Predictors of non-sentinel lymph node (non-SLN) metastasis in patients with sentinel lymph node (SLN) metastasis in endometrial cancer

Sentinel lymph node mapping and staging in endometrial cancer: A Society of Gynecologic Oncology literature review with consensus recommendations

The emphasis in contemporary medical oncology has been "precision" or "personalized" medicine, terms that imply a strategy to improve efficacy through targeted therapies. Similar attempts at precision are occurring in surgical oncology. Sentinel lymph node (SLN) mapping has recently been introduced into the surgical staging of endometrial cancer with the goal to reduce morbidity associated with comprehensive lymphadenectomy, yet obtain prognostic information from lymph node status. The Society of Gynecologic Oncology's (SGO) Clinical Practice Committee and SLN Working Group reviewed the current literature for preparation of this document. Literature-based recommendations for the inclusion of SLN assessment in the treatment of patients with endometrial cancer are presented. This article examines.

Sentinel Lymph Node Mapping in Patients with Endometrial Carcinoma: Less Can Be More

PURPOSE OF REVIEW

The role and extent of lymphadenectomy for endometrial carcinoma has been debated for over 30 years. Many clinicians argue that there is therapeutic value for lymphadenectomy in patients deemed to be "at risk", a designation not universally defined, despite the lack of randomized data supporting this argument. However, lymphadenectomy is associated with morbidity, including lower extremity lymphedema. Sentinel lymph node (SLN) mapping is emerging as a viable alternative to comprehensive lymphadenectomy in the surgical staging of patients with endometrial cancer.

RECENT FINDINGS

Nodal disease status is an important prognostic and predictive factor. Surgical staging with lymphadenectomy remains an important part of the treatment of patients with newly diagnosed endometrial carcinoma despite the dispute regarding its therapeutic value. Many clinicians have argued for abandoning lymphadenectomy altogether; however, this too is not ideal, as it may lead to under-treatment due to inadequate staging or over-treatment with toxic therapies.

SUMMARY

SLN mapping has emerged as a viable compromise between a comprehensive lymphadenectomy and no lymph node sampling in the surgical staging of these patients, and may lead to reduced morbidity risks. In this review, we present the currently available data in this area of research, as well as our experience with SLN mapping.

The Combination of Preoperative Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography and Sentinel Lymph Node Mapping in the Surgical Management of Endometrioid Endometrial Cancer

OBJECTIVE

The goal of this study was to evaluate the combination of sentinel lymph node (SLN) mapping and F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) scan in detection of lymph node involvement in patients with endometrioid endometrial cancer (EEC).

METHODS/MATERIALS

Ninety-five patients with EEC who had preoperative PET/CT imaging and underwent SLN mapping were retrospectively analyzed. Methylene blue dye was used and injected to the cervix at 3- and 9-o'clock positions (a total of 4 mL). Pelvic lymphadenectomy was performed on all of the patients after SLN mapping. If the SLN was negative in the initial hematoxylin and eosin staining, an ultrastaging study was performed for the SLNs.

RESULTS

Sentinel lymph nodes were detected in 77 (81.1%) of 95 patients, with a mean of 2.95 SLNs. There was only 1 case (1.4%) with a positive SLN in the intraoperative frozen section examination in those patients with negative PET/CT findings and in whom SLNs were detected (n = 70). Among the remaining 69 patients with negative preoperative PET/CT findings and negative frozen section results for the SLNs, there were 2 patients with SLN involvement in the final ultrastaging pathology. In the patient-based analyses, the sensitivity, specificity, and positive and negative predictive values of the PET/CT and SLN frozen section were 33%, 100%, 100%, and 97.1%, respectively.

CONCLUSIONS

As no metastases in the nonsentinel pelvic lymph nodes were found in patients with EEC who had both negative PET/CT findings and frozen section results of the SLNs in both hemipelvises, we suggest using both methods to reduce the incidence of unnecessary systematic lymphadenectomy.

Are preoperative histology and MRI useful for classification of endometrial cancer risk?

Background

The 2010 guidelines of the French National Cancer Institute (INCa) classify patients with endometrial cancer into three risk groups for lymph node invasion and recurrence on the basis of MRI and histological analysis of an endometrial specimen obtained preoperatively. The classification guides therapeutic choices, which may include pelvic and/or para-aortic lymphadenectomy. The purpose of this study was to evaluate the diagnostic performance of preoperative assessment to help identify intermediate- or high-risk patients requiring lymphadenectomy.

Methods

The study included all patients who underwent surgery for endometrial cancer between January 2010 and December 2013 at either Rennes University Hospital or Vannes Regional Hospital. The criteria for eligibility included a preoperative assessment with MRI and histological examination of an endometrial sample. A histological comparison was made between the preoperative and surgical specimens.

Results

Among the 91 patients who underwent a full preoperative assessment, the diagnosis of intermediate- or high-risk endometrial cancer was established by MRI and histology with a sensitivity of 70 %, specificity of 82 %, positive predictive value (PPV) of 87 %, negative predictive value (NPV) of 61 %, positive likelihood ratio (LR+) of 3.8 and negative likelihood ratio (LR-) of 0.3. The risk group was underestimated in 32 % of patients and overestimated in 7 % of patients. MRI underestimated endometrial cancer stage in 20 % of cases, while endometrial sampling underestimated the histological type in 4 % of cases and the grade in 9 % of cases.

