Sentinel lymph node mapping for grade 1 endometrial cancer: is it the answer to the surgical staging dilemma?

One-Step Nucleic Acid Amplification Analysis of Sentinel Nodes in Endometrial Cancer Versus Ultrastaging: First Long-Term Follow-Up Data of Discordant Cases

AIMS

Endometrial cancer (EC) is the most common gynecological cancer worldwide and its incidence is rising. The cornerstone of its management is surgical treatment with nodal staging. A monocentric study investigating the potential of the molecular biology method of one-step nucleic acid amplification (OSNA) in sentinel lymph node (SLN) analysis was conducted at our institution between April 2016 and January 2018. Histopathological ultrastaging was used as the reference standard for SLN examination and OSNA as the index test. The aim of this study was to assess the long-term outcome of patients with discordant SLN and OSNA results. To our knowledge, this is the first study exploring this issue.

METHODS AND RESULTS

Patients were followed in line with the current ESMO/ESGO/ESTRO recommendations. The institutional electronic database was retrospectively searched for patients' follow-up data from April 2016 till March 2023. Only patients who provided a written valid consent and had a positive OSNA and negative ultrastaging of their SLN analysis were included in the study. The primary endpoint was the retrospective analysis of their clinical outcome. Data from 58 patients enrolled into our previous study were reviewed and 12 discordant patients who met the inclusion criteria for this study were identified. The median follow-up was 83 months. Disease recurrence was detected in 3 (25%) patients, two of these were nodal and both patients died. One patient had a solitary lung metastasis which was surgically treated, and the patient was disease-free during the whole study period.

CONCLUSION

The recurrence rate of patients included in the study was in the intermediate-high and high-risk group range, and hence, higher than expected based on ultrastaging results. Furthermore, benign epithelial inclusions do not seem to adversely affect OSNA SLN analysis in EC patients.

Optimizing the Sensitivity of a Pelvic Sentinel Node Algorithm Requires a Hybrid Algorithm Combining Indocyanine Green Based Mapping and the Removal of Non-Mapped Nodes at Defined Anatomic Positions

AIM OF THE STUDY

to investigate the incidence of non-mapped isolated metastatic pelvic lymph nodes at pre-defined anatomical positions.

PATIENTS AND METHODS

Between June 2019 and January 2024, women with uterine-confined endometrial cancer (EC) deemed suitable for robotic surgery and the detection of pelvic sentinel nodes (SLNs) were included. An anatomically based, published algorithm utilizing indocyanine green (ICG) as a tracer was adhered to. In women where no ICG mapping occurred in either the proximal obturator and/or the interiliac positions, defined as "typical positions", those nodes were removed and designated as "SLN anatomy". Ultrastaging and immunohistochemistry were applied to all SLNs. The proportion of isolated metastatic "SLN anatomy" was evaluated.

RESULTS

A non-mapping of either the obturator or interiliac area occurred in 180 of the 620 women (29%). In total, 114 women (18.4%) were node-positive and five of these women (4.3%) had isolated metastases in an "SLN anatomy", suggesting a similar lower sensitivity of the ICG-only algorithm.

CONCLUSION

In an optimized SLN algorithm for endometrial cancer, to avoid undetected nodal metastases in 4.3% of node-positive women, if mapping fails in either the proximal obturator or interiliac area, nodes should be removed from those defined anatomic positions, despite mapping at other positions.

Molecular profile in endometrial carcinoma: can we predict the lymph node status? A systematic review and meta-analysis

PURPOSE

Molecular classification of endometrial cancer (EC) has become a promising information to tailor preoperatively the surgical treatment. We aimed to evaluate the rate of lymph node metastases (LNM) in patients with EC according to molecular profile.

METHODS

A systematic review and meta-analysis were performed according to PRISMA guidelines by searching in two major electronic databases (PubMed and Scopus), including original articles reporting lymph node metastases according to the molecular classification of EC as categorized in the ESGO-ESMO-ESP guidelines.

RESULTS

Fifteen studies enrolling 3056 patients were included. Pooled prevalence LNM when considering only patients undergoing lymph node assessment was 4% for POLE-mutated (95%CI: 0-12%), 22% for no specific molecular profile (95% CI: 9-39%), 23% for Mismatch repair-deficiency (95%CI: 10-40%) and 31% for p53-abnormal (95%CI: 24-39%).

CONCLUSIONS

The presence of LNM seems to be influenced by molecular classification. P53-abnormal group presents the highest rate of nodal involvement, and POLE-mutated the lowest.

A selective anatomically based lymph node sampling can replace a side specific pelvic lymphadenectomy in endometrial cancer with failed sentinel node mapping

AIM

To evaluate the locations of metastatic pelvic sentinel nodes (SLN) and the proportion of SLNs outside and within defined typical anatomical positions along the upper paracervical lymphatic pathway (UPP).

PATIENTS AND METHODS

Consecutive women with endometrial cancer (EC) of all risk groups underwent pelvic SLN-detection using cervically injected indocyanine green (ICG). A strict anatomically based algorithm and definitions of SLNs was adhered to. The positions of ICG-defined SLNs were intraoperatively depicted on an anatomical chart. All SLNs were examined using ultrastaging and immunohistochemistry. The proximal third of the obturator fossa and the interiliac area were defined as typical positions. The parauterine lymphovascular tissue (PULT) was separately removed. The proportions of metastatic SLNs, overall and isolated, typically, and atypically positioned were analyzed per woman.

RESULTS

A median of two (range 1-12) SLN metastases along the UPP including the PULT were found in 162 women. 41 of 162 women (25.3 %) had isolated metastases in the obturator fossa harboring 49.1 % of all SLN metastases. Three women (1,9 %) had isolated PULT metastases. SLN metastases outside typical positions were identified in 28/162 women (17.3 %); isolated metastases were seen in seven women (4.3 %), so 95.7 % of pelvic node positive women had at least one metastatic SLN located at a typical position.

CONCLUSION

A selective removal of lymph nodes at typical proximal obturator and interiliac positions and the PULT can replace a full side specific pelvic LND when SLN mapping is unsuccessful. The obturator fossa is the predominant location for metastatic disease.

Establishing guidelines for sentinel lymph node ultrastaging in endometrial cancer

BACKGROUND

Many sentinel lymph node (SLN) ultrastaging protocols for endometrial cancer exist, but there is no consensus method.

OBJECTIVE

This study aims to develop guidelines for size criteria in SLN evaluation for endometrial cancer, to determine whether a single cytokeratin AE1:AE3 immunohistochemical slide provides sufficient data for diagnosis, and to compare cost efficiency between current and limited ultrastaging protocols at a large tertiary care institution.

METHODS

Our current SLN ultrastaging protocol consists of cutting two adjacent paraffin block sections at two levels (L1 and L2), 50 μm apart, with two slides at each level stained with hematoxylin and eosin and cytokeratin AE1:AE3 immunohistochemistry. We retrospectively reviewed digitized L1 and L2 slides of all positive ultrastaged SLNs from patients treated for endometrial cancer between January 2013 and January 2020. SLN diagnosis was defined by measuring the largest cluster of contiguous tumor cells in a single cross section: macrometastasis (>2.0 mm), micrometastasis (>0.2 to ≤2.0 mm or >200 cells), or isolated tumor cells (≤0.2 mm or ≤200 cells). Concordance between L1 and L2 results was evaluated. Cost efficiency between current (two immunohistochemical slides per block) and proposed limited (one immunohistochemical slide per block) protocols was compared.

RESULTS

Digitized slides of 147 positive SLNs from 109 patients were reviewed; 4.1% of SLNs were reclassified based on refined size criteria. Complete concordance between L1 and L2 interpretations was seen in 91.8% of SLNs. A false-negative rate of 0%-0.9% in detecting micrometastasis and macrometastasis using a limited protocol was observed. Estimated charge-level savings of a limited protocol were 50% per patient.

CONCLUSION

High diagnostic accuracy in SLN interpretation may be achieved using a limited ultrastaging protocol of one immunohistochemical slide per block and linear measurement of the largest cluster of contiguous tumor cells. Implementation of the proposed limited ultrastaging protocol may result in laboratory cost savings with minimal impact on health outcomes.

Risk factors associated with false negative rate of sentinel lymph node biopsy in endometrial cancer: a systematic review and meta-analysis

Objective

Currently, sentinel lymph node biopsy (SLNB) is increasingly used in endometrial cancer, but the rate of missed metastatic lymph nodes compared to systemic lymph node dissection has been a concern. We conducted a systematic review and meta-analysis to evaluate the false negative rate (FNR) of SLNB in patients with endometrial cancer and to explore the risk factors associated with this FNR.

