Prognostic factors in endometrial clear cell carcinoma.

Objective: To document the experience regarding patients treated for endometrial clear cell carcinoma (ECCC), with reference to clinical, biochemical, histopathologic, and prognostic features.

Material And Methods: Twenty-six ECCC patients, diagnosed and treated between 2008 and 2014, were reviewed retrospectively. From the hospital records, all data related to patients' demographic, clinical, biochemical, and histopathologic assessments and adjuvant therapy adjustments were evaluated. Disease-free survival (DFS), overall survival (OS), and 5-year cumulative survival rates (CSR) were estimated as well as prognostic factors associated with OS.

Results: The median follow-up time was 22.7 months, and the mean age at diagnosis was 64.0 years. Fourteen (53.8 %) women had early stage and 12 (46.2 %) women had advanced-stage disease. There were 17 (65.3 %) patients with pure clear cell carcinoma and 8 (30.7 %) patients with mixed histology on the hysterectomy specimen. Extra-uterine disease occurred more frequently in patients with pure ECCC and elevated CA-125 concentrations. Seventeen (65.3 %) patients received adjuvant platinum and taxane chemotherapy with (n: 13/17, 76.4 %) or without radiotherapy in the form of external beam radiotherapy (ERT) and/or vaginal brachytherapy (BRT). The rest of the patients (n: 9/26, 34.6 %), who had tumor with no or limited myometrial invasion without LVSI, impaired general health status, and non-compliance-to-post-operative treatment proposal received no adjuvant therapy. The mean DFS and OS were 49.54 and 50.01 months, respectively, with the 5-year CSR of 46.4 %. The mean OS was significantly shorter in patients with higher pre-operative CA-125 values, >2 cm tumor diameter, myometrial invasion ≥1/2, cervical involvement, uterine serosal and/or adnexal invasion, lymph node metastasis, and, thus, with advanced-stage disease. Uterine serosal invasion was the only significant prognostic factor associated with OS in the multivariate analysis.

Conclusion: Increased pre-operative serum CA-125 levels are associated with advanced-stage disease, and uterine serosal involvement is a significant prognostic factor associated with OS in women with ECCC.