[Endometrioid carcinoma with sex cord-like formations and hyalinization of the uterine corpus: a clinicopathologic analysis of 5 cases].

OBJECTIVE: Endometrioid carcinoma with sex cord-like formations and hyalinization of the uterine corpus is a rare morphological variant of endometrioid carcinoma. The biphasic morphological features may cause confusion with carcinosarcoma of the uterus, leading to misdiagnosis. The aim of this article is to elucidate the clinicopathological characteristics of such endometrial carcinoma to avoid misdiagnosis.

METHODS: The clinical and pathological data of 5 cases of endometrioid carcinoma with sex cord-like formations and hyalinization of the uterine corpus were collected and analyzed.

RESULTS: The age of the 5 patients ranged from 29 to 39 years, with a mean age of 33 years. Four patients underwent surgery of radical hysterectomy, the other dilation and curettage biopsy. Among the former, 3 patients were at FIGO stageⅠA, the other ⅢC1. Microscopically, all 5 tumors contained endometrioid carcinoma components, 4 of which were FIGO gradeⅠ, the remaining one was grade Ⅱ. Each tumor was of variable proportions of corded and hyalinized areas ranging from 10% to 60%. The cells in the corded and hyalinized areas were epithelioid, fusiform and spindle in morphology, admixed with the endometrioid carcinoma component, resulting in a biphasic pattern. The corded and hyalinized component exhibited distinctively different immunophenotypical feature from that by the conventional endometrioid carcinoma component. The results of follow-up for 4 patients of 7 to 68 months (mean=26.5 months) revealed that all patients were alive without recurrence of the malignancy.

CONCLUSIONS: Endometrioid carcinoma with sex cord-like formations and hyalinization of the uterine corpus presents unique morphology, and the patients are usually young with relatively favorable prognosis. The definite mechanism for the pathogenesis of the sex cord-like formations and hyalinization needs further investigation.