A prospective investigation of fluorescence imaging to detect sentinel lymph nodes at robotic-assisted endometrial cancer staging

Indocyanine green in gynecologic surgery: Where do we stand? A literature review and meta-analysis

The main objective of this study was to review and perform a meta-analysis of current literature on the use of indocyanine green for sentinel lymph node detection in pelvic gynecologic cancer. We included all studies focusing on indications and procedures associated with the use of ICG in gynecologic surgery and available on the Medline and Pubmed database. For the meta-analysis, random effect models were used for estimation of the 95 % detection rate and 95 % confidence interval, and stratified analyses by cancer type, concentration and localization of injection were performed. A total of 147 articles were included, of which 91 were studied in a meta-analysis. Results concerning detection rate by indocyanine green injection site were found to be 95.1 % and 97.3 % respectively for intracervical injection in 2 or 4 quadrants, and 77.0 % and 94.8 % for hysteroscopic and intradermal injection respectively. Results concerning detection rate by cancer type were 95.8 %, 95.2 %, 94.7 % and 95.7 % respectively for cervical, endometrial, vulvar and endometrial/cervical cancers. Finally, the results concerning detection rate by indocyanine green concentration were 91.2 %, 95.7 %, 96.7 % and 97.7 % for concentrations of <1.25 mg/ml, 1.25 mg/ml, 2.5 mg/ml and 5 mg/ml respectively. In conclusion, indocyanine green is shown to allow highlighting of sentinel lymph nodes with good reliability with an overall indocyanine green detection rate of 95.5 %. Our literature review revealed that indocyanine green feasibility has also been demonstrated in several surgical contexts, notably for reconstructive surgery and detection of endometriosis.

Use of indocyanine green dye for sentinel lymph node mapping in patients with endometrial cancer and a history of iodinated contrast allergy

Objectives

Sentinel lymph node (SLN) mapping is a surgical technique with high accuracy in detecting metastases while limiting morbidity associated with full lymphadenectomy in endometrial cancer. Cervical injection of indocyanine green (ICG) dye is associated with very high SLN detection rates; however, iodinated contrast allergy has traditionally been viewed as a contraindication to ICG use. The objective of this study was to describe the use of ICG in a population of patients with iodinated contrast allergies undergoing surgical staging for endometrial cancer.

Methods

IRB approval was obtained. All patients with clinically early-stage endometrial cancer who underwent minimally invasive surgical staging with SLN mapping with ICG at a single academic institution from 1/1/2017 to 12/31/2020 were identified retrospectively. Patients with reported iodinated contrast allergies prior to surgery were identified. Data were collected through electronic medical record review and compared using descriptive statistics.

Results

820 patients who underwent minimally invasive surgical staging with SLN mapping with ICG were identified, and 25 had documented iodinated contrast allergies. Documented reactions included rash/hives (n = 10, 40 %), anaphylaxis (n = 6, 24 %), shortness of breath (n = 5, 20 %), diarrhea (n = 1, 4 %), and not specified (n = 3, 12 %). A majority (24/25, 96 %) received 4 mg intravenous dexamethasone during induction of general anesthesia as per the institutional enhanced recovery after surgery (ERAS) protocol. No patients experienced allergic reactions or other adverse events after ICG injection.

Conclusions

No patients in this cohort demonstrated an adverse reaction after ICG injection for SLN mapping. This study supports the reasonable safety of ICG in patients with contrast allergies, particularly when routine ERAS protocols containing dexamethasone are utilized.

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.

Let go of the myth: safety of indocyanine green for sentinel lymph node mapping in endometrial cancer

OBJECTIVE

Sentinel lymph node mapping by intracervical indocyanine green injection is the preferred method for surgical staging in endometrial cancer. Adverse reactions to indocyanine green are extremely rare, and information about the safety of this tracer in patients with a history of other allergies, asthma, or comorbidities is limited. We aim to evaluate the rate of adverse reactions to indocyanine green injected during sentinel lymph node mapping in patients with endometrial cancer and review the etiology of such reactions.

METHODS

All patients with endometrial cancer undergoing sentinel lymph node mapping with indocyanine green cervical stroma injection at the Mayo Clinic in Rochester, Minnesota between June 2014 and December 2018 were retrospectively evaluated. Any adverse reaction occurring intra-operatively or within 7 days after surgery was identified. A thorough chart review was performed by an allergy specialist physician for any patient with an allergic-type reaction.

RESULTS

We included 923 patients of which 565 (61.2%) had a history of allergy to antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), other medications, and/or environmental exposures. Of 490 patients who had previously received contrast media, 25 (5.1%) had a history of an adverse reaction. No immediate anaphylaxis or other allergic reactions were observed after indocyanine green injection. 10 (1.1%) patients developed a transient skin reaction within 7 days after surgery. None of these patients had a history of contrast media reaction. Based on timing and clinical/peri-operative history of affected patients, it was determined that skin reactions were likely induced by other newly prescribed medications or contact sensitivity, not administration of indocyanine green.

CONCLUSION

Indocyanine green injection for sentinel lymph node mapping in patients with endometrial cancer caused no immediate/delayed anaphylactic or other severe allergic reactions. This included patients with a history of other allergies, asthma, and comorbidities. The myth of iodine's relationship to allergic reactions must be refuted to allow indocyanine green use in patients with a history of contrast media or shellfish allergy.

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.

Current Approaches to the Management of Patients with Endometrial Cancer

The incidence of endometrial cancer (EC) is rising and healthcare professionals need to be informed about the latest data on the constant developments in the field of its management. With particular interest in the classification and management of EC, we surveyed current literature, national and international data, and guidelines, as well as the latest studies to present the most recent data regarding the management of EC. It became evident that despite the consensus on low-risk EC, there are still controversies surrounding the management of high-risk EC, especially regarding the role of sentinel lymph node biopsy (SLNB). Our aim is to present the old and new perspectives in the management of EC, the different available surgical routes, the possible desire for fertility preservation, the role of adjuvant therapies and the focus on the advantages and the limitations of the implementation of SLNB in therapeutic strategies. It became evident throughout our search and based on literature data that minimally invasive surgery (MIS) leads to satisfying outcomes, thus becoming gradually the preferred route of surgery, while SLNB could provide essential information and guidance about the overall management needed in cases of both low-risk and high-risk EC.