Data sources

Three databases (PubMed, Embase, Web of Science) were searched from initial database build to January 2023 by two independent reviewers.

Research eligibility criteria

Studies were included if they included 10 or more women diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I or higher endometrial cancer, the study technique used sentinel lymph node localization biopsy, and the reported outcome metrics included false negative and/or FNR.

Study appraisal and synthesis methods

Two authors independently reviewed the abstracts and full articles. The FNR and factors associated with FNR were synthesized through random-effects meta-analyses and meta-regression.

The results

We identified 62 eligible studies. The overall FNR for the 62 articles was 4% (95% CL 3-5).There was no significant difference in the FNR in patients with high-risk endometrial cancer compared to patients with low-risk endometrial cancer. There was no difference in the FNR for whether frozen sections were used intraoperatively. The type of dye used intraoperatively (indocyanine green/blue dye) were not significantly associated with the false negative rate. Cervical injection reduced the FNR compared with alternative injection techniques. Indocyanine green reduced the FNR compared with alternative Tc-99m. Postoperative pathologic ultrastaging reduced the FNR.

Conclusions

Alternative injection techniques (other than the cervix), Tc-99m dye tracer, and the absence of postoperative pathologic ultrastaging are risk factors for a high FNR in endometrial cancer patients who undergo SLNB; therefore, we should be vigilant for missed diagnosis of metastatic lymph nodes after SLNB in such populations.

Systematic review registration

http://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023433637.

Low-Volume Metastases in Apparent Early-Stage Endometrial Cancer: Prevalence, Clinical Significance, and Future Perspectives

Endometrial cancer (EC) is the most diagnosed gynecologic malignancy, and its incidence and mortality are increasing. The prognosis is highly dependent on the disease spread. Surgical staging includes retroperitoneal evaluation to detect potential lymph node metastases. In recent years, systematic lymphadenectomy has been replaced by sentinel lymph node (SLN) biopsy and ultrastaging, allowing for the detection of macrometastases, micrometastases, and isolated tumor cells (ITCs). Micrometastases and ITCs have been grouped as low-volume metastases (LVM). The reported prevalence of LVM in studies enrolling more than one thousand patients with apparent early-stage EC ranges from 1.9% to 10.2%. Different rates of LVM are observed when patients are stratified according to disease characteristics and their risk of recurrence. Patients with EC at low risk for recurrence have low rates of LVM, while intermediate- and high-risk patients have a higher likelihood of being diagnosed with nodal metastases, including LVM. Macro- and micrometastases increase the risk of recurrence and cause upstaging, while the clinical significance of ITCs is still uncertain. A recent meta-analysis found that patients with LVM have a higher relative risk of recurrence [1.34 (95% CI: 1.07-1.67)], regardless of adjuvant treatment. In a retrospective study on patients with low-risk EC and no adjuvant treatment, those with ITCs had worse recurrence-free survival compared to node-negative patients (85.1%; CI 95% 73.8-98.2 versus 90.2%; CI 95% 84.9-95.8). However, a difference was no longer observed after the exclusion of cases with lymphovascular space invasion. There is no consensus on adjuvant treatment in ITC patients at otherwise low risk, and their recurrence rate is low. Multi-institutional, prospective studies are warranted to evaluate the clinical significance of ITCs in low-risk patients. Further stratification of patients, considering histopathological and molecular features of the disease, may clarify the role of LVM and especially ITCs in specific contexts.

Sentinel lymph node biopsy in endometrial cancer: When, how and in which patients

The role of nodal dissection in patients with endometrial cancer has been intensively studied in several studies. Historically, systematic pelvic and para-aortic lymphadenectomy represented the gold standard surgical treatment to assess potential nodal involvement and consequently define the appropriate stage of the tumor. Over the last years, sentinel node biopsy (SLNB) has been introduced as a more targeted alternative to lymph node dissection for lymph node staging and it has become popular among gynecologic oncologists. However, no level A evidence is still available, and several features of the SLNB technique have been matter of discussion among clinicians and a universally accepted methodology is still not currently available. This narrative review aims to summarize the body of knowledge on SLNB to offer the reader a complete picture about the evolution of this technique over the last decades.

Recent management of endometrial cancer: a narrative review of the literature

Endometrial cancer is a common female gynecological neoplasia and its incidence rate has increased in the past years. Due to its predominant symptoms, most women will present uterine bleeding. It is usually diagnosed at an early stage and surgery has an important role in the treatment plan. The prognosis and quality of life of these patients can be quite favorable, if proper treatment is offered by surgeons. Traditionally, more invasive approaches and procedures were offered to these patients, but recent data suggest that more conservative and minimal invasive choices can be adopted in the treatment algorithm. Minimal invasive surgery, such as laparoscopy and robotic surgery, should be considered as an acceptable alternative, compared to laparotomy with less comorbidities and similar oncological and survival outcomes. Furthermore, sentinel lymph node biopsy has emerged in the surgical staging of endometrial cancer, in order to replace comprehensive lymphadenectomy. It is associated with less intra- and postoperative complications, while preliminary data show no difference in survival rates. However, sentinel lymph node biopsy should be offered within a strict algorithm, to avoid residual metastatic disease. The aim of this review is to analyze all the available data for the application of minimal invasive surgery in early endometrial cancer and especially the role of sentinel lymph node biopsy.

Detection and dissection of sentinel nodes in endometrial endometrioid cancer with indocyanine green using PinPoint laparoscopy: Analysis of the learning curve

OBJECTIVE

Early-stage endometrial endometrioid adenocarcinoma is managed through laparoscopic total hysterectomy with bilateral salpingo-oophorectomy and pelvic lymphadenectomy. Detection of positive nodes is rare, and lymphadenectomy may involve complications. Pelvic sentinel lymph node dissection can prevent complete dissection. Herein, we evaluated the learning curve of sentinel lymph node dissection using indocyanine green.

STUDY DESIGN

All surgeries for endometrial endometrioid adenocarcinoma were performed laparoscopically with indocyanine green to detect sentinel nodes. The primary outcome was the ability to identify and resect sentinel lymph nodes on each side. The secondary outcome was correspondence between the frozen section histology of the nodes with the final histology.

RESULTS

Among 31 patients with endometrial endometrioid adenocarcinoma treated between October 2018 and August 2020, 29 who underwent laparoscopy using indocyanine green were enrolled. Complete lymphadenectomy was performed in 16 patients. Failure to recognize sentinel nodes on right and left sides occurred in 10.34% and 0% of cases, respectively. The median number of recognized and dissected sentinel nodes was 1 on both sides (range 0-5). One patient had a lymph node positive for malignancy on histology (3.45%) on both sides. There were 13 and 14 cases of negative frozen sections on the right and left sides, respectively, and 1 case of a positive frozen section with positive whole pelvic lymph nodes.

CONCLUSION

Sentinel node dissection using indocyanine green in endometrial endometrioid adenocarcinoma has a distinct learning curve; however, it is practical and achievable for skilled surgeons.

Sentinel lymph node sampling versus full lymphadenectomy in endometrial cancer: a SEER database analysis

OBJECTIVE

To assess the long term outcomes and prognosis of sentinel lymph node sampling compared with full lymph node dissection in endometrial cancer patients.

METHODS

We used the Surveillance, Epidemiology, and End Results (SEER) database for information on women diagnosed with endometrial cancer from 2010 to 2019. We conducted a comparison including overall survival between patients who had undergone sentinel lymph node sampling only and patients who had undergone formal lymph node dissection. Propensity score matching was performed according to the patient's age, type of endometrial cancer, grade and stage of disease, and adjuvant therapy. Subgroup analyses were performed according to type and grade of endometrial cancer.

RESULTS

41411 endometrial cancer patients were identified through the database. After matching, 6019 patients each were included in the sentinel lymph node and lymph node dissection groups. Median (interquartile range (IQR)) follow-up time was 16 (7-31) months in both groups. One year survival rates were longer in the sentinel lymph node group compared with the lymph node dissection group (hazard ratio (HR) 1.61 (95% confidence interval (CI) 1.17 to 2.21); p=0.004). Subgroups analysis according to grade of disease showed that 1 year survival rates were longer in the sentinel lymph node group in patients with endometrioid-type grade 1-2 endometrial cancer (HR 1.70 (95% CI 1.31 to 2.56); p=0.01), while no difference in survival was found between the sentinel lymph node and lymph node dissection groups in the subgroup of patients with high grade endometrial cancer (HR 1.40 (95%CI 0.94 to 2.24); p=0.17). In patients with low grade endometrial cancer included in the sentinel lymph node group, only 7% had lymph nodes positive for malignancy compared with 17% in the high grade group.

