Diagnostic accuracy of frozen section and patterns of nodal spread in high grade endometrial cancer: A secondary outcome of the SENTOR prospective cohort study

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

AIM

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Treatment of node-positive endometrial cancer: chemotherapy, radiation, immunotherapy, and targeted therapy

OPINION STATEMENT

The standard of treatment for node-positive endometrial cancer (FIGO Stage IIIC) in North America has been systemic therapy with or without additional external beam radiation therapy (RT) given as pelvic or extended field RT. However, this treatment paradigm is rapidly evolving with improvements in systemic chemotherapy, the emergence of targeted therapies, and improved molecular characterization of these tumors. The biggest question facing providers regarding management of stage IIIC endometrial cancer at this time is: what is the best management strategy to use with regard to combinations of cytotoxic chemotherapy, immunotherapy, other targeted therapeutics, and radiation that will maximize clinical benefit and minimize toxicities for the best patient outcomes? While clinicians await the results of ongoing clinical trials regarding combined immunotherapy/RT as well as management based on molecular classification, we must make decisions regarding the best treatment combinations for our patients. Based on the available literature, we are offering stage IIIC patients without measurable disease postoperatively both adjuvant chemotherapy and IMRT with carboplatin, paclitaxel, and with or without pembrolizumab/dostarlimab as primary adjuvant therapy. Patients with measurable disease post operatively, high risk histologies, or stage IV disease receive chemoimmunotherapy, and vaginal brachytherapy is added for those with uterine risk factors for vaginal recurrence. In the setting of endometrioid EC recurrence more than 6 months after treatment, patients with pelvic nodal and vaginal recurrence are offered IMRT and brachytherapy without chemotherapy. For measurable recurrence not suitable for pelvic radiation alone, chemoimmunotherapy is preferred as standard of care.

Sentinel lymph node mapping in endometrial cancer: Current evidence and practice

Surgical staging with total hysterectomy, bilateral salpingo-oophorectomy, and lymph node assessment is the standard of care for patients with clinical early-stage endometrial cancer. Traditionally, complete pelvic and para-aortic lymphadenectomy (LND) was performed to assess for nodal metastases; however, numerous prospective studies have demonstrated that sentinel lymph node biopsy has similar diagnostic accuracy, and is an acceptable alternative to complete LND. This has led to a paradigm shift in endometrial cancer staging.