Clear cell carcinoma of the endometrium. Prognosis and metastatic pattern.

BACKGROUND: To establish the prognosis, metastatic pattern, sites of treatment failure, and effect of various treatment modalities, a large series of patients with endometrial clear cell carcinomas (ECCC) was analyzed.
METHODS: Between 1970 and 1992, 181 patients with ECCC were treated. All pathologic slides and medical journals were reviewed. Clinical and histopathologic characteristics and type of treatment were analyzed with the univariate log rank test and multivariate Cox analysis.
RESULTS: The 5- and 10-year actuarial disease free survival rates were 43% and 39%, respectively. Pathologic stage, clinical stage, age, and myometrial invasion were the only significant prognostic variables in the univariate analysis. In the multivariate analysis, pathologic stage and age were the sole independent prognostic factors. Two-thirds of the patients with relapse relapsed outside the pelvis. The most frequent extrapelvic sites of relapse were the upper abdomen, lungs, and liver. Four of six patients treated with platinum-containing combination chemotherapy showed response, whereas none of the patients treated with single agent alkylating chemotherapy or progestagens responded.
CONCLUSIONS: Pathologic stage and age were the two most important prognostic factors in clear cell carcinoma of the endometrium. In Stage I disease, depth of myometrial invasion, age, and subtype of clear cell carcinoma were the sole independent prognostic factors. Two-thirds of the patients relapsed outside the pelvis.