CONCLUSION

Survival rates were not compromised in endometrial cancer patients undergoing sentinel lymph node sampling versus full lymph node dissection for all grades of disease.

Intraoperative Utilization of Indocyanine Green (ICG) Dye for the Assessment of Ovarian Perfusion-Case Report and Review of the Literature

The assessment of ovarian perfusion after detorsion is crucial in the surgical management of patients with ovarian torsion. In current routine clinical practice, the surgical decision (preservation of the ovary versus oophorectomy) is based on the subjective impression of the surgeon. Intraoperative indocyanine green (ICG) angiography has been shown to sufficiently reflect tissue perfusion with a potential impact on the surgical procedure. Currently, there are only sparse data available on the utilization of ICG in the surgical treatment of ovarian torsion. Here, we describe the successful intraoperative use of ICG in a 17-year-old female patient with ovarian torsion who underwent ovary-preserving surgery. Further, a systematic literature review was performed. Based on the data available to date, the use of ICG in the surgical treatment of ovarian torsion is feasible and safe. The extent to which this might reduce the necessity for oophorectomy has to be evaluated in further investigations.

Lymphatic Complications Following Sentinel Node Biopsy or Pelvic Lymphadenectomy for Endometrial Cancer

Sentinel node biopsy (SNB) is performed worldwide in patients with endometrial cancer (EC). The aim of this study was to evaluate and compare the occurrence rate of lymphatic complications between SNB and pelvic lymphadenectomy (LND) for EC. The medical records of women who underwent SNB or pelvic LND for EC between September 2012 and April 2022 were assessed. A total of 388 patients were enrolled in the current study. Among them, 201 patients underwent SNB and 187 patients underwent pelvic LND. The occurrence rates of lower-extremity lymphedema (LEL) and pelvic lymphocele (PL) were compared between the patients who underwent SNB and those who underwent pelvic LND. The SNB group had a significantly lower occurrence rate of lower-extremity LEL than the pelvic LND group (2.0% vs. 21.3%, p < 0.01). There were no patients who had PL in the SNB group; however, 4 (2.1%) patients in the pelvic LND group had PL. The occurrence rates of lower-extremity LEL and PL were significantly lower in patients who underwent SNB than those who underwent pelvic LND. SNB for EC has a lower risk of lymphatic complications compared to systemic LND.

The Premetastatic Lymph Node Niche in Gynecologic Cancer

It has been suggested that a primary tumor can "prepare" the draining of lymph nodes to "better accommodate" future metastatic cells, thus implying the presence of a premetastatic lymph node niche. However, this phenomenon remains unclear in gynecological cancers. The aim of this study was to evaluate lymph-node draining in gynecological cancers for premetastatic niche factors, such as myeloid-derived suppressor cells (MDSCs), immunosuppressive macrophages, cytotoxic T cells, immuno-modulatory molecules, and factors of the extracellular matrix. This is a monocentric retrospective study of patients who underwent lymph-node excision during their gynecological-cancer treatment. In all, 63 non-metastatic pelvic or inguinal lymph nodes, 25 non-metastatic para-aortic lymph nodes, 13 metastatic lymph nodes, and 21 non-cancer-associated lymph nodes (normal controls) were compared for the immunohistochemical presence of CD8 cytotoxic T cells, CD163 M2 macrophages, S100A8/A9 MDSCs, PD-L1+ immune cells, and tenascin-C, which is a matrix remodeling factor. PD-L1-positive immune cells were significantly higher in the control group, in comparison to the regional and distant cancer-draining lymph nodes. Tenascin-C was higher in metastatic lymph nodes than in both non-metastatic nodes and control lymph nodes. Vulvar cancer-draining lymph nodes showed higher PD-L1 values than endometrial cancer and cervical cancer-draining lymph nodes. Endometrial cancer-draining nodes had higher CD163 values and lower CD8 values, compared to vulvar cancer-draining nodes. Regarding regional draining nodes in low- and high-grade endometrial tumors, the former showed lower S100A8/A9 and CD163 values. Gynecological cancer-draining lymph nodes are generally immunocompetent, but vulvar cancer draining nodes, as well as high-grade endometrial cancer draining nodes, are more susceptible to harboring premetastatic niche factors.

Uterine Neoplasms, Version 1.2023, NCCN Clinical Practice Guidelines in Oncology

Adenocarcinoma of the endometrium (also known as endometrial cancer, or more broadly as uterine cancer or carcinoma of the uterine corpus) is the most common malignancy of the female genital tract in the United States. It is estimated that 65,950 new uterine cancer cases will have occurred in 2022, with 12,550 deaths resulting from the disease. Endometrial carcinoma includes pure endometrioid cancer and carcinomas with high-risk endometrial histology (including uterine serous carcinoma, clear cell carcinoma, carcinosarcoma [also known as malignant mixed Müllerian tumor], and undifferentiated/dedifferentiated carcinoma). Stromal or mesenchymal sarcomas are uncommon subtypes accounting for approximately 3% of all uterine cancers. This selection from the NCCN Guidelines for Uterine Neoplasms focuses on the diagnosis, staging, and management of pure endometrioid carcinoma. The complete version of the NCCN Guidelines for Uterine Neoplasms is available online at NCCN.org.

Technetium Tc 99m tilmanocept fails to detect sentinel lymph nodes in endometrial cancer

•

Indocyanine green (ICG) is effective for sentinel lymph node detection (SLN) in endometrial cancer.

•

Technetium Tc 99m tilmanocept is FDA-approved for SLN detection in breast cancer, melanoma, and head and neck cancers.

•

We aimed to determine the SLN detection rate in endometrial cancer with concurrent technetium Tc 99m tilmanocept and ICG use.

•

Technetium Tc 99m tilmanocept failed to detect sentinel lymph nodes in endometrial cancer patients in our prospective study.

•

ICG alone remains a standard SLN detection technique in endometrial cancer, while limiting burdens from a dual agent.

Background

Technetium Tc 99m tilmanocept is a synthetic radiotracer specifically designed for sentinel lymph node (SLN) mapping that has been FDA-approved in breast cancer, melanoma, and head and neck cancer. No published studies exist for the use of this radiotracer in endometrial cancer.

Objective

The primary objective was to determine the detection rate of bilateral SLNs in endometrial cancer with the concurrent use of technetium Tc 99m tilmanocept and ICG.

Methods

An open-label, single cohort, prospective feasibility study was conducted with participants receiving preoperative cervical injections of technetium Tc 99m tilmanocept followed by subsequent imaging and SPECT/CT. Intraoperative ICG injections were administered for all patients with near-infrared imaging used to visualize lymphatic vessels and nodes. A laparoscopic gamma counter was used to detect radioactive SLN intraoperatively.

Results

All six evaluated patients had FIGO grade 1 or 2 endometrioid histology. Stage IA/IB were in 33% and 66% of patients, respectively. Tilmanocept did not map any SLN in the first six patients but instead showed retention of the tracer in the cervical stroma, leading to study discontinuation for futility. ICG mapped bilateral SLN in all patients with the most common location being the external iliac region, followed by the obturator and common iliac areas. All patients had CD206 positive staining throughout the full wall thickness of ectocervix, transformation zone, endocervix, and lymphatic vessels. No patients experienced adverse events.

Conclusion

Technetium Tc 99m tilmanocept did not detect SLN in early stage endometrial cancers and is unlikely to improve bilateral detection rate compared to ICG alone. ICG remains a standard technique for SLN detection in low stage, low grade endometrial cancer.

The Role of Sentinel Lymph Node Mapping in High-grade Endometrial Cancer

OPINION STATEMENT

Total hysterectomy with lymph node assessment is the current standard-of-care for surgical staging in apparent early-stage endometrial cancer. Compared to the traditional complete pelvic lymphadenectomy with or without para-aortic lymphadenectomy, sentinel lymph node (SLN) mapping results in fewer surgical complications, decreased operative time, and lower rates of chronic lymphedema. The technique is endorsed by the National Comprehensive Cancer Network and the Society of Gynecologic Oncology guidelines, and over the past two decades the majority of gynecologic oncologists worldwide have adopted SLN mapping into their practice. However, as the results of the initial SLN studies were mostly based on low-grade tumors, adoption of the technique in high-grade tumors has been slower and more controversial. In this review, we discuss the most recent studies evaluating the SLN mapping in high-grade endometrial cancers. The results of these studies suggest that the SLN detection rate is acceptably high and the negative predictive value is sufficiently low to support the use of SLN mapping in high-grade endometrial tumors to replace complete lymphadenectomy. Validity of SLN mapping techniques does, however, require following a standard algorithm, and success depends also on surgeon expertise. Moreover, the impact of SLN mapping on overall survival in high-grade tumors requires future prospective randomized studies. Finally, a transition toward near-universal SLN mapping techniques for endometrial cancers could significantly impact on the adequacy of gynecologic oncology fellows' surgical training and competency in lymphadenectomy.

