Comparing indocyanine green, technetium, and blue dye for sentinel lymph node mapping in endometrial cancer

Endometrial and cervical cancer patients with multiple sentinel lymph nodes at laparoscopic ICG mapping: How many are enough?

PURPOSE

The adoption of a sentinel lymph node (SLN) algorithm and the presence of high bilateral detection rates have been associated with increased accuracy of SLN mapping in cervical and endometrial cancer patients. In this context, the significance of the number of SLNs removed has not yet been investigated. The aim of this study was to evaluate (a) whether or not a higher SLN removal count is associated with a reduced false-negative rate and (b) which clinical factors correlate with the number of SLNs removed.

METHODS

Patients with cervical or endometrial cancer who underwent SLN mapping with bilateral SLN detection followed by lymphadenectomy were evaluated retrospectively. On the basis of the mean number of the SLNs removed, the patients were divided in two groups: Group 1 included patients with up to 3 SLNs removed and Group 2 included patients with more than 3 SLNs removed. Factors predicting a higher SLN count were evaluated using univariate and multivariate analysis.

RESULTS

Eighty-four patients met the inclusion criteria. The two groups consisted of 42 patients each and differed only by the median SLN count. Two endometrial cancer patients in Group 1 had false-negative pelvic SLNs and isolated para-aortic metastases; no false-negative SLNs were recorded in Group 2 (p = n.s.). The results of multivariate analysis indicted that the number of SLNs removed was influenced only in cases where the operating surgeon had performed more than 20 laparoscopic ICG SLN mappings.

CONCLUSIONS

A higher SLN count does not seem to increase the accuracy of SLN mapping in cervical and endometrial cancer patients.

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

BACKGROUND

The accuracy of sentinel lymph node mapping has been shown in endometrial cancer, but studies to date have primarily focused on cohorts at low risk for nodal involvement. In our practice, we acknowledge the lack of benefit of lymphadenectomy in the low-risk subgroup and omit lymph node removal in these patients. Thus, our aim was to evaluate the feasibility and accuracy of sentinel node mapping in women at sufficient risk for nodal metastasis warranting lymphadenectomy and in whom the potential benefit of avoiding nodal procurement could be realized.

OBJECTIVE

To evaluate the detection rate and accuracy of fluorescence-guided sentinel lymph node mapping in endometrial cancer patients undergoing robotic-assisted staging.

STUDY DESIGN

One hundred twenty-three endometrial cancer patients undergoing sentinel lymph node sentinel node mapping using indocyanine green were prospectively evaluated. Two mL (1.0 mg/mL) of dye were injected into the cervical stroma divided between the 2-3 and 9-10 o'clock positions at the time of uterine manipulator placement. Before hysterectomy, the retroperitoneal spaces were developed and fluorescence imaging was used for sentinel node detection. Identified sentinel nodes were removed and submitted for touch prep intraoperatively, followed by permanent assessment with routine hematoxylin and eosin levels. Patients then underwent hysterectomy, bilateral salpingo-oophorectomy, and completion bilateral pelvic and periaortic lymphadenectomy based on intrauterine risk factors determined intraoperatively (tumor size >2 cm, >50% myometrial invasion, and grade 3 histology).

RESULTS

Of 123 patients enrolled, at least 1 sentinel node was detected in 119 (96.7%). Ninety-nine patients (80%) had bilateral pelvic or periaortic sentinel nodes detected. A total of 85 patients met criteria warranting completion lymphadenectomy. In 14 patients (16%) periaortic lymphadenectomy was not feasible, and the mean number of pelvic nodes procured was 13 (6-22). Of the 71 patients undergoing pelvic and periaortic lymphadenectomy, the mean nodal count was 23.2 (8-51). Of patients undergoing lymphadenectomy, 10.6% had lymph node metastasis on final hematoxylin and eosin evaluation. Notably, the sentinel node was the only positive node in 44% of cases. There were no cases in which final pathology of the sentinel node was negative and metastatic disease was detected upon completion lymphadenectomy in the non-sentinel nodes (no false negatives), yielding a sensitivity of 100%. Of the 14 sentinel nodes ultimately found to harbor metastases, 3 were negative on touch prep, yielding a sensitivity of 78.6% for intraoperative detection of sentinel node involvement. In all 3 of the false-negative touch preps, final pathology detected a single micrometastasis (0.24 mm, 1.4 mm, 1.5 mm). As expected, there were no false-positive results, yielding a specificity of 100%. No complications related to sentinel node mapping or allergic reactions to the dye were encountered.