The Feasibility of Sentinel Lymph-Node, Mapped with Indocyanine Green, Biopsy in Endometrial Cancer Patients: A Prospective Study

Background and objectives. Systematic pelvic lymphadenectomy (LND) is an essential part of lymph-node status evaluation in endometrial cancer (EC) patients to tailor the adjuvant treatment. However, it is associated with the post-operative lymphatic complications and does not improve the outcomes of the disease. Indocyanine green (ICG) mapped sentinel lymph-node biopsy (SLB) has recently been introduced into the clinical practice as an alternative for the surgical lymph-node evaluation in EC patients with the potential to decrease LND related complications. The aim of our study was to evaluate the feasibility of ICG mapped SLB in low, intermediate, and high-risk EC patients in a center with no previous experience on endoscopic SLB procedure. Materials and Methods: The prospective study was performed. 170 patients with histologically confirmed EC were included. Sentinel lymph-nodes (SLs) were mapped with ICG dye and removed ahead of the total laparoscopic hysterectomy. Low-risk patients received only SLB, while SLB and LND were performed for intermediate and high-risk patients. Results: The overall detection rate of SLs was 88.8%. Bilateral mapping was achieved in 68.2% of the patients. The overall detection rate for low-risk patients was 93.7%, 85.0% for the intermediate-risk group, and 100% for high-risk patients (p = 0.232). The most common anatomical sites of SLs were the external iliac (45.8% on the right and 46.6% on the left) and obturator regions (20.9% and 25.6%, respectively). Positive lymph-nodes were found in 8 (4.7%) patients. The sensitivity of SLB was 75.0% and negative predictive value (NPV)—97.2%. Conclusions: Even in the center with no previous experience, sentinel lymph-node biopsy using ICG mapping is feasible. However, the favorable outcomes might be associated with the learning process of newly established method.

Anatomical distribution of sentinel lymph nodes in patients with endometrial cancer: a multicenter study

OBJECTIVE

Sentinel lymph node (SLN) mapping represents the standard approach in uterine confined endometrial cancer patients. The aim of this study was to evaluate the anatomical distribution of SLNs and the most frequent locations of nodal metastasis.

METHODS

This was an observational retrospective multicenter study involving eight high volume gynecologic cancer centers in Italy. We reviewed 1576 patients with a histologically confirmed diagnosis of endometrial cancer from September 2015 to June 2020. All patients underwent total hysterectomy with salpingo-ophorectomy and SLN mapping.

RESULTS

A total of 3105 SLNs were mapped and removed, 2809 (90.5%) of these were bilateral and 296 (9.5%) unilateral. The overall detection rate was 93.4% (77.9% bilateral and 15.5% unilateral). The majority of SLNs (80%) and positive SLNs (77.8%) were found at the external iliac and obturator level in both endometrioid and non-endometrioid endometrial cancer. Negative SLNs were more frequent in patients with endometrioid compared with non-endometrioid cancer (91.9% vs 86.1%, p<0.0001). Older patients, a higher body mass index, and non-endometrioid histology were more likely to have 'no mapping' (p<0.0001). Univariate and multivariate analysis showed that higher body mass index and age at surgery were independent predictive factors of empty node packet and fat tissue (p=0.029 and p<0.01, respectively).

CONCLUSION

The most frequent sites of SLNs and metastases were located in the pelvic area below the iliac vessel bifurcation. Our findings showed that older age, a higher body mass index, and non-endometrioid histology had a negative impact on 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.

Comparison of radio-isotope method with 99m technetium and near-infrared fluorescent imaging with indocyanine green for sentinel lymph node detection in endometrial cancer

BACKGROUND

We aimed to compare the detection rate of pelvic sentinel lymph node between the radio-isotope with 99m technetium (99mTc)-labeled phytate and near-infrared fluorescent imaging with indocyanine green in patients with endometrial cancer.

METHODS

This study included 122 patients who had undergone sentinel lymph node mapping using 99mTc and indocyanine green. In the radio-isotope method, sentinel lymph nodes were detected using uterine cervix 99mTc injections the day before surgery. Following injection, the number and locations of the sentinel lymph nodes were evaluated by lymphoscintigraphy. In addition, indocyanine green was injected into the cervix immediately before surgery.

RESULTS

The overall pelvic sentinel lymph node detection rate (at least one pelvic sentinel lymph node detected) was not significantly different between 99mTc (95.9% [117/122]) and indocyanine green (94.3% [115/122]). Similarly, the bilateral sentinel lymph node detection rate was not significantly different between 99mTc (87.7% [107/122]) and indocyanine green (79.5% [97/122]). More than two sentinel lymph nodes per unilateral pelvic lymph node were found in 12.3% (15/122) and 27% (33/122) of cases with 99mTc and indocyanine green, respectively, in the right pelvic side, and 11.5% (14/122) and 32.8% (40/122) of cases with 99mTc and indocyanine green, respectively, in the left pelvic side. indocyanine green showed that there were significantly more than two sentinel lymph nodes in either the left or right pelvic sentinel lymph nodes (P < 0.0001). There was a significant difference in the mean number of total pelvic sentinel lymph nodes between 99mTc (2.2) and indocyanine green (2.5) (P = 0.028) methods.

CONCLUSION

Although indocyanine green is useful for sentinel lymph node identification, we believe it is better to use it in combination with 99mTc until the surgeon is accustomed to it.