Feasibility of Sentinel Lymph Node Sampling in Early-Stage Carcinoma Endometrium: Single-Institution Experience

Introduction

Accurate surgical staging is an essential component in the management of carcinoma endometrium to assess the stage of disease and to tailor adjuvant treatment. Sentinel node technique was introduced as an alternative for extensive lymphadenectomy in early stages to avoid complications associated with lymphadenectomy.

Aims and Objectives

To assess the detection rate and diagnostic accuracy of SLN mapping in patients with early-stage carcinoma endometrium.

Materials and Methods

Prospective validation study involving 30 patients diagnosed to have early-stage carcinoma endometrium. Sentinel nodes were detected by combined methods of radio colloid dye and isosulphan blue dye injection.

Results

Sentinel lymph node was detected in 19 patients (63.4%). 11 patients had no sentinel nodes. Total number of sentinel nodes isolated was 68 with a mean of 2.26 per patient (range 0-4). Ten (33.33%) patients had single sentinel node location, while 9 (30%) had more than 1 sentinel lymph nodes. Twelve patients had bilateral sentinel nodes, and the most frequent location of sentinel node was obturator, 19 (63.3%) especially on right hemi-pelvis. One patient had a hot para-aortic node, while none had blue para-aortic sentinel node. Average number of lymph nodes obtained by lymphadenectomy was 13 per patient (range 7-22). All patients with sentinel node had negative frozen report as well as in histopathology. Two patients in whom no sentinel nodes were detected by either techniques had metastatic nodes in histopathology report.

Conclusion

Detection rate was maximum with radiocolloid dye, and it is better to utilize the technique for less graded tumours and endometrioid variants.

A large multicenter propensity match study of sentinel lymph node biopsy feasibility in endometrioid variants of endometrial cancer

INTRODUCTION

Sentinel lymph node (SLN) biopsy algorithm has been routinely applied in all endometrial endometrioid tumors, however, no studies analyzed the feasibility of SLN mapping in endometrioid variants (EV), which included villoglandular, secretory, ciliated cell, mucinous, and squamous differentiation. This study aimed to demonstrate the feasibility of SLN biopsy in EV of EC.

MATERIALS AND METHODS

All patients undergoing minimally invasive surgical treatment for early-stage EC were included in the study. Patients were divided into 2 study groups: Group 1 which included patients with EV, and Group 2 which included patients with typical endometrioid histology. A propensity match analysis was performed according to age (≥65 years vs. no), BMI (≥30 kg/m² vs. no), and LVSI (present vs. absent).

RESULTS

After a 1:5 propensity-matched analysis, a total of 458 patients were identified (Group 1 n = 77, Group 2 n = 381). Overall detection rate was not statistically significant between the EV and the typical endometrioid group (94.8% vs. 92.4%, p = 0.319). Furthermore, neither bilateral nor unilateral detection rate was different between the two groups (70.1% vs. 74.8%, p = 0.267, and 23.4% vs. 17.8%, p = 0.120). BMI ≥30 kg/m² was the only factor influencing SLN failure (p = 0.013). SLN technique showed excellent sensitivity in both the EV (100% sensitivity, p < 0.001) and the typical endometrioid unit (93.8% sensitivity, p < 0.001).

CONCLUSION

SLN research/detection for EV of endometrial cancer is a feasible and highly sensitive technique. Obesity was confirmed to be a risk factor for SLN failure.

Quantitative and Semi-quantitative Methods for Assessing the Degree of Methylene Blue Staining in Sentinel Lymph Nodes in Dogs

Background: To develop a digital algorithm for quantitative assessment of surface methylene blue staining in whole lymph nodes and validate a semi-quantitative visual scoring method for patient-side use.

Methods: Lymph nodes from canine patients with spontaneous tumors undergoing sentinel lymph node mapping were prospectively assessed ex vivo and photographed. Using an open-source computer-based imaging software, an algorithm was developed for quantification of staining based on a signal-to-background ratio. Next, two blinded observers evaluated images and assigned a semi-quantitative visual score based on surface staining (0—no blue stain, 1−1–50% stained, and 2−51–100% stained) and those results were compared to the established quantitative standard.

Results: Forty-three lymph nodes were included. Image analysis successfully quantified blue staining and differentiated from normal lymph node tissue in all cases. Agreement between observers using the Kappa coefficient demonstrated strong agreement (k = 0.8581, p < 0.0001) between semi-quantitative visual scoring and image analysis. There was substantial interobserver and intraobserver agreement for the scoring system (k = 0.7340, p < 0.0001 and k = 0.8983, p < 0.0001, respectively).

Conclusion: A digital algorithm using an open-source software was simple and straightforward to use for quantification of blue staining. The use of a semi-quantitative visual scoring system shows promise for a simple, objective, repeatable assessment of methylene blue staining at the time of surgery. This study demonstrates reliable and repeatable methods for blue staining quantification thereby providing a novel and objective reporting mechanism in scientific research involving sentinel lymph node mapping.

Sentinel Lymph Node Sampling in Robot-Assisted Staging of Endometrial Cancer

OBJECTIVE

Sentinel lymph node (SLN) sampling in endometrial cancer staging has become an acceptable standard. Indocyanine green dye injected into the cervix and detected by near-infrared light is technically simple and sensitive. We aimed to evaluate SLN sampling in robot-assisted surgical staging of endometrial cancer at a university-affiliated teaching hospital.

METHODS

A retrospective chart review, from January 2016 to December 2017, of patients who underwent robot-assisted surgical staging with cervical injection of indocyanine green dye detected by near-infrared light. The map rate, sensitivity, false negatives, and negative predictive value were calculated.

RESULTS

A total of 105 charts were reviewed; 79 patients met inclusion criteria. The mean age was 65 (range 38-93) and the mean body mass index was 33.3 (range 16-49). Most patients (72.2%) had stage I disease and grade 1 or 2 histology (77.1%). Eight (10.1%) patients had lymph node metastasis. Seventy-two (91.1%) patients had positive mapping to at least 1 SLN. Sixty-two (78.5%) patients had bilateral mapping. Forty-four patients had concurrent pelvic ± para-aortic lymph node dissection and were included in the sensitivity analysis. Five of 44 cases had LN metastasis. The sensitivity was 80%, and the negative predictive value of SLN sampling was 97.5%.

CONCLUSIONS

SLN mapping and sampling at a university-affiliated teaching hospital have comparable map rate, sensitivity, and negative predictive value as demonstrated in multiple trials. The technique has the potential to standardize endometrial cancer staging across different practice settings.

Sentinel Lymph Nodes and Precision Surgery in Gynecologic Cancer

Besides histologic features, the presence of nodal metastasis is the most crucial prognostic factor for recurrence and survival for patients with gynecologic cancer. Conventionally, lymphadenectomy has been performed routinely to assess lymphatic metastasis. However, lymphadenectomy may be unnecessary in early-stage gynecologic cancer, because the percentage of patients with lymph node involvement is very low. The recent use of sentinel lymph node mapping has provided high feasibility, safety, and accuracy in the assessment of nodal metastasis. The National Comprehensive Cancer Network Clinical Practice Guidelines have incorporated the sentinel lymph node for nodal evaluation in vulvar, endometrial, and cervical cancers.

Sentinel node biopsy for diagnosis of lymph node involvement in endometrial cancer

BACKGROUND

Pelvic lymphadenectomy provides prognostic information for those diagnosed with endometrial (womb) cancer and provides information that may influence decisions regarding adjuvant treatment. However, studies have not shown a therapeutic benefit, and lymphadenectomy causes significant morbidity. The technique of sentinel lymph node biopsy (SLNB), allows the first draining node from a cancer to be identified and examined histologically for involvement with cancer cells. SLNB is commonly used in other cancers, including breast and vulval cancer. Different tracers, including colloid labelled with radioactive technetium-99, blue dyes, e.g. patent or methylene blue, and near infra-red fluorescent dyes, e.g. indocyanine green (ICG), have been used singly or in combination for detection of sentinel lymph nodes (SLN).

OBJECTIVES

To assess the diagnostic accuracy of sentinel lymph node biopsy (SLNB) in the identification of pelvic lymph node involvement in women with endometrial cancer, presumed to be at an early stage prior to surgery, including consideration of the detection rate.