CONCLUSION

Intraoperative sentinel node mapping using fluorescence imaging with indocyanine green in endometrial cancer patients is feasible and yields high detection rates. In our pilot study, sentinel node mapping identified all women with Stage IIIC disease. Low false-negative rates are encouraging, and if confirmed in multi-institutional trials, this approach would be anticipated to reduce the morbidity, operative times, and costs associated with complete pelvic and periaortic lymphadenectomy.

Sentinel Node Mapping in Cervical and Endometrial Cancer: Indocyanine Green Versus Other Conventional Dyes-A Meta-Analysis

BACKGROUND

Historically, blue dyes, (99)Tc or a combination of the two tracers have been used for sentinel lymph node (SLN) mapping in cervical and endometrial cancer patients. Indocyanine green (ICG), as a tracer, has been recently introduced in this setting. Our goal was to assess the differences in overall and bilateral detection rates as well as in false-negative rates among the different tracers.

METHODS

The electronic databases PubMed, MEDLINE, and Scopus were searched in January 2016 by searching the terms "sentinel lymph node" and "dye" and "indocyanine green," and "cervical cancer" or "endometrial cancer." Series comparing different tracers injected intracervically and reporting the detection rate and/or SLN false-negative rate were selected.

RESULTS

Forty-five studies were retrieved. Six studies including 538 patients met selection criteria. Compared with blue dyes, ICG SLN mapping had higher overall (odds ratio [OR] 0.27; 95 % confidence interval [CI] 0.15-0.50; p < 0.0001) and bilateral detection rates (OR 0.27; 95 % CI 0.19-0.40; p < 0.00001). No differences were found between ICG and (99)TC, although these results are based on data of a single series. No differences in overall and bilateral detection rates were found between ICG and the combination of blue dyes and (99)TC. The pooled analysis of false-negative rates data showed no difference in false-negative rates between tracers.

CONCLUSIONS

In cervical and endometrial cancer, ICG SLN mapping seems to be equivalent to the combination of blue dyes and (99)TC in terms of overall and bilateral detection rates. Its safety profile and ease of use may favor its employment respect to conventional tracers.

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

OBJECTIVES

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

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

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

Evaluation of sentinel lymph nodes in vulvar, endometrial and cervical cancers

Sentinel lymph node (SLN) biopsies are a sensitive tool in evaluating lymph nodes for multiple cancers, and in some diseases they decrease morbidity in both the short- and long-term. SLN detection in gynecologic malignancies has been studied extensively over the past decade. We review the current literature on SLN dissection in vulvar, endometrial and cervical cancers. Large, well-designed trials in each of the three types of cancer have demonstrated high sensitivity and low false-negative rates when SLN biopsy is performed in the correct patients and with an appropriate technical approach. In all of these cases the addition of ultra-staging to conventional pathology yields increased detection of micrometastatic disease. Biopsy of the sentinel nodes is feasible and safe in early vulvar malignancies, with multiple studies describing low recurrence rates in those women who have with negative SLNs. There does not appear to be a survival benefit to lymphadenectomy over SLN biopsy and quality of life is improved in women undergoing SLN biopsy. Optimal treatment strategies for women with positive nodal biopsies, particularly in cases with micrometastatic disease, remain unclear. Multiple large studies investigating the utility of SLN biopsy in endometrial malignancy have found that sentinel nodal status is a reliable predictor of metastases in women with low-risk disease. Prospective studies are ongoing and suggest sentinel nodal detection may soon become widely accepted as an alternative standard of care for select cases of endometrial cancer. In cervical cancer, SLN biopsy is accurate for diagnosing metastatic disease in early stage tumors (≤ 2 cm diameter or stage ≤ IB2) where the risk of metastasis is low. It is unknown if women who undergo SLN biopsy alone will have different survival outcomes than women who undergo complete lymphadenectomy in these cases. In a specific population of women with vulvar cancer, SLN dissection is an effective and safe alternative to complete dissection. It can be offered as an alternative management strategy in these women. In women who do undergo SLN biopsy, it is associated with improved quality of life. Promising evidence supporting the utility of SLN dissection in endometrial and cervical cancer continues to emerge, and it may soon become a reasonable option for select patients. However, continued research and refinement of appropriate patient selection and long-term follow-up are necessary.

