Investigation of Extra-Uterine Tumor Dissemination of Endometrial Cancers with Myometrial Invasion Less Than 50% According to Histologic Subtypes.

Objectives: This study aims to investigate the rates of extra-uterine metastases of non-endometrioid endometrial tumors limited to the half of the myometrium.

Methods: Patients operated for endometrial cancer between 2005-2015 in two gynecologic oncology centers were screened from clinical archives. The inclusion criteria were serous, clear cell, undifferentiated or carcinosarcoma histologies and less than half myometrial invasion. Each histological type was analyzed for adnexal metastasis, lymph node metastasis (pelvic/paraaortic) and omental metastasis.

Results: A total of 116 patients with the median age of 64 (34-72) were examined. Of the patients, 57 were serous (49.1%), 29 were clear cell (25.0%), 27 were carcinosarcoma (23.3%) and 3 (2.6%) were undifferentiated histologic type. Adnexal metastasis (over/tuba) was detected in 15 patients (12.9 %), nodal metastasis in 10 patients (8.6%), and omental metastasis in 15 patients (12.9%). The rates of adnexal metastases were calculated as 14% for serous type, 10% for clear cell type and 11% for carcinosarcoma. Omental metastasis rates were 11% for serous type, 17% for clear cell type and 15% for carcinosarcoma. The rates of extra-peritoneal nodal metastases were calculated as 12% for serous type, 7% for clear cell type and 4% for carcinosarcoma.

Conclusion: According to the findings obtained in this study, the rates of extra-uterine metastasis are high for serous, clear cell or carcinosarcoma types even in the early period. However, the lymph node metastasis in the carcinosarcoma seems to be lower. A comprehensive staging surgery should be planned for these patients, regardless of the depth of myometrial invasion.