SEARCH METHODS

We searched MEDLINE (1946 to July 2019), Embase (1974 to July 2019) and the relevant Cochrane trial registers.

SELECTION CRITERIA

We included studies that evaluated the diagnostic accuracy of tracers for SLN assessment (involving the identification of a SLN plus histological examination) against a reference standard of histological examination of removed pelvic +/- para-aortic lymph nodes following systematic pelvic +/- para-aortic lymphadenectomy (PLND/PPALND) in women with endometrial cancer, where there were sufficient data for the construction of two-by-two tables.

DATA COLLECTION AND ANALYSIS

Two review authors (a combination of HN, JM, NW, RG, and WH) independently screened titles and abstracts for relevance, classified studies for inclusion/exclusion and extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We calculated the detection rate as the arithmetic mean of the total number of SLNs detected out of the total number of women included in the included studies with the woman as the unit of analysis, used univariate meta-analytical methods to estimate pooled sensitivity estimates, and summarised the results using GRADE.

MAIN RESULTS

The search revealed 6259 unique records after removal of duplicates. After screening 232 studies in full text, we found 73 potentially includable records (for 52 studies), although we were only able to extract 2x2 table data for 33 studies, including 2237 women (46 records) for inclusion in the review, despite writing to trial authors for additional information. We found 11 studies that analysed results for blue dye alone, four studies for technetium-99m alone, 12 studies that used a combination of blue dye and technetium-99m, nine studies that used indocyanine green (ICG) and near infra-red immunofluorescence, and one study that used a combination of ICG and technetium-99m. Overall, the methodological reporting in most of the studies was poor, which resulted in a very large proportion of 'unclear risk of bias' ratings. Overall, the mean SLN detection rate was 86.9% (95% CI 82.9% to 90.8%; 2237 women; 33 studies; moderate-certainty evidence). In studies that reported bilateral detection the mean rate was 65.4% (95% CI 57.8% to 73.0%) . When considered according to which tracer was used, the SLN detection rate ranged from 77.8% (95% CI 70.0% to 85.6%) for blue dye alone (559 women; 11 studies; low-certainty evidence) to 100% for ICG and technetium-99m (32 women; 1 study; very low-certainty evidence). The rates of positive lymph nodes ranged from 5.2% to 34.4% with a mean of 20.1% (95% CI 17.7% to 22.3%). The pooled sensitivity of SLNB was 91.8% (95% CI 86.5% to 95.1%; total 2237 women, of whom 409 had SLN involvement; moderate-certainty evidence). The sensitivity for of SLNB for the different tracers were: blue dye alone 95.2% (95% CI 77.2% to 99.2%; 559 women; 11 studies; low-certainty evidence); Technetium-99m alone 90.5% (95% CI 67.7% to 97.7%; 257 women; 4 studies; low-certainty evidence); technetium-99m and blue dye 91.9% (95% CI 74.4% to 97.8%; 548 women; 12 studies; low-certainty evidence); ICG alone 92.5% (95% CI 81.8% to 97.1%; 953 women; 9 studies; moderate-certainty evidence); ICG and blue dye 90.5% (95% CI 63.2.6% to 98.1%; 215 women; 2 studies; low-certainty evidence); and ICG and technetium-99m 100% (95% CI 63% to 100%; 32 women; 1 study; very low-certainty evidence). Meta-regression analyses found that the sensitivities did not differ between the different tracers used, between studies with a majority of women with FIGO stage 1A versus 1B or above; between studies assessing the pelvic lymph node basin alone versus the pelvic and para-aortic lymph node basin; or between studies that used subserosal alone versus subserosal and cervical injection. It should be noted that a false-positive result cannot occur, as the histological examination of the SLN is unchanged by the results from any additional nodes removed at systematic lymphadenectomy.

AUTHORS' CONCLUSIONS

The diagnostic test accuracy for SLNB using either ICG alone or a combination of a dye (blue or ICG) and technetium-99m is probably good, with high sensitivity, where a SLN could be detected. Detection rates with ICG or a combination of dye (ICG or blue) and technetium-99m may be higher. The value of a SLNB approach in a treatment pathway, over adjuvant treatment decisions based on uterine factors and molecular profiling, requires examination in a high-quality intervention study.

Status of Sentinel Lymph Node Biopsy in Endometrial Cancer

The role of lymphadenectomy in surgical staging remains one of the biggest controversies in the management of endometrial cancer. The concept of sentinel lymph node biopsy in endometrial cancer has been evaluated for a number of years, with promising sensitivity rates and negative predictive values. The possibility of adequate staging while avoiding systematic lymphadenectomy leads to a significant reduction in the rate of peri- and postoperative morbidity. Nevertheless, the status of sentinel lymph node biopsy in endometrial cancer has not yet been fully elucidated and is variously assessed internationally. According to current European guidelines and recommendations, sentinel lymph node biopsy in endometrial cancer should be performed only in the context of clinical studies. In this review article, the developments of the past decade are explored concisely. In addition, current data regarding the technical aspects, accuracy and prognostic relevance of sentinel lymph node biopsy are explained and evaluated critically.

Comparison of SPECT-CT with intraoperative mapping in cervical and uterine malignancies

INTRODUCTION

The objective was to evaluate whether hybrid imaging combining single photon emission tomography with computed tomography (SPECT/CT) provides additional clinical value for dectection of sentinel lymph nodes (SLNs) compared with intraoperative combined mapping in uterine and cervical malignancies.

METHODS

This was a retrospective study of prospectively collected data from patients with stages IA-IB2 cervical cancer (International Federation of Gynecology and Obstetrics (FIGO) 2018) or stage I endometrial cancer, who underwent preoperative SPECT/CT for SLN detection. All included patients had dual injection of technetium-99m (99mTc) with patent blue or indocyanine green.

RESULTS

A total of 171 patients were included with 468 SLNs detected during surgery: 146/171 patients (85.4%) had both radiotracer and blue injection whereas 25/171 patients (14.6%) had radiotracer and indocyanine green injected. The overall detection rate was 95.3%. The detection rate of SLN mapping was 74.9% for SPECT/CT, 90.6% for 99mTc, 91.8% for blue dye, and 100% for indocyanine green. Bilateral drainage was found in 140 patients (81.9%), detected by 99mTc in 105 patients (61.4%), by blue in 99 patients (67.3%), by indocyanine green in 23 patients (92%), and by SPECT/CT in 62 patients (36.4%). Atypical SLN locations were identified by SPECT/CT in 64 patients (37.4%), by 99mTc in 28 patients (16.4%), by blue in 17 patients (9.9%), and by indocyanine green in 8 patients (4.7%). Sensitivity and negative predictive value of SLN biopsy to detect lymph node metastasis using dual injection of different intraoperative combined techniques were 88.9% and 97.5%, respectively.

CONCLUSION

SPECT/CT enhanced topographic delineation of SLN and more accurately identified drainage to atypical locations. Fluorescent SLN mapping using indocyanine green offered the highest SLN detection rate. When indocyanine green was used, SPECT/CT did not increase SLN detection, and did not add further information to improve lymph node localization and removal.

Ultrastaging methods of sentinel lymph nodes in endometrial cancer - a systematic review

OBJECTIVE

Sentinel lymph node mapping has emerged as an alternative to lymphadenectomy in evaluating the lymph node status in endometrial cancer. Several pathological methods to examine the sentinel lymph node are applied internationally. The aim of this study was to determine the value of ultrastaging and to assess the ultrastaging method with the highest detection rate of metastases.

METHODS

A systematic review was conducted. Inclusion criteria were: pathologically-confirmed endometrial cancer with sentinel lymph node mapping, report of the histological outcomes, metastases found by hematoxylin and eosin staining and metastases found by ultrastaging were separately mentioned, and description of the ultrastaging method. The primary outcome was the detection of metastases found by ultrastaging that were not detected by routine hematoxylin and eosin staining. The secondary outcome was the difference in detection rate of metastases between several ultrastaging methods. Random effects meta-analyses were conducted.

RESULTS

Fifteen studies were selected, including 2259 patients. Sentinel lymph nodes were examined by routine hematoxylin and eosin staining. Subsequently, multiple ultrastaging methods were used, with differences in macroscopic slicing (bread-loaf/longitudinal), number of microscopic slides, and distance between slides, but all used immunohistochemistry. A positive sentinel lymph node was found in 14% of patients. In 37% of these, this was detected only by ultrastaging. Using more ultrastaging slides did not result in a higher detection rate. Bread-loaf slicing led to a higher detection rate compared with longitudinal slicing (mean detection rates 53% and 33%, respectively).

