Squamous papillary carcinoma with transitional differenciation of the endometrium: an uncommon condition

A 62 year old woman presented with post-menopausal bleeding occurring at least for three months. The patient underwent an echography which showed a multiple myomatous uterus with enhanced thickening of the endometrium uper than 20mm.After hysterectomy, gross examination showed a myomatous uterine-body lined in some places by a friable thickened process(arrow-a) distant of the cervix. Histological examination found, in addition to interstitial myomas, a process consisted of papillary structures with fibro vascular cores covered by several cell layers with large amounts of cytoplasm and pleomorphic hyper chromatic nuclei (b-c).Nucleoli was inconspicuous. The invasive front of the tumor was of the pushing type, and the deeply located neoplastic cells were ovoid with a pale eosinophilic cytoplasm, resembling urothelial cells (d) these cells represented 15% of the total tumor volume. No glandular endometrioid component was found: A diagnosis of papillary squamous cell carcinoma with foci of transitional cell differenciation was made. The tumor did not reach the cervix or the adnexa which were entirely examined microscopically. Transitional cell differenciation in endometrial carcinomas is extremely uncommon, with fewer than 15 cases reported. Lower transitional cell differenciation qualifies the tumor as a mixed carcinoma with transitional cell differenciation. A pure transitional cell carcinoma of the endometrium is a carcinoma in which 90% of more of the neoplastic cells resemble the urothelial transitional cells: an uncommon condition with seventy cases reported.