Biphasic Epithelial/Sarcomatous Renal Urothelial Tumors with Controversial Nomenclature: Case Report and Review of the Literature (original) (raw)

2023, MOH Journal of Medical Case Reports

Tumors that have only one typical cell morphology are known as monophasic tumors. In addition to the sarcomatous component, biphasic tumors have variable areas of two types of cells, typically gland-like epithelial structures and mesenchymal sarcomatoid elements. Sarcomatoid urothelial carcinoma (SUC) is an example of these biphasic tumors. Historically, these neoplasms have been assigned different names, including sarcomatoid carcinoma, carcinosarcoma, collision tumors, spindle cell carcinoma, myxoid sarcomatoid carcinoma, and metaplastic carcinoma. The World Health Organization (WHO) classification of urinary tract tumors, fifth edition, 2021, recognizes the controversy surrounding the nomenclature of this tumor; consequently, it uses the term "sarcomatoid carcinoma" to describe all these lesions and does not differentiate between sarcomatoid carcinoma (SC) and carcinosarcoma (CS). Patients are prone to misdiagnosis and missed diagnoses due to the nonspecific nature of these diseases' clinical manifestations, and the pathological stage is typically detected late. As a result, these patients' overall prognoses are poor. Despite the lack of specific treatment guidelines, surgery remains the treatment of choice in published reports for SUC. Because renal pelvis sarcomas are rare, when examining a renal pelvis tumor with spindle cell features, sarcomatoid carcinoma is the more likely diagnosis, not sarcoma. We report a case of a 55-year-old woman who presented with SUC involving the renal pelvis extending to the ureter and surrounding retroperitoneal area. We discuss and clarify the controversial nomenclature of this tumor and review the current literature.