CONCLUSION

Pathological ultrastaging after routine hematoxylin and eosin staining in endometrial cancer patients has led to an increased detection rate of sentinel lymph node metastases. Different ultrastaging methods are used, with a preference for bread-loaf slicing. However, due to the large heterogeneity of the studies, assessing which ultrastaging method has the highest detection rate of sentinel lymph node metastases was not possible.

Development of a surgical competency assessment tool for sentinel lymph node dissection by minimally invasive surgery for endometrial cancer

INTRODUCTION

Sentinel lymph node dissection is widely used in the staging of endometrial cancer. Variation in surgical techniques potentially impacts diagnostic accuracy and oncologic outcomes, and poses barriers to the comparison of outcomes across institutions or clinical trial sites. Standardization of surgical technique and surgical quality assessment tools are critical to the conduct of clinical trials. By identifying mandatory and prohibited steps of sentinel lymph node (SLN) dissection in endometrial cancer, the purpose of this study was to develop and validate a competency assessment tool for use in surgical quality assurance.

METHODS

A Delphi methodology was applied, included 35 expert gynecological oncology surgeons from 16 countries. Interviews identified key steps and tasks which were rated mandatory, optional, or prohibited using questionnaires. Using the surgical steps for which consensus was achieved, a competency assessment tool was developed and subjected to assessments of validity and reliability.

RESULTS

Seventy percent consensus agreement standardized the specific mandatory, optional, and prohibited steps of SLN dissection for endometrial cancer and informed the development of a competency assessment tool. Consensus agreement identified 21 mandatory and three prohibited steps to complete a SLN dissection. The competency assessment tool was used to rate surgical quality in three preselected videos, demonstrating clear separation in the rating of the skill level displayed with mean skills summary scores differing significantly between the three videos (F score=89.4; P<0.001). Internal consistency of the items was high (Cronbach α=0.88).

CONCLUSION

Specific mandatory and prohibited steps of SLN dissection in endometrial cancer have been identified and validated based on consensus among a large number of international experts. A competency assessment tool is now available and can be used for surgeon selection in clinical trials and for ongoing, prospective quality assurance in routine clinical care.

Surgical complications occurring during minimally invasive sentinel lymph node detection in endometrial cancer patients. A systematic review of the literature and metanalysis

INTRODUCTION

Endometrial cancer (EC) is the most common gynecological cancer. Sentinel lymph node (SLN) technique has been adopted worldwide and showed lower morbidity and superimposable survival outcomes than the systematic lymphadenectomy (LND). Although these encouraging results, no meta-analyzes were performed on surgical complications during SLN research among patients undergoing laparoscopic (L) versus robotic surgery (R). The present review aims to report surgical complications during laparoscopic versus robotic SLN technique.

METHODS

The Preferred Reporting Items for Systematic reviews and Meta-Analyzes (PRISMA) and the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines have been followed for the present meta-analysis.

RESULTS

Six studies, including 769 participants, were included. L-LND resulted in a significantly higher risk of operative complications relative to L-SLN (RR 2.10 [95% CI 1.37 to 3.21]). The risk of complications was comparable between R-SLN and L-SLN (RR 2.32 [95% CI 0.04-121.02]) and between R-LND and L-LND (RR 2.17 [95% CI 0.04-126.69]). According to the SUCRA analysis, L-SLN and R-SLN had the highest chances of being ranked first among proposed surgical procedures (SUCRA 48.9% and 28.4% respectively).

CONCLUSIONS

Our study reported a lower surgical complications rate in patients undergoing L-SLN technique compared to L-LND. A lower rate of surgical complications was also reported for the R-SLN technique compared to the R-LND. Both laparoscopic and robotic SLN surgical techniques were found to be safe surgical procedures.

Sentinel node mapping using indocyanine green and near-infrared fluorescence imaging technology for endometrial cancer: A prospective study using a surgical algorithm in Indian patients

Background:

Indocyanine green (ICG) fluorescence with high-definition, three-dimensional imaging systems is emerging as the latest strategy to reduce trauma and improve surgical outcomes during oncosurgery.

Materials and Methods:

This is a prospective study involving 100 patients with carcinoma endometrium who underwent robotic-assisted Type 1 pan-hysterectomy, with ICG-directed sentinel lymph node (SLN) biopsy from November 2017 to December 2019. The aim was to assess the feasibility and diagnostic accuracy of SLN algorithm and to evaluate the location and distribution of SLN in pelvic, para-aortic and unusual areas and the role of frozen section.

Results:

The overall SLN detection rate was 98%. Bilateral detection was possible in 92% of the cases. Right side was detected in 98% of the cases and left side was visualised in 92% of the cases. Complete node dissection was done where SLN mapping failed. The most common location for SLN in our series was obturator on the right hemipelvis and internal iliac on the left hemipelvis. SLN in the para-aortic area was detected in 14% of cases. In six cases, SLN was found in atypical locations, that is pre-sacral area. Eight patients had SLN positivity for metastasis and underwent complete retroperitoneal lymphadenectomy. Comparison of final histopathological report with frozen section reports showed no false negatives.

Conclusions:

SLN mapping holds a great promise as a modern staging strategy for endometrial cancer. In our experience, cervical injection was an optimal method of mapping the pelvis. 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. The ICG fluorescence imaging system is simple and safe and may become a standard in oncosurgery in view of its staging and anatomical imaging capabilities. This approach can reduce the morbidity, operative times and costs associated with complete lymphadenectomy while maintaining prognostic and predictive information.

Operative and Oncological Outcomes Comparing Sentinel Node Mapping and Systematic Lymphadenectomy in Endometrial Cancer Staging: Meta-Analysis With Trial Sequential Analysis

Objective

To evaluate the utility of sentinel lymph node mapping (SLN) in endometrial cancer (EC) patients in comparison with lymphadenectomy (LND).

Methods

Comprehensive search was performed in MEDLINE, EMBASE, CENTRAL, OVID, Web of science databases, and three clinical trials registration websites, from the database inception to September 2020. The primary outcomes covered operative outcomes, nodal assessment, and oncological outcomes. Software Revman 5.3 was used. Trial sequential analysis (TSA) and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) were performed.

Results

Overall, 5,820 EC patients from 15 studies were pooled in the meta-analysis: SLN group (N = 2,152, 37.0%), LND group (N = 3,668, 63.0%). In meta-analysis of blood loss, SLN offered advantage over LND in reducing operation bleeding (I² = 74%, P<0.01). Z-curve of blood loss crossed trial sequential monitoring boundaries though did not reach TSA sample size. There was no difference between SLN and LND in intra-operative complications (I² = 7%, P = 0.12). SLN was superior to LND in detecting positive pelvic nodes (P-LN) (I² = 36%, P<0.001), even in high risk patients (I² = 36%, P = 0.001). While no difference was observed in detection of positive para-aortic nodes (PA-LN) (I² = 47%, P = 0.76), even in high risk patients (I² = 62%, P = 0.34). Analysis showed no difference between two groups in the number of resected pelvic nodes (I² = 99%, P = 0.26). SLN was not associated with a statistically significant overall survival (I² = 79%, P = 0.94). There was no difference in progression-free survival between SLN and LND (I² = 52%, P = 0.31). No difference was observed in recurrence. Based on the GRADE assessment, we considered the quality of current evidence to be moderate for P-LN biopsy, low for items like blood loss, PA-LN positive.

Conclusion

The present meta-analysis underlines that SLN is capable of reducing blood loss during operation in regardless of surgical approach with firm evidence from TSA. SLN mapping is more targeted for less node dissection and more detection of positive lymph nodes even in high risk patients with conclusive evidence from TSA. Utility of SLN yields no survival detriment in EC patients.

The role of sentinel lymph node mapping in endometrial carcinoma

Endometrial cancer is the most commonly diagnosed gynecological malignancy in developing countries, and the second malignancy after cervical cancer in developing countries. The primary treatment is based on surgical and pathologic staging including extrafascial type A radical hysterectomy bilateral salpingo-oophorectomy and pelvic and latero-aortic lymphadenectomy. Minimally invasive surgery is the most widely used technique. Sentinel node biopsy is part of this concept and has reached the management of endometrial cancer. The aim of this review was to describe the history, the different injection techniques and results of sentinel node biopsy, and analyze the future role of this technique in endometrial carcinoma.

Is the extent of pelvic lymphadenectomy in the staging of endometrial cancer associated with the yield of metastatic nodes? An Israeli Gynecologic Oncology Group study

OBJECTIVES

Primary, to explore correlation between the extent of pelvic lymphadenectomy in the surgical staging of endometrial cancer and the number of nodes with metastasis. Secondary, evaluate survival measures in relation to the number of excised nodes.