Conclusion

The preoperative assessment overestimated or underestimated the risk of recurrence in nearly 40 % of cases, with errors in lesion type, grade or stage. Erroneous preoperative risk assessment leads to suboptimal initial surgical management of patients with endometrial cancer.

Quality of Care for Cervical and Endometrial Cancer Patients: The Impact of Different Techniques of Sentinel Lymph Node Mapping on Patient Satisfaction

OBJECTIVES

The purpose of this study was to assess the quality of care in patients who underwent sentinel lymph node (SLN) mapping for endometrial and cervical cancer staging, and evaluate the impact of different techniques on patient satisfaction, i.e. radiotracer Tc99m versus indocyanine green (ICG) or methylene blue injection.

METHOD

Women with preoperative stage I endometrial cancer or stage I (1A2-1B1) cervical cancer who underwent surgical staging, including SLN mapping, were considered for this study. Patient satisfaction was assessed using the European Organisation for Research and Treatment of Cancer IN-PATSAT32 questionnaire. Women were classified into two groups according to the different nodal mapping techniques: intracervical preoperative injection of Tc99m nanocolloid + intraoperative blue dye (Group 1) versus intraoperative cervical injection of ICG or blue dye (Group 2). Differences in patient satisfaction scores between the groups were analyzed.

RESULTS

Of the 178 eligible women, 143 were included in the study (endometrial cancer n = 106, cervical cancer n = 37): 57 underwent SLN mapping with Tc99m and blue dye (Group 1), and 86 women were mapped intraoperatively with blue dye alone or ICG (Group 2). Analysis of IN-PATSAT32 questionnaire scores showed a higher patient satisfaction score for patients in Group 2 (p = 0.001), which was independent of the physician and surgical outcomes evaluated. The scores were statistically better for Group 2, and also in rating doctors (p = 0.0001), nurses (p = 0.006), and care and services organizations (p = 0.001).

CONCLUSIONS

Cervical and endometrial cancer patients who underwent SLN mapping by ICG or blue dye perceived a better quality of care when compared with those patients who underwent the combined radiocolloid and blue dye technique.

[Early-stage endometrial cancer: Sentinel node or lymphadenectomy?]

The endometrial cancers are mainly discovered at an early stage justifying a less aggressive treatment. The therapeutic choices are today based on preoperative classifications themselves based on histo-prognostic factors of the tumor and its extension measured in MRI: consequently, lymph node dissection in case of low and intermediate risk cancer is not systematically achieved. But a number of patients have lymph node involvement finally, probably justifying an adapted surgical and adjuvant treatment. The technique of sentinel node would compensate the weaknesses of preoperative prognostic evaluation. This new operative technique needs to be precised and evaluated: the topics subject to discussion are the technical implementation, the definition of its quality standards and the management of its histological results especially in cases of low volume lymph node metastasis.

Laparoscopic Indocyanine Green Sentinel Lymph Node Mapping in Endometrial Cancer

Background

In endometrial cancer (EMCA), indocyanine green (ICG) sentinel lymph node (SLN) mapping has been reported, mainly in conjunction with robotic surgery.

Objective

We aimed to evaluate detection rates, sensitivity, and false negative (FN) rate of laparoscopic ICG SLN mapping in EMCA, and to evaluate differences in surgical outcomes between patients subjected to SLN biopsy only versus lymphadenectomy.

Methods

A retrospective analysis of EMCA patients undergoing ICG SLN mapping ± pelvic (PLND) and/or para-aortic lymphadenectomy (PALND) was performed. Detection rates were calculated for the entire cohort. Sensitivity and FN rates were calculated for patients undergoing lymphadenectomy after SLN mapping, and surgical outcome was compared among patients undergoing SLN mapping only versus lymphadenectomy.

Results

Of 75 patients, 33 underwent SLN mapping and 42 underwent SLN mapping followed by PLND/PALND. Overall and bilateral detection rates were 96 % (72/75) and 88 % (66/75), respectively, and the median number of removed SLNs, pelvic non-SLNs (NSLN) and para-aortic NSLNs was 3, 27, and 19, respectively. With a FN rate of 8.3 %, only one patient had bilateral FN SLNs and a metastatic para-aortal NSLN. Estimated blood loss (EBL) and operative (OR) time were significantly lower in patients undergoing SLN mapping only. No differences in complication rates between patients undergoing SLN mapping only and patients undergoing lymphadenectomy were recorded.

Conclusions

Laparoscopic ICG SLN mapping has excellent overall and bilateral detection rates and a low FN rate. Compared with lymphadenectomy, SLN biopsy is associated with significantly lower EBL and shorter OR time.

Low-Volume Lymph Node Metastasis Discovered During Sentinel Lymph Node Mapping for Endometrial Carcinoma

PURPOSE

The aim of this study was to characterize treatment patterns and oncologic outcomes in patients with low-volume lymph node metastasis (isolated tumor cells [ITCs] and micrometastasis [MM]) discovered during sentinel lymph node (SLN) mapping for endometrial carcinoma.