Sentinel lymph node biopsy in high-grade endometrial cancer: a systematic review and meta-analysis of performance characteristics

OBJECTIVE

A sentinel lymph node biopsy is widely accepted as the standard of care for surgical staging in low-grade endometrial cancer, but its value in high-grade endometrial cancer remains controversial. The aim of this systematic review and meta-analysis was to evaluate the performance characteristics of sentinel lymph node biopsy in patients with endometrial cancer with high-grade histology (registered in the International Prospective Register of Systematic Reviews with identifying number CRD42020160280).

DATA SOURCES

We systematically searched the MEDLINE, Epub Ahead of Print, MEDLINE In-Process & Other Non-Indexed Citations, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Embase databases all through the OvidSP platform. The search was performed between January 1, 2000, and January 26, 2021. ClinicalTrials.gov was searched to identify ongoing registered clinical trials.

STUDY ELIGIBILITY CRITERIA

We included prospective cohort studies in which sentinel lymph node biopsy were evaluated in clinical stage I patients with high-grade endometrial cancer (grade 3 endometrioid, serous, clear cell, carcinosarcoma, mixed, undifferentiated or dedifferentiated, and high-grade not otherwise specified) with a cervical injection of indocyanine green for sentinel lymph node detection and at least a bilateral pelvic lymphadenectomy as a reference standard. If the data were not reported specifically for patients with high-grade histology, the authors were contacted for aggregate data.

METHODS

We pooled the detection rates and measures of diagnostic accuracy using a generalized linear mixed-effects model with a logit and assessed the risk of bias using the Quality Assessment of Diagnostic Accuracy Studies 2 tool.

RESULTS

We identified 16 eligible studies of which the authors for 9 of the studies provided data on 429 patients with high-grade endometrial cancer specifically. The study-level median age was 66 years (range, 44-82.5 years) and the study-level median body mass index was 28.6 kg/m² (range, 19.4-43.7 kg/m²). The pooled detection rates were 91% per patient (95% confidence interval, 85%-95%; I²=59%) and 64% bilaterally (95% confidence interval, 53%-73%; I²=69%). The overall node positivity rate was 26% (95% confidence interval, 19%-34%; I²=44%). Of the 87 patients with positive node results, a sentinel lymph node biopsy correctly identified 80, yielding a pooled sensitivity of 92% per patient (95% confidence interval, 84%-96%; I²=0%), a false negative rate of 8% (95% confidence interval, 4%-16%; I²=0%), and a negative predictive value of 97% (95% confidence interval, 95%-99%; I²=0%).

CONCLUSION

Sentinel lymph node biopsy accurately detect lymph node metastases in patients with high-grade endometrial cancer with a false negative rate comparable with that observed in low-grade endometrial cancer, melanoma, vulvar cancer, and breast cancer. These findings suggest that sentinel lymph node biopsy can replace complete lymphadenectomies as the standard of care for surgical staging in patients with high-grade endometrial cancer.

The efficiency of a combined injection technique for sentinel lymph node mapping in intermediate-high-risk endometrial cancer

BACKGROUND AND OBJECTIVES

Sentinel lymph node (SLN) mapping was considered for treating endometrial cancer (EC) which was apparent confined to the uterus. Nevertheless, intermediate-high-risk EC patients have super high risk to undergo isolated para-aortic lymph node metastases comparing with low-risk patients. Therefore, this investigation aimed to compare the efficacy of two SLN methods in detecting para-aortic lymph node metastases.

METHODS

According to SLN mapping injection methods, intermediate-high-risk EC patients who received both SLN mapping and systematic lymphadenectomy were divided into the combined group (fundal and cervical injections) and the cervical group (cervical injection only).

RESULTS

The para-aortic SLN detection rate in the combined group (40.4%) was higher than that in the cervical group (4.4%) with p < 0.001. While the differences concerning the sensitivity, false-negative rate, and negative predictive value between the two groups were not significant. The survival outcomes of patients were comparable between the two groups.

CONCLUSION

Our data showcased that the combined (fundal and cervical) injection had a higher detection rate of para-aortic SLNs than cervical injection only. The efficiency of SLN mapping and the survival outcomes were not significantly different between the two groups. Further investigations are warranted to assess the value of combined injection regarding SLN technique.

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.

Sentinel lymph node biopsy in patients with endometrial cancer and an indocyanine green or iodinated contrast reaction - A proposed management algorithm

OBJECTIVE

To describe the incidence of adverse reactions to indocyanine green (ICG) administered during sentinel lymph node (SLN) biopsy for endometrial cancer, and to propose an ICG management algorithm for these patients.

METHODS

All patients who underwent surgery for endometrial cancer with SLN biopsy using ICG from 1/2017 to 8/2020 were identified using a single-institution prospective database. Surgical adverse events (SAEs) related to the procedure were identified. A review of the literature was performed.

RESULTS

In all, 1414 patients met inclusion criteria and were evaluated. Sixty-seven (4.7%) patients had a history of either an iodine or contrast allergy. No patients had a history of documented ICG allergy. Among patients with an iodine or contrast allergy, 65 (97%) received a corticosteroid with or without diphenhydramine prior to ICG administration. One hundred five patients (7.4%) experienced 116 SAEs. Among these patients, 3 experienced potentially allergic SAEs possibly related to ICG administration. After thorough chart review, however, the likelihood these SAEs were due to ICG appeared low. No patients experienced an anaphylactic response after ICG admission.

CONCLUSION

There were no anaphylactic reactions to ICG intracervical administration during 1414 consecutive SLN biopsies, including in patients with a documented iodine or contrast allergy. Intracervical injection of ICG is safe, and premedication using corticosteroids with or without diphenhydramine prior to SLN biopsy is a reasonable strategy in patients with iodinated contrast allergy.