METHODS

A retrospective multi-center study of prospectively collected information of 2014 women with endometrial cancer, 1032 of whom underwent lymph node staging. Spearman's rank correlation was used to assess the correlation between the number of pelvic nodes excised and the number of metastatic nodes. Women's data were dichotomized by the median number of excised pelvic nodes. Kaplan-Meier and log rank tests were used to examine the effect of the number of pelvic nodes excised on survival.

RESULTS

There was no significant correlation between the number of pelvic nodes harvested and the number of metastatic lymph nodes (r = 0.301; p = 0.28). The median number of excised pelvic nodes was 9 (range 1-77). There was no difference between women with up to 9 and women with more than 9 lymph nodes excised in the 5-year recurrence-free survival (82.4% vs. 83.9%; p = 0.90), disease-specific survival (83.6% vs. 86.7%; p = 0.37), or overall survival (75.8% vs. 82.8%; p = 0.11).

CONCLUSIONS

The extent of pelvic lymphadenectomy in the surgical staging of endometrial cancer is not associated with a higher yield of metastatic nodes or with longer survival. Current focus should be on sentinel node procedures that offer women the benefit of accurate staging without the complications associated with extensive lymphadenectomy.

Gynaecological malignancies and sentinel lymph node mapping: an update

Assessment of pelvic, para-aortic or inguinal lymph nodes (LNs) provides not only important prognostic information, but also determines the need for adjuvant treatment. Sentinel lymph node (SLN) biopsy has the potential to provide this prognostic information, while reducing morbidity compared with extended LN dissection. This review discusses the clinical and pathological aspects of SLN biopsy in gynaecological cancer.

Evaluation of quality of life, body image and surgical outcomes of robotic total laparoscopic hysterectomy and sentinel lymph node mapping in low-risk endometrial cancer patients - A Robotic Gyne Club study

INTRODUCTION

The aims of the study were to evaluate quality of life, cosmetic results and surgical outcomes of robotic single-site and robotic multiport total laparoscopic hysterectomy with sentinel lymph node mapping in women treated for low-risk endometrial cancer.

MATERIAL AND METHODS

The study is a prospective, multicenter, case-control study conducted at Ospedale Santa Chiara in Trento and Novara and Pavia University Hospitals. Seventy-six consecutive patients with a biopsy-confirmed diagnosis of low-risk endometrial cancer or atypical endometrial hyperplasia who between January 2017 and January 2019 had undergone robotic total laparoscopic hysterectomy and sentinel lymph node mapping were included. Data on surgical outcomes, quality of life and cosmetic results were prospectively collected and analyzed based on the surgical approach with robotic single-site vs robotic multiport assistance. Patients' clinical characteristics, intra-operative parameters, sentinel lymph node mapping results and postoperative findings were prospectively recorded. Clinical follow up was performed 4 weeks and 6 and 12 months after surgery. Fifty-one patients underwent a robotic multiport procedure and 25 patients a robotic single-site surgery.

RESULTS

There was one significant difference between the two groups in terms of patient characteristics: mean body mass index (BMI) in the multiport group was 29 kg/m² vs 24.8 kg/m² in the single-site group (P value <.001). After univariate and multivariate analysis on intraoperative and postoperative findings, a shorter surgical time was observed in the single-site cohort than in the multiport group (148.7 vs 158.2 minutes, P value .0182). BMI also had a significant effect on surgical time (P = .022). No differences were seen in terms of sentinel lymph node detection: the bilateral detection rate was 96.1% for multiport (66.7% bilateral, 29.4% monolateral) and 96% for single-site (76% bilateral, 20% monolateral) procedures. No differences between the two approaches were identified with regard to postoperative complications, pain, cosmetic results or quality of life comparisons.

CONCLUSIONS

For the treatment of low-risk endometrial cancer and atypical endometrial hyperplasia with total hysterectomy and sentinel lymph node mapping, the robotic single-port approach is comparable to the multiport procedure in terms of intraoperative and postoperative findings, and has an advantage in terms of shorter surgical times. Further studies are required to identify possible differences in quality of life and cosmetic results.

Pelvic sentinel lymph node biopsy in endometrial cancer-a simplified algorithm based on histology and lymphatic anatomy

OBJECTIVE

To achieve the full potential of sentinel lymph node (SLN) detection in endometrial cancer, both presumed low- and high-risk groups should be included. Perioperative resource use and complications should be minimized. Knowledge on distribution and common anatomical sites for metastatic SLNs may contribute to optimizing the concept while maintaining sensitivity. Proceeding from previous studies, simplified algorithms based on histology and lymphatic anatomy are proposed.

METHODS

Data on mapping rates and locations of pelvic SLNs (metastatic and non-metastatic) from two previous prospective SLN studies in women with endometrial cancer were retrieved. Cervically injected indocyanine green was used as a tracer and an ipsilateral re-injection was performed in case of non-display of the upper and/or lower paracervical pathways. A systematic surgical algorithm was followed with clearly defined SLNs depicted on an anatomical chart. In high-risk endometrial cancer patients, removal of SLNs was followed by a pelvic and para-aortic lymphadenectomy.

RESULTS

423 study records were analyzed. The bilateral mapping rates of the upper and lower paracervical pathways were 88.9% and 39.7%, respectively. 72% of all SLNs were typically positioned along the upper paracervical pathway (interiliac and/or proximal obturator fossa) and 71 of 75 (94.6%) of pelvic node positive women had at least one metastatic SLN at either of these positions. Women with grade 1-2 endometroid cancers (n=275) had no isolated metastases along the lower paracervical pathway compared with two women with high-risk histologies (n=148).

CONCLUSION

SLNs along the upper paracervical pathway should be identified in all endometrial cancer histological subtypes; removal of nodes at defined typical positions along the upper paracervical pathway may replace a site-specific lymphadenectomy in case of non-mapping despite tracer re-injection. Detection of SLNs along the lower paracervical pathway can be restricted to high-risk histologies and a full pre-sacral lymphadenectomy should be performed in case of non-display.

Positron Lymphography via Intracervical 18F-FDG Injection for Presurgical Lymphatic Mapping in Cervical and Endometrial Malignancies

The presence of metastasis in local lymph nodes (LNs) is a key factor influencing choice of therapy and prognosis in cervical and endometrial cancers; therefore, the exploration of sentinel LNs (SLNs) is highly important. Currently, however, SLN mapping requires LN biopsy for pathologic evaluation, since there are no clinical imaging approaches that can identify tumor-positive LNs in early stages. Staging lymphadenectomy poses risks, such as leg lymphedema or lymphocyst formation. Furthermore, in 80%-90% of patients, the explored LNs are ultimately tumor-free, meaning most patients are unnecessarily subjected to lymphadenectomy. Methods: Current lymphoscintigraphy methods identify only the anatomic location of the SLNs and do not provide information on their tumor status. There are no noninvasive methods to reliably identify metastases in LNs before surgery. We have developed positron lymphography (PLG), a method to detect tumor-positive LNs, in which ¹⁸F-FDG is injected interstitially into the uterine cervix on the day of surgery, and its rapid transport through the lymphatic vessels to the SLN is then visualized with dynamic PET/CT. We previously showed that PLG was able to identify metastatic LNs in animal models. Here, we present the first results from our pilot clinical trial (clinical trials identifier NCT02285192) in 23 patients with uterine or cervical cancer. On the morning of surgery, ¹⁸F-FDG was injected into the cervix, followed by an immediate dynamic PET/CT scan of the pelvis and a delayed 1-h whole-body scan. Results: There were 3 (15%) node-positive cases on final pathologic analysis, and all of these LNs (including 1 with a focus of only 80 tumor cells) were identified by PLG. There were 2 (10%) false-positive cases with PLG, in which the final pathology of the corresponding SLNs was negative for tumor. Conclusion: This first-in-humans study of PLG in women with uterine and cervical cancer demonstrates its feasibility and its ability to identify patients with nodal metastases and warrants further evaluation in additional studies.

High risk endometrial cancer: Clues towards a revision of the therapeutic paradigm

INTRODUCTION

Endometrial cancer (EC) is a major cause of mortality worldwide with nearly 200 000 cases diagnosed annually. The recent ESMO-ESGO-ESTRO guidelines include a new classification defining a heterogeneous high-risk group of recurrence (HR) comprising: (i) endometrioid (type 1) FIGO stage IB grade 3 tumors (type 1/G3ECs), (ii) non-endometrioid tumors (type 2) and (iii) advanced stages whatever the histological type (Colombo et al., 2016).

