Extent of lymph node dissection and overall survival in patients with uterine carcinosarcoma, papillary serous and endometrioid adenocarcinoma: A retrospective cohort study.

OBJECTIVE: To evaluate the interaction between extent of lymph node dissection (LND) and overall survival (OS) in patients with various histologic types of uterine cancer.

METHODS: We retrospectively identified 834 patients who had primary surgery in our institution for uterine carcinosarcoma (CS), papillary serous (UPSC) and endometrioid adenocarcinoma between 1984 and 2009. Stage, grade, total lymph node count (LNC), positive LNC, adjuvant therapy, age, race and OS were collected. OS was calculated using the Kaplan-Meier method. Predictive factors were compared with the log rank test and Cox regression analysis.

RESULTS: Our cohort included 158 patients with CS, 115 patients with UPSC and 561 patients with endometrioid adenocarcinoma. Of the cohort, 38% of the patients had Stage III or IV disease. LND was performed in 73% of patients with CS, 68% of patients with UPSC and 79% of patients with endometrioid adenocarcinoma. LND was performed in 82% of Stage I-II and in 68% of Stage III-IV cases. The median total LNC was 13 (range 1-75) and there was no significant difference in the total LNC between the different histologies. Median OS was 21 months for CS, 18 months for UPSC and 200 months for patients with endometrioid adenocarcinoma. A positive association between the total and positive LNC was present in all three histologic types (Spearman coefficient, p < 0.001). The cohort was divided in quartiles based on the total LNC and a Kaplan-Meier survival analysis was performed. A continuum of improved OS was noted in correlation with increased LNC. OS was 27 months for the group with 0 nodes, 112 months for the group with 1-8 nodes, 117 months for the group with 9-16 nodes and 196 months for the group with >17 nodes. Doubling the total LNC was associated with 28% risk of death reduction (HR 0.724, CI 0.66-0.794, p < 0.001) for the first year and 14% risk reduction (HR 0.858, CI 0.761-0.967, p = 0.012) for the second year.

CONCLUSIONS: In our cohort, the performance of LND is associated with improved OS. This effect appears to be uniform across pathology types. The extent of the LND is inversely correlated with the risk of death for the first 2 years.