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

Area of Science:

• Gynecologic Oncology
• Surgical Pathology
• Nuclear Medicine Imaging

Background:

• Nodal status is a critical prognostic factor in endometrial cancer (EC).
• Systematic lymphadenectomy carries significant morbidity.
• Sentinel lymph node (SLN) mapping is a less invasive alternative, 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 if this method is reliable in settings where advanced imaging agents are unavailable.

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% with a side-specific completion algorithm.
• Side-specific sensitivity and NPV reached 100%; no mapping-related complications occurred.

Conclusions:

• SLN mapping with methylene blue and optional technetium-99m is a reliable method for nodal staging in EC.
• The addition of a side-specific completion algorithm significantly enhances diagnostic accuracy.
• This technique offers a viable, less invasive staging option, particularly when fluorescence imaging is not available.