Endometrial cancer: A society of gynecologic oncology evidence-based review and recommendations

INTRODUCTION

In 2014, the Society of Gynecologic Oncology's Clinical Practice Committee published a clinical update reviewing the treatment of women with endometrial cancer. At that time, there had been significant advances in the diagnosis, work-up, surgical management, and available treatment options allowing for more optimal care of affected women. Despite these advances, the incidence of endometrial cancer as well as the deaths attributable to the disease have continued to rise; from 1987 to 2014 there has been a 75% increase in cases and almost 300% increase in endometrial cancer deaths. Fortunately, since then, there has been progress in the treatment of patients with endometrial cancer with increased utilization of molecular pathology, greater understanding of genetic predisposition, enhanced methods for lymph node assessment, a broader understanding of the efficacy of radiation and chemotherapy, and a more efficient approach to survivorship and surveillance. The purpose of this document is to present a comprehensive review of this progress.

MANUSCRIPT DEVELOPMENT PROCESS

The authors reviewed the available evidence, contributed to the development of this manuscript, provided critical review of the guidelines, and finalized the manuscript recommendations. The review was also presented to and approved by the Society of Gynecologic Oncology (SGO) Clinical Practice Committee, SGO Publications Committee, and the SGO board members prior to submission for publication. The recommendations for this manuscript were developed by a panel of gynecologic oncologists who were members of the SGO Clinical Practice and Education Committees. Panelists reviewed and considered evidence from current uterine cancer literature. The terminology used in these guidelines was adopted from the ASCCP management guidelines [1] using a two-part rating system to grade the strength of recommendation and quality of evidence (Table 1). The rating for each recommendation is given in parentheses.

Update on new imaging technologies in sentinel node detection

In most cancers, lymph node status is the most critical factor impacting the evolution of the disease and the overall survival. Identifying potential nodal metastasis allows the oncologist to adjust the stage and, consequently, the patient's treatment. For this reason, a precise evaluation of the regional nodes is mandatory. In gynecological cancers, pelvic, paraaortic, and inguinal nodes are the region most frequently interested by metastasis. In the past years, comprehensive lymphadenectomy was the standard of care for endometrial, cervical, ovarian, and vulvar cancers. However, after introducing the sentinel lymph node (SNL) biopsy in breast cancers, this technique has gained much more interest in gynecology oncology. Several studies have shown that SLN allows an evaluation of the node status without the complications related to the lymphadenectomy that impacts the patient's quality of life. In this review, we discuss the role of SNL biopsy in gynecological cancers and the technique's evolution over the years. Moreover, we debate the OSNA method for SLN analysis that is recently introduced for uterine cancer.

Design, synthesis and characterization of a fluorescently labeled functional analog of full-length human ghrelin

Human ghrelin receptor (GHSR) is a recognized prospective target in the diagnosis and therapy of multiple cancer types. To gain a better understanding of this receptor signaling system, we have synthesized a novel full-length ghrelin analog that is fluorescently labeled at the side-chain of a C-terminal cysteine extension. This analog exhibited nanomolar affinity and potency for the ghrelin receptor. It shows comparable efficacy with that of endogenous ghrelin. The fluorescently-labeled ghrelin analog is a valuable tool for in vitro imaging of cell lines that express ghrelin receptor.

Sentinel lymph node biopsy in endometrial cancer: state of the art

Endometrial cancer (EC) is the most common gynecological neoplasm in developed countries. In literature, there are discordant data regarding the therapeutic value of systematic lymphadenectomy whereas the importance of lymph node status for determining prognosis and the need for adjuvant treatment is undoubted. Given the low risk of lymph-node metastases in the apparent early-stage disease and the significant surgical and postoperative risks when performing a complete pelvic lymphadenectomy, the surgical approach in these patients is controversial, ranging from no nodal evaluation to comprehensive pelvic and aortic lymphadenectomy. The recent introduction of sentinel node mapping represents the mid-way between the execution and omission of node dissection in EC patients. Indeed, the sentinel node mapping has rapidly emerged as an alternative to complete lymphadenectomy to reduce morbidity. In the present review, we discuss the role of sentinel node mapping in the surgical management of EC evaluating all aspects of this procedure.

Sentinel lymph node mapping in high-risk endometrial cancer: a systematic review and meta-analysis

BACKGROUND

In the staging of endometrial cancer (EC), the role of sentinel lymph node (SLN) mapping for high-risk EC is still unclear.

METHODS

Two authors independently reviewed abstracts and full-text articles for inclusion and assessed study quality. English studies published in PubMed, Embase, and Cochrane Library before 20th SEP, 2019 were retrieved to perform a systematic evaluation and meta-analysis which evaluate the detection rate and diagnostic accuracy of SLN mapping in high-risk EC. Statistical analysis was conducted using stata14.0 software.

RESULTS

A total of 12 studies were included, including 758 high-risk EC patients. The detection rate of SLN mapping was 84.8% (95% CI, 79.9-89.6%). The pooled bilateral detection rate was 67.0% (95% CI, 56.8-77.3%). The pooled para-aortic detection rate was 8.4% (95% CI, 1.8-14.9%). The pooled sensitivity was 87% (95% CI, 79-92%), and the pooled specificity was 98% (95% CI, 96-99%). Pooled negative predictive value (NPV) was 97.7% (95% CI, 96.4-99.1%), AUC =0.99 (95% CI, 0.97-0.099).

CONCLUSIONS

SLN mapping still has a high detection rate and diagnostic accuracy in high-risk EC. SLN mapping is a reliable alternative to systematic lymph node dissection, but its prognostic effect on high-risk EC is yet to be further studied and verified by large sample studies.

Learning curve for sentinel lymph node mapping in gynecologic malignancies

BACKGROUND AND OBJECTIVES

Only a few studies have reported the learning curve for sentinel lymph node (SLN) detection in gynecologic malignancies. We investigated the learning curve for SLN detection during robot-assisted laparoscopic surgery for endometrial and cervical carcinomas.

