Uptake and outcomes of sentinel lymph node mapping in women undergoing minimally invasive surgery for endometrial cancer

Comparison of tracer application methods for sentinel lymph node detection in open surgery patients with endometrial cancer: a retrospective cohort study

BACKGROUND

This study aimed to evaluate the effectiveness of different tracers´ application techniques for sentinel lymph node (SLN) detection in women with endometrial cancer undergoing laparotomy. Additionally, potential risk factors for SLN detection failure were assessed.

METHODS

We retrospectively analyzed data from 248 endometrial cancer patients who underwent abdominal surgery with SLN mapping between January 2020 and March 2024. Statistical analyses were conducted using the Wilcoxon rank sum test for continuous variables and either Pearson's chi-square test or Fisher's exact test for categorical variables, with a significance level set at p < 0.05.

RESULTS

Group I + S consisted of 147 women with intracervical and subserosal tracers´application and group I + I included 101 women with intracervical and intrafundal application. Successful detection of SLN on both sides was achieved in 39.9% (99/248) of all patients, in 38.1% (56/147) in the I + S group and in 42.6% (43/101) in the I + I group, respectively. SLNs were identified in 32.7% (81/248) of all patients on only one side of the pelvis, in 31.3% (46/147) in the I + S and in 34.7% (35/101) in the I + I group, respectively. No SLNs were detected in 27.4% (68/248) of all subjects, comprising 30.6% (45/147) from the I + S and 22.8% (23/101) from the I + I group. Although the success rate of SLN detection was higher in the I + I group and on the right side of the pelvis regardless of the detection method, these differences were not statistically significant. An age exceeding 66.3 years was recognized as a critical risk factor for successful detection, other followed factors did not demonstrate a statistically significant impact on overall detection success. Additional significant risk factors were identified: depth of tumor myometrial invasion on the right side, history of pelvic surgery, and total tumor volume on the left side.

CONCLUSIONS

The study did not reveal significant differences in SLN mapping success between the groups receiving intracervical + intrafundal and intracervical + subserosal tracers´applications among endometrial cancer patients treated via open surgery. Overall, older age emerged as the most critical risk factor for SLN detection failure, while other assessed factors did not show a statistically significant impact on overall detection success.

TRIAL REGISTRATION

Institution University Hospital Královské Vinohrady, Prague, Czech Republic.

REGISTRATION NUMBER

EK-VP-21-0-2023. Date of registration 7-JUN-2023. This study was retrospectively registered in compliance with the Declaration of Helsinki.

Sentinel node mapping decreases the risk of failed detection of isolated positive para-aortic lymph node in endometrial cancer

BACKGROUND

Isolated positive para-aortic lymph node metastasis in endometrial cancer is an uncommon event, ranging from 1% to 3%.

OBJECTIVE

Our aim was to evaluate the impact of sentinel lymph node (SLN) mapping on the risk of isolated positive para-aortic lymph node metastasis.

METHODS

We retrospectively evaluated a series of 426 patients who underwent SLN mapping with at least one SLN detected from January 2013 to December 2021 (SLN group) compared with a historical series of 209 cases who underwent a systematic pelvic and para-aortic lymphadenectomy between June 2007 and April 2015 (LND group). Isolated para-aortic lymph node metastasis recurrences were included in the SLN group analysis.

RESULTS

In the SLN group, 168 cases (39.4%) had backup systematic lymphadenectomy, and 56 (13.1%) had positive lymph nodes compared with 34 (16.3%) in LND group (p=0.18). The SLN group had higher rates of minimally invasive surgeries (p<0.001) and presence of lymphovascular space invasion (p<0.001). Moreover, SLN group had fewer other uterine risk factors, such as high-grade tumors (p<0.001), and deep myometrial invasion (p<0.001). We found that SLN mapped outside the pelvis at pre-sacral, common iliac areas, and para-aortic regions in 2.8% (n=12), 11.5% (n=49), and 1.6% (n=7) of cases, respectively. Overall, 52 (12.2%) patients had positive SLNs, and 3 (5.7%) positive SLNs were found outside the pelvis-one in the pre-sacral region, one in the common iliac area, and one in the para-aortic region. An isolated para-aortic lymph node was found in only 2 (0.5%) cases in the SLN group compared with 7 (3.3%) cases in the LND group (p=0.004).

