Carcinosarcoma of the uterus with extensive neuroectodermal differentiation

A case of uterine carcinosarcoma with extensive neuroectodermal differentiation occurring in a 54‐year‐old woman is described. Microscopically, the endometrial tumour was predominantly composed of a sheet‐like proliferation of small‐ and medium‐sized cells. These cells were characterized by fibrillary cytoplasmic processes, rosette‐like formations, perivascular palisading patterns, and immunoreactivity for glial fibrillary acidic protein, synaptophysin, leu 7 and neuron‐specific enolase. In limited areas, features of conventional carcinosarcoma, including squamous cell carcinoma, leiomyosarcoma and islands of the above mentioned small‐to medium‐sized cells that were intermingled, were observed. The tumour was aneuploid by flow cytometry. The patient is alive with tumour for three months. It is suggested that at least some cases of uterine primitive neuroectodermal tumour may be explained by one‐sided neuroectodermal development within a carcinosarcoma.