Sentinel Lymph Node Mapping in Endometrial Cancer: Our Initial Experience in a Resource Limited Setting

Area of Science:

• Gynecology
• Surgical Oncology
• Pathology

Background:

• Nodal status is a critical prognostic factor in endometrial cancer (EC).
• Systematic lymphadenectomy carries significant morbidity.
• Sentinel lymph node (SLN) mapping presents a less invasive approach, but data are limited without indocyanine green.

Purpose of the Study:

• To evaluate the efficacy of SLN mapping using methylene blue, with or without technetium-99m, for nodal staging in endometrial cancer.
• To assess detection rates, sensitivity, and negative predictive value (NPV) of the SLN mapping technique.
• To determine the reliability of SLN mapping as an alternative to systematic lymphadenectomy.

Main Methods:

• Prospective study of 29 women with FIGO stage I-III EC.
• Cervical injection of methylene blue, with or without technetium-99m, for SLN mapping.
• Routine ultrastaging and performance of full lymphadenectomy in high-risk cases.

Main Results:

• Overall and bilateral SLN detection rates were 75% and 48%, respectively.
• Patient-level sensitivity was 71% with an NPV of 88%, increasing to 86% sensitivity and 100% side-specific sensitivity/NPV with a completion algorithm.
• Nodal metastases were found in 31% of patients; lymphovascular space invasion and 50% myometrial invasion were associated with metastasis.

Conclusions:

• SLN mapping with methylene blue (± technetium) and a side-specific algorithm offers reliable nodal staging for EC.
• This technique is effective even without fluorescence imaging, providing a valuable alternative to extensive lymphadenectomy.
• No mapping-related complications were observed, highlighting the safety of the procedure.