Prostatic sarcomatoid carcinoma in a dog: cytologic and immunohistochemical findings.
An 8-year-old neutered male Boxer was presented with tenesmus, hemorrhagic urethral discharge, and dysuria. Abdominal ultrasound and radiographic examinations revealed irregular prostatic enlargement. Laparotomy was performed and intraoperative cytology was done on imprint smears of a biopsy specimen obtained from a prostatic mass. The cytologic preparation was highly cellular and contained a predominant population of atypical, large, loosely cohesive spindle cells, with rare multinucleated cells and mitotic figures. The cytologic findings were consistent with undifferentiated sarcoma. At necropsy, a large cystic prostatic mass and numerous satellite nodules in the soft tissues around the pelvis were found. On histologic examination the tumor was composed primarily of bundles of neoplastic spindle cells. Rare pseudo-acinar structures and signet-ring cells also were observed. On immunohistochemical examination, the neoplastic cells co-expressed cytokeratin and vimentin. Based on histologic and immunohistochemical findings, the tumor was diagnosed as primary prostatic sarcomatoid carcinoma. This is a rare tumor in dogs, in which biphasic morphology of epithelial and mesenchymal cells can complicate the diagnosis, requiring immunochemical stains for confirmation.
Departimento di Patologia Animale, Igiene e Sanità Pubblica Veterinaria, Sezione di Anatomia Patologica Veterinaria e Patologia Aviare, Università degli Studi di Milano, Milan, Italy. maria.pintodacunha@unimi.it
Nazarél
N
Pinto da Cunha
Gabriele
G
Ghisleni
Stefano
S
Romussi
Mario
M
Caniatti
D000818:Animals; D002277:Carcinoma / Q000145:classification / Q000473:pathology / Q000662:veterinary*; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D008297:Male; D011471:Prostatic Neoplasms / Q000473:pathology / Q000662:veterinary*; D012509:Sarcoma / Q000145:classification / Q000473:pathology / Q000662:veterinary*