCLUSIONS

It is possible to provide adequate treatment for most EC patients in resource-limited areas, but the first option should be referral to specialized centers with more resources.

FXYD5/Dysadherin, a Biomarker of Endometrial Cancer Myometrial Invasion and Aggressiveness: Its Relationship With TGF-β1 and NF-κB Pathways

Objective: Endometrial cancer (EC) is the second most common gynecological cancer worldwide. Myometrial invasion (MI) is a key event in EC dissemination. This study aimed to evaluate FXYD5/dysadherin (FXYD5/Dys) expression in EC tissue and uterine aspirate (UA) biopsies and to assess molecular/functional changes associated with its expression in cellular models. Methods: FXYD5/Dys messenger RNA (mRNA) levels were determined in EC tissue and UA biopsies. FXYD5/Dys expression was evaluated in EC RNAseq data from The Cancer Genome Atlas (TCGA) and GENEVESTIGATOR tools. FXYD5/Dys impact on E-cadherin expression and cell behavior was assessed in EC Hec1a cells treated with transforming growth factor (TGF)-β1, stably transfected with ETV5, and transiently transfected with FXYD5/Dys small interfering RNA (siRNA) or pcDNA3-FXYD5/Dys plasmid. Results: FXYD5/Dys was associated with EC aggressiveness, finding high mRNA levels in tumors depicting MI > 50%, Grade 3, and intermediate/high risk of recurrence. FXYD5/Dys was highly expressed at the tumor invasive front compared to the superficial area. Most results were recapitulated in UA biopsies. FXYD5/Dys modulation in Hec1a cells altered cell migration/adhesion and E-cadherin expression. TGF-β1 treatment of Hec1a cells induced FXYD5/Dys expression. TCGA-UCEC RNAseq analysis revealed a positive correlation between FXYD5/Dys, TGF-β1, and plasminogen activator inhibitor (PAI)-1 mRNA levels. FXYD5/Dys induced nuclear factor (NF)-κB pathway activation in Hec1a cells. FXYD5/Dys mRNA levels positively correlated with transcriptional activation of NF-κB p65-regulated genes. Survival analysis revealed patient segregation into low- and high-risk groups, the latter depicting the highest FXYD5/Dys, PAI-1, tumor necrosis factor (TNF)-α, and TGF-β1 mRNA levels and shorter survival rates. Conclusion: FXYD5/Dys is a novel biomarker of EC progression related to TGF-β1 and NF-κB pathways that collectively promote tumor dissemination and result in poor patient prognosis.

Sentinel Pelvic Lymph Node Dissection by Natural Orifices Transvaginal Endoscopic Surgery Approach after Indocyanine Green Dye Detection in Early Endometrial Cancer of Posthysterectomy Patient

There was a case of 57-year-old female who was done the natural orifices transvaginal endoscopic surgery (NOTES) hysterectomy and bilateral salpingo-oophorectomy for benign disease. However, her biopsy result was Grade 1 endometrioid adenocarcinoma, and she was incidentally diagnosed as endometrial cancer. She was uneventful apart from that finding. She underwent the sentinel pelvic lymph node dissection with indocyanine green-guided NOTES approach for complete staging. This technique may be helpful to maximize the complete staging in early endometrial cancer as well as it can minimize the morbidity-related lymphadenectomy. In conclusion, in spite of a new technique for NOTEs, it can be safe and cost-effective for patients.

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.

Transvaginal ultrasound versus magnetic resonance imaging for preoperative assessment of myometrial infiltration in patients with endometrial cancer: a systematic review and meta-analysis

Objective

To compare the diagnostic accuracy of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) for detecting myometrial infiltration (MI) in endometrial carcinoma.

Methods

An extensive search of papers comparing TVS and MRI in assessing MI in endometrial cancer was performed in MEDLINE (PubMed), Web of Science, and Cochrane Database from January 1989 to January 2017. Quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool.

Results

Our extended search identified 747 citations but after exclusions we finally included in the meta-analysis 8 articles. The risk of bias for most studies was low for most 4 domains assessed in QUADAS-2. Overall, pooled estimated sensitivity and specificity for diagnosing deep MI were 75% (95% confidence interval [CI]=67%–82%) and 82% (95% CI=75%–93%) for TVS, and 83% (95% CI=76%–89%) and 82% (95% CI=72%–89%) for MRI, respectively. No statistical differences were found when comparing both methods (p=0.314). Heterogeneity was low for sensitivity and high for specificity for TVS and MRI.