METHODS

This retrospective analysis included patients with stage IA to IIA1 cervical cancer or stage I to III endometrial cancer who underwent SLN mapping using indocyanine green during robot-assisted laparoscopic surgery performed by a single surgeon. Learning curves were analyzed in consecutive cases using SLN detection rates and the cumulative sum (CUSUM) method.

RESULTS

SLN mapping was achieved in 81.25% (65/80), 77.50% (62/80), and 66.25% (53/80) of the cases involving the right, left, and simultaneous bilateral pelvic areas, respectively. Learning curve analysis based on the cumulative detection rate showed initial fluctuations followed by stabilization; the time required for proficiency was discordant among the LN regions. However, the CUSUM method showed proficient mapping of the right, left, and bilateral SLNs after 27 to 28 cases.

CONCLUSION

At least 27 cases were required for SLN mapping proficiency in gynecologic cancer; the learning period could influence the surgical quality. Further studies are warranted to confirm the impact of this learning curve on disease outcomes.

Sentinel lymph node mapping in endometrial and cervical cancer: a survey of practices and attitudes in gynecologic oncologists

Objective

To determine patterns among gynecologic oncologists in sentinel lymph node mapping (SLNM) for endometrial cancer (EC) and cervical cancer (CC).

Methods

A online survey assessing the practice of SLNM, including incidence, patterns of usage, and reasons for non-use was distributed to Society of Gynecologic Oncology candidate and full members in August 2017. Descriptive statistics and univariate analysis was performed.

Results

The 1,117 members were surveyed and 198 responses (17.7%) were received. Of the 70% (n=139) performing SLNM, the majority reported use for both CC and EC (64.0%) or EC alone (33.1%). In those using SLNM in EC, the majority (86.6%) performed SLNM in >50% of cases for all patients (56.3%), International Federation of Gynecology and Obstetrics grade 1 (43.0%) and 2 (42.2%). Reported benefits of SLNM in EC were reduced surgical morbidity (89.6%), lymphedema (85.2%), and operative time (63.7%). Among those using SLNM for CC, the majority (73.1%) did so in >50% of cases. In EC, 77.2% and 21.3% reported that micro-metastatic disease (0.2–2.0 cm) and isolated tumor cells (ITCs) should be treated as node positive, respectively. In those not using SLNM for EC (n=64) and CC (n=105), concerns were regarding efficacy of SLNM and lack of training. When queried regarding training, 73.7% felt that SLNM would impact skill in full lymphadenectomy (LND).

Conclusion

The SLNM is utilized frequently among gynecologic oncologists for EC and CC staging. Common reasons for non-uptake include uncertainty of current data, lack of training and technology. Concerns exist regarding impact of SLNM in fellowship training of LND.

Reproductive surgery: decreasing skills and advancing technology-an existential conundrum

Our article endeavors to be both a review of the recent past and a preview of the future of reproductive surgery. By reflecting on the rate of technological advancement over the past decade, we attempt to predict the trajectory of the next. We also delve into the changing nature and practical challenges of the practice of gynecologic surgery for the reproductive endocrinology and infertility subspecialist. We will explain how technological advances may alter our perception and expectations regarding the indications, timing and extent of surgical intervention in the infertile patient and in the patient seeking preservation of fertility. This review does not aim to be comprehensive, choosing instead to focus on those innovations that hold, in our view, true potential to shape the future of surgical practice. Ours is primarily a technology review. As such, it does not focus on novel surgical techniques, including uterine transplantation and ovarian tissue transplantation.

Triple tracer (blue dye, indocyanine green, and Tc99) compared to double tracer (indocyanine green and Tc99) for sentinel lymph node detection in endometrial cancer: a prospective study with random assignment

OBJECTIVE

Sentinel lymph node (SLN) mapping is increasingly being used in the treatment of apparent early-stage endometrial cancer. The aim of this study was to evaluate whether three tracers (blue dye, indocyanine green (ICG), and technetium-99 (Tc99)) performed better than two (ICG and Tc99).

STUDY DESIGN

Prospective study of all consecutive patients (n=163) diagnosed with clinical early-stage endometrial cancer from 2015 to 2017. All patients were randomly assigned to receive a mixture of ICG and Tc99 with or without blue dye. Subgroup analysis for detection rates was performed for each group (double versus triple tracer).

RESULTS

One hundred and fifty-seven patients met the inclusion criteria. Eighty patients received ICG and Tc99 with unilateral and bilateral SLN detection rates of 97.5% and 81.3%, respectively. Seventy-seven patients received all three tracers with unilateral and bilateral detection rates of 93.5% and 80.5%, respectively. Only one patient in the triple tracer group was detected by blue dye alone. No significant differences were noticed in unilateral or bilateral detection rates between the two groups, nor in the detection of lymph node metastasis.

CONCLUSION

The addition of blue dye to ICG and Tc99 did not demonstrate any improvement in SLN detection.

Robotic-Assisted Sentinel Lymph Node Mapping With Indocyanine Green in Pelvic Malignancies: A Systematic Review and Meta-Analysis

Objective: Newer technologies such as near-infrared (NIR) imaging of the fluorescent dye indocyanine green (ICG) and daVinci Xi Surgical System have become promising tools for sentinel lymph node (SLN) mapping. This meta-analysis was conducted to comprehensively evaluate the diagnostic value of SLN in assessing lymph nodal metastasis in pelvic malignancies, using ICG with NIR imaging in robotic-assisted surgery. Materials and Methods: A literature search was conducted using PubMed for studies in English before April 2019. The detection rate, sensitivity of SLN detection of metastatic disease, and factors associated with successful mapping (sample size, study design, mean age, mean body mass index, type of cancer) were synthesized for meta-analysis. Results: A total of 17 articles including 1,059 patients were finally included. The reported detection rates of SLN ranged from 76 to 100%, with a pooled average rate of 95% (95% CI: 93-97; 17 studies). The sensitivity of SLN detection of metastatic disease ranged from 50 to 100% and the pooled sensitivity was 86% (95% CI: 75-94; 8 studies). There were no complications related to ICG administration reported. Conclusions: NIR imaging system using ICG in robotic-assisted surgery is a feasible and safe method for SLN mapping. Due to its promising performance, it is considered to be an alternative to a complete pelvic lymph node dissection.

