Randomized comparison between sentinel lymph node mapping using indocyanine green plus a fluorescent camera versus lymph node dissection in clinical stage I-II endometrial cancer: a Korean Gynecologic Oncology Group trial (KGOG2029/SELYE)

Role of sentinel lymph node biopsy with indocyanine green and site of injection in endometrial cancer

PURPOSE OF REVIEW

The aim of the present narrative review is to summarize the state of art on sentinel lymph node biopsy (SLNB) in endometrial cancer, with a special focus on indocyanine green (ICG) as adopted tracer.

RECENT FINDINGS

Over the years, the surgical nodal staging in patients with endometrial cancer has been intensively investigated. Traditionally, systematic pelvic and para-aortic lymphadenectomy represented the gold standard surgical treatment to assess nodal involvement of the tumor. Through the last two decades, SLNB has gradually replaced lymphadenectomy as a more targeted procedure. A great heterogeneity of tracers and injection techniques have been proposed to perform SLNB. However, no universally accepted recommendations are still available.

SUMMARY

SLNB has nowadays almost replaced pelvic lymphadenectomy in low-risk endometrial cancers, offering a better safety profile while being related to a comparable nodal involvement sensitivity. Currently, ICG is considered to be the most used tracer among others. Different injection sites have been proposed, with different detection features. While ICG cervical injection is nowadays the suggested technique for SLNB, noncervical injection techniques, such as hysteroscopic and combined procedures, seem to have a better accuracy in para-aortic nodal assessment, which have a role in high-risk endometrial cancers.

Implementation of sentinel node biopsy in high-risk endometrial cancer

PURPOSE OF REVIEW

Endometrial cancer is the most common gynecologic malignancy and sentinel lymphnode biopsy is accepted as a valid alternative to lymphadenectomy for staging purposes. Recently, sentinel node biopsy has been also extended to high-risk disease where risk of nodal involvement is higher.

RECENT FINDINGS

Our review focuses on the definition of high-risk disease and how there are different concepts of high-risk in the scientific community. While the sensitivity of sentinel node biopsy has been established and accepted in lower risk endometrial cancers, only in recent years retrospective and prospective evidence has been published. Ultrastaging allows to identify more nodal disease that would normally be overlooked by traditional staging, allowing proper adjuvant therapy to be administered. The longstanding question of whether lymphadenectomy in high-risk settings is a therapeutic or a staging procedure remains open. Retrospective data, however, show that oncologic outcomes are not compromised by sentinel node biopsy.

SUMMARY

Sentinel node biopsy is a valid alternative to traditional, more extensive nodal staging: with the addition of ultrastaging, it has more sensitivity than lymphadenectomy with less surgical morbidity. Ongoing trials will definitively establish if oncological outcomes are affected by sentinel node biopsy, but retrospective data are encouraging.

Nodal staging in high and high-intermediate risk endometrial cancer surgery: Which role in the molecular classification era?

OBJECTIVES

Nodal staging contributes to risk group definition and the indication to adjuvant treatment in endometrial cancer (EC) patients. However, the role of nodal assessment evolved and requires redefinition. Primary outcome of the study was to assess the impact of surgical nodal staging in defining high-risk (HR) EC. Secondary outcome was to evaluate the contribution of nodal assessment to the decision for adjuvant treatment in both high-risk and high-intermediate risk (HIR) patients submitted to surgery.

METHODS

Clinical stage I-II EC patients with postoperative diagnosis of HR and HIR disease were included. The contribution of nodal staging in prognostic groups allocation was assessed by reviewing HR patients to identify those without any other feature of such class (non-endometrioid histology, p53abn immunohistochemistry, post-operative T3-T4 disease) and HIR cases to assess how nodal staging affected adjuvant treatment indication. Descriptive statistics were conducted to describe the two populations.

RESULTS

Fifty-seven patients were included, 46 with HR and 11 with HIR disease. Chemotherapy and external-beam radiotherapy (EBRT) were proposed in 40 HR patients. Considering histology, immunohistochemical profile and FIGO stage, high risk classification was exclusively relied on nodal involvement in 2/46 cases (4.3 %). Omitting retroperitoneal staging, one of them would have been classified in the intermediate risk group and the other as HIR: without nodal staging, chemotherapy and EBRT would have been omitted in 1/40 (2.5 %) case. Among HIR patients, chemotherapy was proposed in 7/11 cases and EBRT in all cases. Adjuvant chemotherapy was indicated in 5/6 (83.3 %) and omitted in 1/6 (16.7 %) pN0 patient (stage Ib G2, substantial LVSI). In HIRpN0 patients, omitting nodal staging could have changed adjuvant treatment indication in 1/6 (16.7 %) case. In HIRpNx patients, adjuvant chemotherapy was omitted in one patient (stage II, grade 2 and LVSI negative): nodal staging unavailability might have changed indication to chemotherapy in 1/5 (20 %) case, without changing indication to EBRT. Unavailable nodal staging could globally be related to omission of chemotherapy in 2/57 (3.5 %) patients and of EBRT in 1/57 (1.8 %) patient.