AREAS COVERED

The aim of this review is to summarize current evidence for therapeutic approaches in HR-EC according to the updated ESMO-ESGO-ESTRO classification by discussing the following issues: i) HR-EC heterogeneity, (ii) prognostic factors and current classification, and (iii) optimal staging strategies (site and extent) and the role of adjuvant treatment.

EXPERT COMMENTARY

HR-EC treatment is based on surgery, radiation therapy, brachytherapy, and chemotherapy, either alone or sequentially, in combination with other treatments depending on disease stage, histological grade and risk group. Specific trials are needed to establish the role of systematic pelvic and paraaortic lymphadenectomy, adjuvant therapies and targeted drugs. Although molecular characterization has been reported to customize therapeutic strategies and thereby improve therapeutic outcomes in EC, none of the targeted agents investigated (antiangiogenic and mTOR/PI3K pathway inhibitor agents) have resulted in a change in clinical practice in HR-EC.

Sentinel Lymph Node Ultra-staging as a Supplement for Endometrial Cancer Intraoperative Frozen Section Deficiencies

For endometrial cancer (EC), most surgeons rely on intraoperative frozen section (IFS) to determine the risk of nodal metastasis and necessity of lymphadenectomy. IFS remains a weak link in this practice due to its susceptibility to diagnostic errors. As a less invasive alternative, sentinel lymph node (SLN) mapping and ultra-staging have gradually gained acceptance for EC. We aimed to establish the SLN success rate, negative predictive value, and whether SLNs provide useful information for cases misdiagnosed on IFS. From 2013 to 2017, 100 patients (63 low-risk and 37 high-risk EC) underwent hysterectomy, bilateral salpingo-oophorectomy, and SLN. Among them, 56 had additional pelvic lymphadenectomy. A total of 337 SLNs were obtained in 86 cases: 55 bilaterally and 31 unilaterally. The remaining 14 cases failed because of patient obesity or leiomyoma. Pathology ultra-staging detected 2 positive SLNs from 2 patients (1 with isolated tumor cells, 1 with micrometastases). One of 773 nonsentinel pelvic nodes was positive on the contralateral hemi-pelvis in a patient who was mapped unilaterally, resulting in negative predictive value of 100%. During IFS, tumor grade and/or depth of myometrial invasion was misdiagnosed in 22 cases (22%). These errors would have resulted in under-staging in 10 high-risk patients or over-staging in 4 low-risk patients. SLNs were mapped in these misestimated patients, with one revealing metastases. SLN provides invaluable information on nodal status while detecting occult metastases in cases misdiagnosed on IFS. Our findings justify the incorporation of SLN in initial surgery for EC as an offset to IFS diagnostic errors, minimizing their negative impact on patient care.

Sentinel Lymph Node Biopsies in Endometrial Cancer: Practice Patterns among Gynecologic Oncologists in the United States

STUDY OBJECTIVE

To evaluate practice patterns among gynecologic oncologists with regard to sentinel lymph node injection and biopsy in endometrial cancer.

DESIGN

An observational study with no control group.

SETTING AND PATIENTS

Active members of the Society of Gynecologic Oncology.

INTERVENTIONS

After institutional review board approval, we performed an online survey among active members of the Society of Gynecologic Oncology. Members were contacted via e-mail and their answers anonymously captured. Study data were collected using REDCap (REDCap developed by Vanderbilt University, Nashville TN).

MEASUREMENTS AND MAIN RESULTS

Three hundred eighteen of 1216 listed members completed the online survey. The majority of respondents (82.7%) perform sentinel lymph node sampling for endometrial cancer staging. Most technical aspects of sentinel lymph node sampling were consistently applied by the vast majority of respondents, including the choice of indocyanine green as a lymphatic tracer (97.3%) and its injection into the cervix (100%). Other technical aspects of sentinel lymph node sampling, such as the depth of injection, varied among respondents. Although 50.9% of the respondents perform an intraoperative assessment of the uterus by frozen section, only 17.9% assess sentinel lymph nodes by frozen section and/or touch prep. Some of the respondents' approaches are based on limited data, including (1) the use of sentinel lymph node injection and biopsy for high-risk histologies (performed by 69%-75% of the respondents dependent on the histology), (2) omitting side-specific completion lymphadenectomy in the absence of sentinel node mapping (in up to 57.8%), or (3) when lymph node metastases are present (in 39.9%).

CONCLUSION

In summary, despite the growing use of sentinel lymph node injection and biopsy in endometrial cancer, practice patterns vary considerably among providers sampled by this survey. Some of the decisions are based on limited evidence and, in some instances, deviate from current published guidelines.

Current state of sentinel lymph nodes for women with endometrial cancer

Sentinel lymph node (SLN) biopsy has been investigated as an alternative to conventional pelvic and para-aorticlymphadenectomy for the surgical staging of endometrial cancer. Clinical trials have established the accuracy of sentinel nodes in the detecting metastatic disease. Novel advancements in tracers from the historically favored blue dyes and radio labeled colloids to near infrared imaging of fluorescent dyes has improved the ability to detect sentinel nodes and increased options for surgeons. The uterine cervix has been shown to be a feasible and accurate injection site for tracer, though the potential for under-evaluation of the para-aortic nodes remains a controversy, particularly for high-risk cancers. Additionally, sentinel node evaluation provides qualitatively different information than traditional staging techniques by identifying lymph nodes outside of traditional sampling locations and through the identification of very low volume meta static disease implants, such as isolated tumor cells. It is unclear how this altered staging information should be interpreted, guide the prescription of adjuvant therapy and its impact on long term clinical outcomes such as recurrence and survival. In this review we will discuss the evidence that has supported the use of the SLN technique in the staging of endometrial cancer, the options for surgical technique and the implications of managing the results of staging pathology.

Sentinel lymph node mapping using indocyanine green in patients with uterine and cervical neoplasms: restrictions of the method

Purpose

To establish the surgical, demographic and histopathological factors associated with inaccurate sentinel lymph nodes (SLNs) identification using indocyanine green (ICG) and near-infrared (NIR) fluorescence imaging in uterine and cervical neoplasms during both open and laparoscopic surgery.

Methods

We reviewed patients with atypical endometrial hyperplasia (AEH), clinical stage I and II cervical cancer or uterine malignancies who underwent primary surgery with SLN mapping between September 2015 and January 2018. An analysis of patients’ demographics, tumor factors and surgical approach was conducted. Bilateral and overall detection rates were calculated and univariate analysis was performed to estimate factors associated with failed SLN mapping.

Results

A total of 32 patients with uterine and cervical neoplasms were included in the study. The overall detection rate of the SLN was 84% and bilateral detection rate was 75%. There were no statistically relevant differences in overall and bilateral SLN detection rates by BMI, surgical approach or age. Regarding endometrial cancer, there were no differences in SLN detection rates when comparing tumor grade, histology nor myometrial invasion. For SLN detection failure, only the presence of metastatic lymph nodes and lack of surgical experience significantly increased the disability to detect SLNs (p = 0.03, p = 0.04, respectively).

Conclusions

SLN mapping technique using NIR fluorescence imaging with ICG appears to be accurate method in most of the patients with cervical or endometrial carcinoma, regardless of demographic characteristics, tumor-related features and surgical approach. Surgeons’ expertise in that field allows obtaining excellent detection rates.

A feasibility study of sentinel lymph node mapping by cervical injection of a tracer in Japanese women with early stage endometrial cancer

OBJECTIVE

The aim of this study was to investigate the feasibility of sentinel lymph node mapping characterized by a cervical tracer injection in endometrial cancer.

MATERIALS AND METHODS

This retrospective study was carried out using data for 57 patients with endometrial carcinoma who had undergone intraoperative sentinel lymph node mapping and subsequent surgical staging. Technetium colloid and/or indocyanine green was injected into the uterine cervix and a gamma-detecting probe and/or photodynamic eye camera system was used intraoperatively to locate hot spots.

RESULTS

Of the 57 patients, 52 (91.2%) had FIGO Stage I disease. Successful unilateral or bilateral mapping occurred in 54 patients (94.7%) and 46 (80.7%), respectively. The median number of sentinel lymph nodes detected was two (range, 0-5). Following sentinel lymph node mapping, 41 patients (71.9%) underwent pelvic lymphadenectomy alone and 16 (28.1%) full lymphadenectomy. The median number of lymph nodes resected was 17 (range, 8-110). Sentinel lymph nodes were involved in four patients (7.0%), two with macrometastases and two with low-volume metastases. The sensitivity and negative predictive value for detecting lymph node metastasis were both 100%.

CONCLUSION

Sentinel lymph node mapping with the use of cervical tracer injection is highly feasible in Japanese women with early stage endometrial cancer.