CONCLUSIONS

SLN protocol accurately predicts lymph node status and may decrease the risk of failed identification of isolated para-aortic lymph node metastasis compared with systematic lymphadenectomy.

Utilization and Surgical Outcomes of Sentinel Lymph Node Biopsy for Endometrial Intraepithelial Neoplasia

OBJECTIVE

To describe the rate and surgical outcomes of sentinel lymph node (SLN) biopsy in patients with endometrial intraepithelial neoplasia (EIN).

METHODS

We conducted a cohort study that used the prospective American College of Surgeons National Surgical Quality Improvement Program database. Women with EIN on postoperative pathology who underwent minimally invasive hysterectomy from 2012 to 2020 were included. The cohort was dichotomized based on the performance of SLN biopsy. Patients' characteristics, perioperative morbidity, and mortality were compared between patients who underwent SLN biopsy and those who did not. Postoperative complications were defined using the Clavien-Dindo classification system.

RESULTS

Overall, 4,447 patients were included; of those, 586 (13.2%) underwent SLN biopsy. The proportion of SLN biopsy has increased steadily from 0.6% in 2012 to 26.1% in 2020 ( P <.001), with a rate of 16% increase per year. In a multivariable regression that included age, body mass index (BMI), and year of surgery, a more recent year of surgery was independently associated with an increased adjusted odds ratio of undergoing SLN biopsy (1.51, 95% CI, 1.43-1.59). The mean total operative time was longer in the SLN biopsy group (139.50±50.34 minutes vs 131.64±55.95 minutes, P =.001). The rate of any complication was 5.9% compared with 6.7%, the rate of major complications was 2.3% compared with 2.4%, and the rate of minor complications was 4.1% compared with 4.9% for no SLN biopsy and SLN biopsy, respectively. In a single complications analysis, the rate of venous thromboembolism was higher in the SLN biopsy group (four [0.7%] vs four [0.1%], P =.013). In a multivariable regression analysis adjusted for age, BMI, American Society of Anesthesiologists classification, uterus weight, and preoperative hematocrit, the performance of SLN biopsy was not associated with any complications, major complications, or minor complications.

CONCLUSION

The performance of SLN biopsy in EIN is increasing. Sentinel lymph node biopsy for EIN is associated with an increased risk of venous thromboembolism and a negligible increased surgical time.

Is it safe to operate selected low-risk endometrial cancer patients in secondary hospitals?

INTRODUCTION

The aim of this study was to assess the accuracy of a preoperative screening algorithm in identifying low-risk endometrial cancer (EC) patients to ensure optimal care.

METHODS

A total of 277 patients with primary EC confirmed through biopsy underwent magnetic resonance imaging (MRI). Patients with risk factors for advanced high-risk EC, such as non-endometrioid histology, high-grade differentiation status, deep myometrial invasion, or spread beyond the uterine corpus, were systematically excluded. The remaining preoperatively screened patients with stage IA low-grade endometrioid EC (EEC) (n = 93) underwent surgery in a tertiary hospital. The accuracy of the preoperative diagnosis was evaluated by comparing the findings with the postoperative histopathological results. Disease-free survival (DFS) and overall survival (OS) were analyzed using 8-year follow-up data.

RESULTS

Postoperative histopathological analysis revealed that all patients had grade 1-2 EEC localized to the corpus uteri. Only three patients had deep myometrial invasion (stage IB), but they remained disease-free after 6-9 years of follow-up. The median follow-up time for all patients was 8.7 years. The DFS was 7.6 years, and the OS was 8.6 years. Two patients with stage IA grade 1 EEC experienced relapse and, despite treatment, died of EC. No other EC-related deaths occurred.

CONCLUSIONS

The screening algorithm accurately identified low-risk EC patients without compromising survival. Therefore, the algorithm appears to be feasible for selecting patients for surgery in secondary hospitals.

Does sentinel node mapping impact morbidity and quality of life in endometrial cancer?

OBJECTIVES

To evaluate the prevalence of post-operative complications and quality of life (QoL) related to sentinel lymph node (SLN) biopsy vs systematic lymphadenectomy in endometrial cancer.

