Abstract
Carcinosarcomas (CSs) are rare biphasic neoplasms of the female genital tract. The occurrence of non-epithelial or non-mesenchymal differentiations in CSc is extremely rare.
A case of a 54-year-old woman with a uterine tumor showing histological, immunohistochemical, and ultrastructural features of CS with melanocytic differentiation. It was a 7.0x5.6 cm polypoid tumor arising from endometrium and metastasizing in the abdominal cavity as a malignant melanoma - the most aggressive component of CS.
Despite adjuvant chemotherapy, she died 8 months after diagnosis due to the metastatic spread of CS. In line with current knowledge, we assess the melanocytic differentiation as one of differentiation line with the ability of multidirectional stem cell differentiation.
We discuss possible pathogenesis of this lesion and the role of tamoxifen in its development. To the best of our knowledge, only one case of uterine CS with melanocytic differentiation has been reported in the English literature.