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

Abstract

Purpose

To characterize treatment patterns and oncologic outcomes in patients with low-volume lymph node metastasis (isolated tumor cells [ITCs] and micrometastasis [MM]) discovered during sentinel node (SLN) mapping for endometrial carcinoma.

Methods

We identified endometrial cancer cases treated surgically from 9/2005-4/2013 in which SLN mapping was performed. MM was defined as tumor within a lymph node measuring >0.2mm but <2.0mm. ITCs were those measuring ≤0.2mm.

Results

Eight hundred forty-four patients met inclusion criteria. Median age was 61 (range, 30-90). Histology was as follows: endometrioid, 724 (85.8%); serous, 104 (12.3%); and clear cell, 16 (1.9%). Median number of lymph nodes resected was 6 (range, 0-60); median number of SLNs was 2 (range, 0-15). Seven hundred fifty-three patients (89.2%) were node negative, 23 (2.7%) had ITCs only, 21 (2.5%) had MM only, and 47 (5.6%) had macrometastasis. Adjuvant chemotherapy was given to 106 (14%) of 753 node-negative patients, 19 (83%) of 23 patients with ITCs, 17 (81%) of 21 patients with MM, and 42 (89%) of 47 with macrometastasis. Median follow-up was 26 months (range, 0-108). Three-year recurrence-free survival was as follows: node-negative patients, 90% (± 1.5); ITCs only, 86% (± 9.4); MM only, 86% (± 9.7); and macrometastasis, 71% (± 7.2), ( p<0.001).

Conclusion

Patients with ITCs and MM frequently received adjuvant chemotherapy, and had improved oncologic outcomes in comparison to those with macrometastasis to the lymph nodes. Further prospective study is needed to determine optimal post-resection management in patients with ITCs or MM alone.