METHODS

A prospective cohort included women with early-stage endometrial carcinoma who underwent lymph node staging, grouped as follows: SLN group (sentinel lymph node only) and SLN+LND group (sentinel lymph node biopsy with addition of systematic lymphadenectomy). The patients had at least 12 months of follow-up, and QoL was assessed by European Organization for Research and Treatment of Cervical Cancer Quality of Life Questionnaire 30 (EORTC-QLQ-C30) and EORTC-QLQ-Cx24. Lymphedema was also assessed by clinical evaluation and perimetry.

RESULTS

152 patients were included: 113 (74.3%) in the SLN group and 39 (25.7%) in the SLN+LND group. Intra-operative surgical complications occurred in 2 (1.3%) cases, and all belonged to SLN+LND group. Patients undergoing SLN+LND had higher overall complication rates than those undergoing SLN alone (33.3% vs 14.2%; p=0.011), even after adjusting for confound factors (OR=3.45, 95% CI 1.40 to 8.47; p=0.007). The SLN+LND group had longer surgical time (p=0.001) and need for admission to the intensive care unit (p=0.001). Moreover, the incidence of lymphocele was found in eight cases in the SLN+LND group (0 vs 20.5%; p<0.001). There were no differences in lymphedema rate after clinical evaluation and perimetry. However, the lymphedema score was highest when lymphedema was reported by clinical examination at 6 months (30.1 vs 7.8; p<0.001) and at 12 months (36.3 vs 6.0; p<0.001). Regarding the overall assessment of QoL, there was no difference between groups at 12 months of follow-up.

CONCLUSIONS

There was a higher overall rate of complications for the group undergoing systematic lymphadenectomy, as well as higher rates of lymphocele and lymphedema according to the symptom score. No difference was found in overall QoL between SLN and SLN+LND groups.

Therapeutic Benefit of Systematic Lymphadenectomy in Node-Negative Uterine-Confined Endometrioid Endometrial Carcinoma: Omission of Adjuvant Therapy

Simple Summary

Endometrial cancer is the most common gynecological tract malignancy in developed countries. Extrauterine disease, in particular lymph node metastasis, is an important prognostic factor. Nevertheless, pelvic lymphadenectomy is not considered to have a therapeutic benefit, as it did not improve survival in randomized studies. However, lymphadenectomy may have a therapeutic benefit if adjuvant therapy can be omitted without decreasing oncological outcomes, as the long-term quality of life is maintained by avoiding morbidities associated with adjuvant therapy. In intermediate- and high-risk endometrioid endometrial carcinomas, adjuvant therapy may be safely omitted without decreasing long-term survival by open surgery including systematic pelvic and para-aortic lymphadenectomy when patients are node-negative. Systematic lymphadenectomy may remove undetectable low-volume lymph node metastasis in both pelvic and para-aortic regions, and open surgery may reduce vaginal recurrence even without vaginal brachytherapy. However, lymphadenectomy may not improve survival in elderly patients and patients with p53-mutant tumors.

Abstract

Endometrial cancer is the most common gynecological tract malignancy in developed countries, and its incidence has been increasing globally with rising obesity rates and longer life expectancy. In endometrial cancer, extrauterine disease, in particular lymph node metastasis, is an important prognostic factor. Nevertheless, pelvic lymphadenectomy is not considered to have a therapeutic benefit, as it did not improve survival in randomized studies. However, lymphadenectomy may have a therapeutic benefit if adjuvant therapy can be omitted without decreasing oncological outcomes, as the long-term quality of life is maintained by avoiding morbidities associated with adjuvant therapy. In intermediate- and high-risk endometrioid endometrial carcinomas, adjuvant therapy may be safely omitted without decreasing long-term survival by open surgery including systematic pelvic and para-aortic lymphadenectomy when patients are node-negative. Systematic lymphadenectomy may remove undetectable low-volume lymph node metastasis in both pelvic and para-aortic regions, and open surgery may reduce vaginal recurrence even without vaginal brachytherapy. However, lymphadenectomy may not improve survival in elderly patients and patients with p53-mutant tumors. In this review, I discuss the characteristics of lymph node metastasis, the methods of lymph node assessment, and the therapeutic benefits of systematic lymphadenectomy in patients with intermediate- and high-risk endometrioid endometrial carcinoma.

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.