CONCLUSIONS

In this series, nodal staging had limited impact on definition of HR class and on the choice of adjuvant treatment in HR and HIR EC patients.

Clinical outcomes of sentinel node navigation surgery in patients with preoperatively estimated stage IA endometrial cancer and evaluation of validity for continuing sentinel node navigation surgery based on dispersion of recurrence probability

BACKGROUND

To evaluate the feasibility of the use and continuation of sentinel lymph node navigation surgery (SNNS) as an alternative to pelvic lymph node dissection (PLND) for patients with preoperatively estimated stage IA endometrial cancer.

METHODS

This retrospective study selected the electronic medical records of all patients who had received CT scans and MRI imaging before surgery from April 1, 2009 to March 31, 2021. Sentinel lymph nodes (SLNs) were detected by administrating 99mTc-phytate and/or indocyanine green into the cervix, and the clinical outcomes of the patients who underwent SNNS or PLND were evaluated. Furthermore, in case of nodal recurrence, a new procedure to determine whether the facility should continue with SNNS or not was developed that compares the maximum likelihood hypothesis and an alternative one based on recurrence rates.

RESULTS

Among 137 patients, SLN biopsies with ultrastaging were performed on 91 patients. The SLN detection rate was 95.6%. Over a 59-month median observation period, no statistically significant differences were shown in overall survival, disease-specific survival and disease-free survival between the SNNS and PLND groups when introducing the propensity score method (p-values: 0.06, 0.153, and 0.625, respectively). Our procedure demonstrated that, in our department without recurrence up to the 65th attempt, it was possible to continue SNNS if a recurrence occurs at the 66th attempt.

CONCLUSION

This study suggests the validity of SNNS as an alternative to PLND. Even in the absence of evidence from randomized controlled trials, we can confirm the validity of continuing SNNS using our procedure.

Endometrial cancer intraoperative sentinel lymph node identification can effectively guide treatment

OBJECTIVE

To explore the significance of intraoperative sentinel lymph node (SLN) identification in endometrial cancer.

METHODS

We retrospectively analyzed the clinical data of 56 patients with intraoperative SLN recognition (group A) and 50 patients without intraoperative SLN recognition (group B). SLN and pelvic abdominal lymph node distribution, SLN recognition rate, SLN recognition effect, mortality, the incidence of adverse events, and cumulative survival rate were statistically analyzed.

RESULTS

SLN were identified and removed in 41 of the 56 patients, with a recognition rate of 82.14% (46/56). The sensitivity of SLN was 83.72%, the specificity was 84.62%, and the negative predictive value was 61.11%. There were 15 patients with no SLN metastasis found in the pathological examination during the operation, among which two patients with poorly differentiated adenocarcinoma and clinical stage II patients underwent immunohistochemical staining, and three patients showed SLN micro-metastasis but no cancer tissue metastasis in the lymph node dissection. There was no significant difference in the incidence of total adverse events between group A and group B (P>0.05). The cumulative survival rate of group A was higher than that of group B (P=0.018).

CONCLUSION

Intraoperative SLE identification can avoid false negative results, is safe and feasible, and can prolong the survival time of patients with endometrial cancer.

Comparison of oncological outcomes between sentinel lymph node biopsy and complete lymphadenectomy for endometrial cancer

AIM

Sentinel lymph node (SLN) mapping allows node-negative patients to be spared from the surgical comorbidities associated with total lymphadenectomy. This study aimed to evaluate the oncological outcomes of SLN biopsy versus complete lymph node dissection in patients with early-stage endometrial carcinoma.

METHODS

Retrospective analyses were performed in patients with pathologically confirmed endometrioid endometrial carcinoma, who underwent minimally invasive surgical staging with SLN biopsy or complete lymph node dissection at Yonsei Cancer Center between 2015 and 2019.

RESULTS

A total of 301 patients were included in this study. Eighty-two patients underwent SLN biopsy, while 219 underwent complete lymph node dissection. There were no significant differences in patient characteristics between the two groups. In terms of operative characteristics, the SLN biopsy-only group had a significantly shorter surgical duration (p < 0.001) than the lymphadenectomy group. The mean follow-up period was 41.4 months. There were no differences in progression-free survival (PFS) and overall survival (OS) between the two groups (SLN biopsy vs. complete lymph node dissection; p = 0.798 and 0.301, respectively). Multivariate analysis revealed that SLN biopsy was not an independent prognostic factor for PFS or OS.

CONCLUSION

Our results showed that SLN biopsy provided oncological outcomes similar to those of lymphadenectomy.