METHODS

We identified endometrial cancer cases treated surgically from September 2005 to April 2013 in which SLN mapping was performed. MM was defined as tumor within a lymph node measuring >0.2 mm but <2.0 mm, and ITCs were those measuring ≤0.2 mm.

RESULTS

Overall, 844 patients, with a median age of 61 years (range 30-90), met the inclusion criteria. Histology was as follows: endometrioid, 724 (85.8 %) patients; serous, 104 (12.3 %) patients; and clear cell, 16 (1.9 %) patients. The median number of lymph nodes resected was six (range 0-60), and the median number of SLNs was two (range 0-15). Overall, 753 (89.2 %) patients were node-negative, 23 (2.7 %) had ITCs only, 21 (2.5 %) had MM only, and 47 (5.6 %) had macrometastasis. Adjuvant chemotherapy was administered to 106 (14 %) of 753 node-negative patients, 19 (83 %) of 23 patients with ITCs, 17 (81 %) of 21 patients with MM, and 42 (89 %) of 47 with macrometastasis. Median follow-up was 26 months (range 0-108). Three-year recurrence-free survival was as follows: node-negative patients, 90 % (±1.5); ITCs only, 86 % (±9.4); MM only, 86 % (±9.7); and macrometastasis, 71 % (±7.2) [p < 0.001].

CONCLUSIONS

Patients with ITCs and MM frequently received adjuvant chemotherapy and had improved oncologic outcomes in comparison to those with macrometastasis to the lymph nodes. Further prospective study is needed to determine optimal post-resection management in patients with ITCs or MM alone.

Sentinel Lymph Node Mapping With Near-Infrared Fluorescent Imaging Using Indocyanine Green: A New Tool for Laparoscopic Platform in Patients With Endometrial and Cervical Cancer

Indocyanine green (ICG) represents a feasible alternative to the more traditional methods of sentinel lymph node (SLN) mapping, and interest in this promising tracer is growing. This report outlines our experience with ICG in a minimally invasive laparoscopic approach in women with endometrial cancer and cervical cancer using the Storz SPIES ICG near-infrared fluorescence imaging technology. A total of 49 patients with clinical stage I endometrial cancer (n = 40) or stage I cervical cancer (n = 9) were retrospectively reviewed. All patients had undergone simple or radical laparoscopic hysterectomy with pelvic and/or aortic lymphadenectomy and SLN mapping by means of an intracervical injection of ICG dye at the 3 o'clock and 9 o'clock locations after the induction of general anesthesia. The detection rate of ICG was 100% (49 of 49). The rate of bilateral SLN detection was 86% (42 of 49). Positive lymph nodes were found in 6 patients (12%), with at least 1 positive SLN. The sensitivity and negative predictive value of SLN detection were 100%. All procedures were successfully completed without conversion to open laparotomy, and no intraoperative or postoperative complications occurred. In our preliminary experience, ICG showed a high overall detection rate, and bilateral mapping appears to be a feasible alternative to the more traditional methods of SLN mapping in patients with endometrial cancer and cervical cancer. Laparoscopic SLN mapping with ICG appears to be safe, easy, and reproducible, with a positive impact on patient management.

Sentinel lymph node procedure in endometrial cancer: A systematic review and proposal for standardization of future research

OBJECTIVES

Sentinel lymph node (SLN) procedure could be an attractive solution to the debate on lymphadenectomy in endometrial cancer; however challenges to interpreting the literature include marked heterogeneity across studies, a wide variety of injection techniques and a lack of uniformly accepted definitions for important outcomes. We aim to critically appraise the published literature and streamline terminology and methodology for future studies in this field.

METHODS

We conducted a PubMed search and included all original research of endometrial cancer patients having undergone SLN procedure with an n>30. Data collected included injection technique, unilateral, bilateral, and para-aortic detection rates, and ultrastaging results. When different definitions were used for reporting outcomes, we recalculated the original study results according to our proposed definitions. Data was analyzed using descriptive statistics.

RESULTS

Seventeen studies met our inclusion criteria. Injection sites were categorized into cervical versus corporeal. Overall detection rates ranged from 60 to 100%; studies with n>100 all had overall detection rates of >80%. Bilateral detection rates were higher with a combination of two injection agents. Para-aortic mapping was most frequent after corporeal injection techniques (39%), and was higher after deep vs. standard cervical injection (17% vs. 2%). The proportion of metastatic lymph nodes diagnosed through ultrastaging was high (around 40%) and ultrastaging of SLN upstaged approximately 5% of patients. Retrospectively applying a surgical algorithm revealed a sensitivity of 95%, a negative predictive value of 99%, and a false negative rate of 5% (with only 9 false negative cases remaining in total).

CONCLUSION

Results of SLN research for endometrial cancer are promising. We believe that in future studies, uniform reporting is needed to improve our understanding of the safety and feasibility of SLN in EC. We propose 2 strategies: a checklist of elements to include in future reports and the standardization of key definitions.