Conclusion

MRI showed a better sensitivity than TVS for detecting deep MI in women with endometrial cancer. However, the difference observed was not statistically significant.

RERT: A Novel Regression Tree Approach to Predict Extrauterine Disease in Endometrial Carcinoma Patients

Some aspects of endometrial cancer (EC) preoperative work-up are still controversial, and debatable are the roles played by lymphadenectomy and radical surgery. Proper preoperative EC staging can help design a tailored surgical treatment, and this study aims to propose a new algorithm able to predict extrauterine disease diffusion. 293 EC patients were consecutively enrolled, and age, BMI, children’s number, menopausal status, contraception, hormone replacement therapy, hypertension, histological grading, clinical stage, and serum HE4 and CA125 values were preoperatively evaluated. In order to identify before surgery the most important variables able to classify EC patients based on FIGO stage, we adopted a new statistical approach consisting of two-steps: 1) Random Forest with its relative variable importance; 2) a novel algorithm able to select the most representative Regression Tree (RERT) from an ensemble method. RERT, built on the above mentioned variables, provided a sensitivity, specificity, NPV and PPV of 90%, 76%, 94% and 65% respectively, in predicting FIGO stage > I. Notably, RERT outperformed the prediction ability of HE4, CA125, Logistic Regression and single cross-validated Regression Tree. Such algorithm has great potential, since it better identifies the true early-stage patients, thus providing concrete support in the decisional process about therapeutic options to be performed.

Assessment of the Role of Intraoperative Frozen Section in Guiding Surgical Staging for Endometrial Cancer

Objective

The aim of this study was to assess the role of intraoperative frozen section (FS) in guiding decision making for surgical staging of endometrioid endometrial cancer (EC).

Methods

Medical records were collected retrospectively on 112 patients with endometrioid EC, who underwent total hysterectomy and bilateral salpingo-oophorectomy at the University of Arizona Medical Center from January 1, 2010, to December 31, 2014. Only patients with endometrioid adenocarcinoma, grade 1, less than 50% myometrial invasion, and tumor size less than 2 cm determined by intraoperative FS omitted lymphadenectomy; otherwise, surgical staging was performed with lymph node dissection. The FS results were compared with the permanent paraffin sections (PSs) to assess the diagnostic accuracy.

Results

The concordance rate of different variables between FS and PS in EC was 100%, 89.3% (100/112), 97.3% (109/112), and 95.5% (107/112), respectively, with respecting to histological subtype, grade, myometrial invasion, and tumor size. Diagnostic accurate rate of combined risk factors deciding surgical staging at the time of FS was 95.5% (107/112), and the discordance rate of all risk factors considered between FS and PS was 4.5%, resulting 3 cases (2.7%) undertreated and 2 cases (1.8%) overtreated.

Conclusions

Despite nonideal FS evaluation, intraoperative FS diagnosis for EC is highly reliable by providing guidance for the intraoperative decisions of surgical staging at our institution, and such guidelines may be referenced by the institutions with sufficient gynecologic pathology expertise.

Robotic surgery in supermorbidly obese patients with endometrial cancer

OBJECTIVE

Morbid obesity is a known risk factor for the development of endometrial cancer. Several studies have demonstrated the overall feasibility of robotic-assisted surgical staging for endometrial cancer as well as the benefits of robotics compared with laparotomy. However, there have been few reports that have evaluated robotic surgery for endometrial cancer in the supermorbidly obese population (body mass index [BMI], ≥50 kg/m(2)). We sought to evaluate safety, feasibility, and outcomes for supermorbidly obese patients who undergo robotic surgery for endometrial cancer, compared with patients with lower body mass indices.

STUDY DESIGN

We performed a retrospective chart review of 168 patients with suspected early-stage endometrial adenocarcinoma who underwent robotic surgery for the management of their disease. Analysis of variance and univariate logistic regression were used to compare patient characteristics and surgical variables across all body weights. Cox proportional hazard regression was used to determine the impact of body weight on recurrence-free and overall survival.