Green versus blue: Randomized controlled trial comparing indocyanine green with methylene blue for sentinel lymph node detection in endometrial cancer

OBJECTIVE

To ascertain the increase in detection rate of sentinel lymph node (SLN) associated with the use of indocyanine green (ICG) in comparison with methylene blue dye in women with endometrial cancer.

METHODS

For this randomized controlled trial, all patients underwent SLN mapping after injection of blue dye on one side of the cervix and ICG on the other side. Randomization was for the side (right vs. left) on which ICG was used so that each patient's contralateral hemipelvis (HP) served as a control to her ipsilateral HP. We performed a two-tailed, normal-approximate McNemar test for paired-matched data. The primary endpoint was the difference in SLN detection rate for each HP according to the dye used.

RESULTS

This trial included 132 patients, and 46 patients underwent robotic-assisted surgery while 86 had standard laparoscopic surgery. Successful detection of SLN was 90.9% using ICG and 64.4% using blue dye (p < 0.0001). There were no differences in the duration of the SLN procedure (median 10 min per HP) and number of SLN per HP (mean 1.2) according to the dye used. The SLN detection rates for either dye were very similar whether the surgical approach was robotic (mean BMI 45) or laparoscopic (mean BMI 29). Crossover of dye to the contralateral HP was present in 3% of cases.

CONCLUSION

The use of ICG instead of blue dye results in a 26.5% (95% CI 17.4%-35.6%) increase of SLN detection rates per HP in women with endometrial cancer.

Preoperative Prediction of Lymph Nodal Metastases in Endometrial Carcinoma: Is it Possible?: A Literature Review

BACKGROUND

Lymph node status is one of the most important prognostic factors in endometrial cancer and crucial for deciding adjuvant therapy.

OBJECTIVE

The aim of the study was to assess the different models used to predict lymphatic nodal disease.

SEARCH STRATEGY

A literature search was conducted to detect the relevant studies.

INCLUSION CRITERIA

Relevant papers comparing the preoperative modality with the final histopathological results including randomized clinical trials, case-control studies, and any publications with a minimum of 50 patients in the report.

RESULTS

Molecular-based predictors are still far from a practical application. Preoperative radiological scans (positron emission tomography, computed tomography, magnetic resonance imaging, and ultrasound) have shown the best predictor of lymphatic dissemination. However, there is currently no ideal model available, which can be used within standard clinical care.

CONCLUSIONS

Surgical staging still remains the criterion standard in the determination of lymph node status in endometrial cancer.

Two-step sentinel lymph node mapping strategy in endometrial cancer staging using fluorescent imaging: A novel sentinel lymph node tracer injection procedure

OBJECTIVE

The current sentinel lymph node (SLN) tracer injection procedure for endometrial cancer commonly uses cervical injection, which can detect SLNs of the uterine cervix but not the uterine body. This study describes an SLN tracer injection procedure, titled two-step SLN mapping, which can identify SLNs of the uterine body and cervix using fluorescent imaging with indocyanine green (ICG) and results of SLN biopsy.

METHODS

In 50 consecutive patients with endometrial cancer, two-step SLN mapping was performed during laparoscopic surgical staging with the PINPOINT® real-time fluorescence imaging system. The first step was to identify SLNs of the uterine body. In total, 4-6 mL of ICG was injected into the bilateral uterine cornual areas, and lymphatic channels were traced, followed by identification and removal of paraaortic SLNs. The second step was to identify SLNs of the uterine cervix by injecting 4 mL of ICG into the cervix. After harvesting the mapped pelvic SLNs, complete pelvic and paraaortic lymphadenectomy was performed to validate the two-step SLN mapping strategy.

RESULTS

Our two-step SLN mapping strategy produced excellent SLN detection rates: 100% (50/50) overall for SLNs; 98.0% (49/50) for pelvic SLNs; 94.0% (47/50) for bilateral SLNs; and 86.0% (43/50) for paraaortic SLNs. We detected microscopic metastasis in harvested SLNs of 4 patients (8.0%). The sensitivity, specificity, and negative predictive value of SLN detection were all 100%. There was no false negative case.

CONCLUSION

The two-step SLN mapping strategy to identify lymph nodes from the uterine fundus and cervix was feasible. This strategy could be more accurate in identifying paraaortic lymph node metastasis than the cervical injection method.

A practical guide for the use of indocyanine green and methylene blue in fluorescence-guided abdominal surgery

Near-infrared (NIR) fluorescence imaging is gaining clinical acceptance over the last years and has been used for detection of lymph nodes, several tumor types, vital structures and tissue perfusion. This review focuses on NIR fluorescence imaging with indocyanine green and methylene blue for different clinical applications in abdominal surgery with an emphasis on oncology, based on a systematic literature search. Furthermore, practical information on doses, injection times, and intraoperative use are provided.

The Utility of Sentinel Lymph Node Mapping in High-Grade Endometrial Cancer

OBJECTIVE

The aim of this study was to report the utility and false-negative rates of sentinel lymph node (SLN) mapping during surgical staging of women with high-grade, apparent uterine-confined endometrial cancer.

METHODS

This was a single-institution study performed at a high-volume academic center. From December 2012 to December 2015, women with high-grade endometrial cancer (grade 3 endometrioid, serous, clear cell, and carcinosarcoma) underwent SLN mapping via cervical injection followed by robot-assisted total laparoscopic hysterectomy and completion lymphadenectomy. Ultrastaging of SLNs was performed in patients with tumors with any degree of myoinvasion. Patient demographics, SLN test characteristics, treatment, and recurrence outcomes were prospectively evaluated for analysis.