Laparoscopic Indocyanine Green Sentinel Lymph Node Mapping in Endometrial Cancer

Background

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

Objective

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

Methods

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

Results

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

Conclusions

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

Impact of Indocyanine Green for Sentinel Lymph Node Mapping in Early Stage Endometrial and Cervical Cancer: Comparison with Conventional Radiotracer (99m)Tc and/or Blue Dye

Purpose

To compare the detection rate (DR) and bilateral optimal mapping (OM) of sentinel lymph nodes (SLNs) in women with endometrial and cervical cancer using indocyanine green (ICG) versus the standard technetium-99m radiocolloid (^99mTc) radiotracer plus methylene or isosulfan blue, or blue dye alone.

Methods

From October 2010 to May 2015, 163 women with stage I endometrial or cervical cancer (118 endometrial and 45 cervical cancer) underwent SLN mapping with ^99mTc with blue dye, blue dye alone, or ICG. DR and bilateral OM of ICG were compared respectively with the results obtained using the standard ^99mTc radiotracer with blue dye, or blue dye alone.

Results

SLN mapping with ^99mTc radiotracer with blue dye was performed on 77 of 163 women, 38 with blue dye only and 48 with ICG. The overall DR of SLN mapping was 97, 89, and 100 % for ^99mTc with blue dye, blue dye alone, and ICG, respectively. The bilateral OM rate for ICG was 85 %—significantly higher than the 58 % obtained with ^99mTc with blue dye (p = 0.003) and the 54 % for blue dye (p = 0.001). Thirty-one women (19 %) had positive SLNs. Sensitivity and negative predictive value of SLN were 100 % for all techniques.

Conclusions

SLNs mapping using ICG demonstrated higher DR compared to other modalities. In addition, ICG was significantly superior to ^99mTc with blue dye in terms of bilateral OM in women with early stage endometrial and cervical cancer. The higher number of bilateral OM may consequently reduce the overall number of complete lymphadenectomies, reducing the duration and additional costs of surgical treatment.

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

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

Sentinel node detection in endometrial cancer using indocyanine green and fluorescence imaging-a case report

Sentinel lymph node mapping in endometrial cancer can help to provide the prognostic information needed while avoiding the morbidity associated with a complete lymphadenectomy. Studies with blue dye and technetium colloid have only given about 80% detection rates whereas with indocyanine green injection and fluorescence imaging, it gives about 88–100% detection rates. Herein, we report a case where indocyanine green was injected intracervically and sentinel nodes were detected at the paraaortic nodal area.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Survival of Patients with Uterine Carcinosarcoma Undergoing Sentinel Lymph Node Mapping

PURPOSE

This study was designed to evaluate the outcome of patients with uterine carcinosarcoma undergoing sentinel lymph node (SLN) mapping.

METHODS

A prospectively maintained database was reviewed for all women with uterine cancer treated at our institution from January 1, 1998 to August 31, 2014. Patients were grouped based on whether they had undergone SLN mapping or routine lymphadenectomy at the time of staging. SLN evaluation was performed according to a standard institutional protocol that incorporates a surgical algorithm and pathologic ultrastaging.

RESULTS

We identified 136 patients with uterine carcinosarcoma who had undergone lymph node evaluation; 48 had surgical staging with SLN mapping and 88 had routine lymphadenectomy consisting of pelvic and/or para-aortic lymph node dissection. Stage distribution for the SLN group included: stage I, 31 (65 %); stage II, 1 (2 %); stage III, 11 (23 %); stage IV, 5 (10 %). Stage distribution for the non-SLN group included: stage I, 48 (55 %); stage II, 4 (4 %); stage III, 19 (22 %); stage IV, 17 (19 %) (p = 0.4). Median number of lymph nodes removed was 8 and 20, respectively (p ≤ 0.001). Median number of positive nodes was similar between the groups (p = 0.2). Of the 67 patients who had a documented recurrence, 14 of 20 (70 %) in the SLN and 34 of 47 (74 %) in the non-SLN group demonstrated a distant/multifocal pattern of recurrence. There was no difference in median progression-free survival between the groups (23 vs. 23.2 months, respectively; p = 0.7).

CONCLUSIONS

Progression-free survival in women with uterine carcinosarcoma undergoing SLN mapping with adjuvant therapy appears similar to that of patients treated before the incorporation of the SLN protocol. Additional prospective studies with longer follow-up are necessary to validate these early results.