Low-Volume Lymph Node Metastasis Discovered During Sentinel Lymph Node Mapping for Endometrial Carcinoma

Area of Science:

• Gynecologic Oncology
• Surgical Pathology
• Cancer Research

Background:

• Sentinel lymph node (SLN) mapping is crucial for staging endometrial carcinoma.
• Accurate characterization of low-volume lymph node metastasis, including isolated tumor cells (ITCs) and micrometastasis (MM), is essential for treatment decisions.

Purpose of the Study:

• To characterize treatment patterns and oncologic outcomes in endometrial cancer patients with low-volume lymph node metastasis (ITCs and MM) detected via SLN mapping.
• To compare outcomes between patients with ITCs, MM, and macrometastasis.

Main Methods:

• Retrospective analysis of 844 endometrial cancer patients undergoing SLN mapping (September 2005 - April 2013).
• Definition of ITCs (≤0.2 mm) and MM (>0.2 mm and <2.0 mm) within lymph nodes.
• Evaluation of adjuvant chemotherapy use and 3-year recurrence-free survival rates based on metastasis volume.

Main Results:

• Of 844 patients, 2.7% had ITCs only, 2.5% had MM only, and 5.6% had macrometastasis.
• Adjuvant chemotherapy was administered to 83% of ITC and 81% of MM patients.
• Three-year recurrence-free survival was 86% for ITCs and MM, significantly better than 71% for macrometastasis (p < 0.001).

Conclusions:

• Patients with ITCs and MM demonstrate improved oncologic outcomes compared to those with lymph node macrometastasis.
• Adjuvant chemotherapy is frequently utilized for patients with ITCs and MM.
• Prospective studies are warranted to establish optimal post-resection management strategies for endometrial cancer patients with ITCs or MM.