RESULTS

Fifty-two patients with high-grade histologic findings underwent SLN mapping followed by completion lymphadenectomy. The median patient age was 64 years, and median body mass index was 31.8 kg/m2. Most patients had either serous (46%) or grade 3 endometrioid histology (27%) on preoperative biopsy. Nine patients had nodal metastases, 7 of whom had metastases identified in SLNs. No low-volume nodal metastases were identified on ultrastaging. Two patients had false-negative SLN mapping (22%). After a median follow-up of 15.6 months, 14 recurrences (27%) were diagnosed; all were distant or multisite relapses. Sentinel lymph node mapping did not impact the choice of adjuvant therapy or recurrence risk in node-positive patients.

CONCLUSIONS

Sentinel lymph node detection of metastases in patients with high-grade endometrial cancer is high, but false-negative results were encountered. More research is needed to determine whether SLN mapping can safely replace systemic lymphadenectomy in women with high-risk histologic findings.

Evidence for the use of robotically assisted surgery in gynecologic cancers

PURPOSE OF REVIEW

Robotically assisted laparoscopy has been introduced in the armamentarium of gynaecologic oncology surgeons. A lot of studies compared robotic surgery and laparotomy when the real issue is to demonstrate the interest and added value of robotically assisted laparoscopy versus standard laparoscopy. In this review, we will describe the most meaningful indications and advantages of robotically assisted laparoscopy in gynaecologic oncology.

RECENT FINDINGS

The learning curve for advanced procedures in robot-assisted laparoscopy is shorter and easier than with the standard laparoscopy, especially for beginners. In most of the series, operating time is longer with robot, but complication rates are often decreased, especially in obese patients with a conversion rate to laparotomy that is decreased compared with standard laparoscopy. Robot-assisted laparoscopy can be used for surgery of high-risk endometrial cancer, staging of early-ovarian cancer, and pelvic exenteration in case of recurrent malignancies. Furthermore, more recent robots allow performing sentinel node biopsy in endometrial or cervical cancer using fluorescence detection with indocyanine green.

SUMMARY

The spreading of robotic surgery led to an enhancement of minimal invasive surgical approach in general, and to the development of new indications in gynaecologic oncology. The superiority of robot-assisted laparoscopy still has to be demonstrated with properly designed trials.

Sentinel lymph node mapping in endometrial cancer: a systematic review and meta-analysis

Endometrial cancer is the most frequent tumor in the female reproductive system, while the sentinel lymph node (SLN) mapping for diagnostic efficacy of endometrial cancer is still controversial. This meta-analysis was conducted to evaluate the diagnostic value of SLN in the assessment of lymph nodal involvement in endometrial cancer. Forty-four studies including 2,236 cases were identified. The pooled overall detection rate was 83% (95% CI: 80-86%). The pooled sensitivity was 91% (95% CI: 87-95%). The bilateral pelvic node detection rate was 56% (95% CI: 48-64%). Use of indocyanine green (ICG) increased the overall detection rate to 93% (95% CI: 89-96%) and robotic-assisted surgery also increased the overall detection rate to 86% (95% CI: 79-93%). In summary, our meta-analysis provides strong evidence that sentinel node mapping is an accurate and feasible method that performs well diagnostically for the assessment of lymph nodal involvement in endometrial cancer. Cervical injection, robot-assisted surgery, as well as using ICG, optimized the sensitivity and detection rate of the technique. Sentinel lymph mapping may potentially leading to a greater utilization by gynecologic surgeons in the future.

A prospective validation study of sentinel lymph node mapping for high-risk endometrial cancer

OBJECTIVE

Sentinel lymph node (SLN) mapping continues to evolve in the surgical staging of endometrial cancer (EC). The purpose of this trial was to identify the sensitivity, false negative rate (FNR) and FN predictive value (FNPV) of SLN compared to complete pelvic and para-aortic lymphadenectomy (LAD) in women with high-risk EC.

METHODS

Women with high-risk EC (grade 3, serous, clear cell, carcinosarcoma) were enrolled in this prospective surgical trial. All patients underwent preoperative PET/CT and intraoperative SLN biopsy followed by LAD. Patients with peritoneal disease on imaging or at the time of surgery were excluded. Patients were evaluable if SLN was attempted and complete LAD was performed.

RESULTS

123 patients were enrolled between 4/13 and 5/16; 101 were evaluable. At least 1 SLN was identified in 89% (90); bilateral detection 58%, unilateral pelvic 40%, para-aortic only 2%. Indocyanine green was used in 61%, blue dye in 28%, and blue dye and technetium in 11%. Twenty-three pts. (23%) had ≥1 positive node. In 20/23, ≥1 SLN was identified and in 19/20 the SLN was positive. Only 1 patient had bilateral negative SLN and positive non-SLNs on final pathology. Overall, sensitivity of SLN was 95% (19/20), FNR was 5% (1/20) and FNPV was 1.4% (1/71). If side-specific LAD was performed when a SLN was not detected, the FNR decreased to 4.3% (1/23).

CONCLUSION

This prospective trial demonstrated that SLN biopsy plus side-specific LAD, when SLN is not detected, is a reasonable alternative to a complete LAD in high-risk endometrial cancer.

Sentinel lymph node assessment in endometrial cancer: a systematic review and meta-analysis

BACKGROUND

In the staging of endometrial cancer, controversy remains regarding the role of sentinel lymph node mapping compared with other nodal assessment strategies.

OBJECTIVE

We conducted a systematic review to evaluate the diagnostic accuracy and clinical impact of sentinel lymph node mapping in the management of endometrial cancer.