RESULTS

The mean BMI of our cohort was 40.9 kg/m(2). Median follow up was 31 months. Fifty-six patients, 30% of which had grade 2 or 3 tumors, were supermorbidly obese with a BMI of ≥50 kg/m(2) (mean, 56.3 kg/m(2)). A comparison between the supermorbidly obese and lower-weight patients demonstrated no differences in terms of length of hospital stay, blood loss, complication rates, numbers of pelvic and paraaortic lymph nodes retrieved, or recurrence and survival. There was a correlation between BMI and conversion to an open procedure, in which the odds of conversion increased with increasing BMI (P = .02).

CONCLUSION

Offering robotic surgery to supermorbidly obese patients with endometrial cancer is a safe and feasible surgical management option. When compared with patients with a lower BMI, the supermorbidly obese patient had a similar outcome, length of hospital stay, blood loss, complications, and numbers of lymph nodes retrieved.

Predictors of limph node metastasis in endometrial cancer

INTRODUCTION

Endometrial cancer is the most common gynecologic malignancy in developed countries. The adequate surgical staging proposed by FIGO (International Federation for Gynaecology and Obstetrics) advocates lymphadenectomy; however, it does not establish the indications, the type and the extent of lymphadenectomy, thus generating multiple controversies.

METHODS

Retrospective, analytical study of patients treated surgically for endometrial adenocarcinoma in the Oncological Institute "Prof. Dr. Ion Chiricuţă" Cluj-Napoca (IOCN) between January 2008 and December 2012 - 709 cases eligible for the study.

RESULTS

206 pelvic and/or paraaortic lymphadenectomies were performed, the average number of excised lymph nodes being 15.6. Overall in 4.4% of patients the lymph nodes were affected by metastases. The presence of each risk factor analysed was statistically significantly associated with lymph node metastasis (p<0.05). Age above 55 years was statistically significantly associated (p<0.05) with the presence of negative prognostic factors in the study.

CONCLUSIONS

The analysed histopathological and clinical prognostic factors were statistically significantly associated with lymphatic dissemination in endometrial cancer. We recommend treating endometrial cancer in tertiary centres by surgeons or gynaecologists-oncologists with experience in extensive peritoneal and retroperitoneal surgery.

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.

The role of frozen section in surgical staging of low risk endometrial cancer

BACKGROUND

The role of frozen section (FS) in intraoperative decision making for surgical staging of endometrial cancer is controversial. Objective of this study is to assess the agreement rate between the FS and paraffin section (PS); and the potential impact of the role of FS in the intra-operative decision making for the complete surgical staging in low risk endometrial cancer.

METHODS

This is a retrospective analysis of patients diagnosed with intra-operative FS stage I, grade I or II endometrial cancer from 1995-2004. FS results were compared with final pathology results with regard to tumor grade, depth of myometrial invasion, cervical involvement, lymphovascular invasion, and lymph node involvement. Agreement statistic with kappa was calculated using SPSS statistical software. Categorical variables were tested using chi-square test with p value of ≤0.05 being statistically significant.

RESULTS

Of the 457 patients with endometrial cancer, 146 were evaluated by intra-operative FS and met inclusion criteria. FS results were in disagreement with permanent section in 35% for the grade (kappa 0.58, p = 0.003), 28% for depth of myometrial invasion (kappa 0.61, p<0.0001), 13% for cervical involvement (kappa 0.78, p = 0.002), and 32% for lymphovascular invasion (kappa 0.6, p = 0.01). Permanent pathology upstaged 31.9% & 23.2% of FS stage IA, & IB specimen respectively. Lymph node dissection was done in 56.8%. Lymph node metastasis was identified in 8.4%. Use of intraoperative FS would have resulted in suboptimal surgical treatment in 13% stage IA and 6.6% of stage IB patients respectively by foregoing lymphadenectomy.

CONCLUSION

A significant number of patients with low risk endometrial cancer by FS were upstaged and upgraded on final pathology. Before placing absolute reliance on intraoperative FS to undertake complete surgical staging, the inherent limitation of the same in predicting final stage and grade highlighted by our data need to be carefully considered.