Is Omentectomy Necessary for Non-Endometrioid Endometrial Cancer.

BACKGROUND: In subtypes of non-endometrioid endometrium cancers (non-ECC), it is not clear whether the omentectomy is a part of debulking if visual assessment is normal. Recently, the ESMO-ESGO-ESTRO Endometrial Consensus Conference Working Group in their report titled "Endometrial Cancer: diagnosis, treatment and follow-up" recommended that omentectomy be performed in the serous subtype, but not in carcinosarcoma, undifferentiated endometrial carcinoma or clear cell. In this study, the question is whether omentectomy should be a part of a staging procedure in patients with non-ECC. Besides, the sensitivity and specificity of the visual assessment of omentum were analyzed.

METHODS: Patients diagnosed with non-ECC in 2 gynecological oncology clinics between 2005 and 2015 were retrospectively reviewed. Occult (absence of visible lesions) and gross (presence of visible lesions) omental metastasis rates of histological subtypes were analyzed.

RESULTS: We identified 218 patients with non-ECC. Thirty-four of them (15.1%) had omental metastases and 44.1% of these metastases (n = 15) were occult metastases. The sensitivity of the surgeon's visual assessment of an omentum (positive or negative) was 0.55. The highest rate of omental metastasis was found in carcinosarcoma followed by serous, mixed subtypes, and clear-cell (20.4, 17.3, 16.6, 10.0%, respectively). Adnexal metastasis was the only factor associated with occult omental metastasis (p = 0.003).

CONCLUSION: Omental metastases occur too often to omit omentectomy during surgical procedures for non-ECC regardless of histological subtypes, and visual assessment is insufficient in recognizing the often occult metastases. Omentectomy should be a part of the staging surgery in patients with non-ECC.