DATA SOURCES

We searched Medline, Embase, and the Cochrane Central Registry of Controlled trials for studies published in English before March 25, 2016 (PROSPERO CRD42016036503).

STUDY ELIGIBILITY CRITERIA

Studies were included if they contained 10 or more women with endometrial cancer and reported on the detection rate, sensitivity, and/or impact on treatment or survival of sentinel lymph node mapping.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two authors independently reviewed abstracts and full-text articles for inclusion and assessed study quality. The detection rate, sensitivity, and factors associated with successful mapping (study size, body mass index, tumor histology and grade, injection site, dye type) were synthesized through random-effects meta-analyses and meta-regression.

RESULTS

We identified 55 eligible studies, which included 4915 women. The overall detection rate of sentinel lymph node mapping was 81% (95% confidence interval, 77-84) with a 50% (95% confidence interval, 44-56) bilateral pelvic node detection rate and 17% (95% confidence interval, 11-23) paraaortic detection rate. There was no difference in detection rates by patient body mass index or tumor histology and grade. Use of indocyanine green increased the bilateral detection rate compared with blue dye. Additionally, cervical injection increased the bilateral sentinel lymph node detection rate but decreased the paraaortic detection rate compared with alternative injection techniques. Intraoperative sentinel lymph node frozen section increased the overall and bilateral detection rates. The sensitivity of sentinel node mapping to detect metastases was 96% (95% confidence interval, 91-98); ultrastaging did not improve sensitivity. Compared with women staged with complete lymphadenectomy, women staged with sentinel lymph node mapping were more likely to receive adjuvant treatment.

CONCLUSION

Sentinel lymph node mapping is feasible and accurately predicts nodal status in women with endometrial cancer. The current data favors the use of cervical injection techniques with indocyanine green. Sentinel lymph mapping may be considered an alternative standard of care in the staging of women with endometrial cancer.

Indocyanine green fluorescence imaging of lymph nodes during robotic-assisted laparoscopic operation for endometrial cancer. A prospective validation study using a sentinel lymph node surgical algorithm

OBJECTIVE

A sentinel lymph node (SLN) strategy may have particular value in endometrial cancer (EC) because a therapeutic effect of lymphadenectomy per se is unproven. The aim was to evaluate indocyanine green (ICG) and near-infrared (NIR) fluorescence mapping using a surgical algorithm.

METHODS

From November 2012 through December 2015, women with apparently early stage EC underwent robot-assisted laparoscopic hysterectomy including ICG fluorescence SLN mapping following the Memorial Sloane Kettering Cancer Center (MSKCC) surgical algorithm.

RESULTS

Among 108 patients included, ≥1 SLNs was identified in 104 (96%), bilaterally in 84 (78%) and unilaterally in 20 patients (18%). Four patients failed SLN mapping. All SLN-positive patients had pelvic SLNs. Median number of nodes were 4.0 and 6.0 (p<0.001), when SLNs only and SLNs plus non-SLNs were removed, respectively. Lymph node metastases were detected in 17 patients (16%). One patient who failed SLN mapping had a non-SLN metastasis. The remaining 16 patients had metastases in SLNs, 12 in SLNs only and four in both SLNs and non-SLNs. Routine pathology detected 75% of patients with cancer positive SLNs while 25% were based on extended pathology. Lymph node metastases were found among 9% with low-, 11% with intermediate- and 32% with high-risk profiles, respectively.

CONCLUSIONS

We have reproduced the high total and bilateral SLN mapping using cervical ICG injection and NIR fluorescence. Practical application of the MSKCC algorithm allowed high lymph node metastasis detection in combination with a low extent of lymph node removal.

Laparoscopic Sentinel Node Mapping in Endometrial Cancer After Hysteroscopic Injection of Indocyanine Green

STUDY OBJECTIVE

To report the detection rate (DR) of sentinel lymph nodes (SLNs) in endometrial cancer (EC) patients after hysteroscopic injection of indocyanine green (ICG) and laparoscopic near-infrared (L-NIR) fluorescence mapping.

DESIGN

Prospectively collected data (Canadian Task Force classification II-2).

SETTING

Gynecologic oncology referral center.

PATIENTS

Consecutive patients with apparent early-stage endometrioid EC scheduled for surgical treatment: total laparoscopic hysterectomy, bilateral salpingo-oophorectomy, SLN mapping.

INTERVENTIONS

The mapping technique consisted in an intraoperative hysteroscopic peritumoral injection of 5 mg ICG followed by L-NIR fluorescence mapping. Evaluations of the SLN DR and sites of mapping were performed.

MEASUREMENTS AND MAIN RESULTS

A total of 57 procedures was performed. Patient mean age was 60 years (range, 28-80) and mean body mass index was 28.2 kg/m² (range, 19-43). At least 1 SLN was detected in 89.5% of the whole population (51/57). After the first 16 cases, L-NIR camera technical improvement led to a 95% DR (39/41). The mean number of harvested SLNs was 4.1 (range. 1-8), and in 47% of cases SLNs mapped to aortic nodes (24/51). Bilateral pelvic mapping was found in 74.5% of cases (38/51). Three patients had SLN metastases: 1 in the pelvic area only, 1 both in the pelvic and aortic area, and 1 presented with 2 metastatic aortic SLNs with negative pelvic SLNs. Overall, 2 of 3 node-positive patients (67%) had aortic SLN involvement. No adverse events were reported.

CONCLUSIONS

Laparoscopic SLN mapping after the hysteroscopic injection of ICG has comparable DRs with both radioactive tracer series and ICG series with cervical injection, overcoming the need for radioactive substances. Hysteroscopic injection leads to a higher mapping in the aortic area compared with cervical injection. Further investigation is warranted on this topic.

Advances in fluorescent-image guided surgery

Fluorescence imaging is increasingly gaining intraoperative applications. Here, we highlight a few recent advances in the surgical use of fluorescent probes.