Plasmacytoid variant of urothelial carcinoma: Diagnostic challenges and role of immunohistochemistry

Abstract

Plasmacytoid carcinoma of the urinary bladder or plasmacytoid urothelial carcinoma (PUC) is rare and only recently described a histological variant of transitional cell carcinoma. The morphological resemblance of PUC to other malignancies is a source of diagnostic dilemmas and often misdiagnosis. Immunohistochemistry plays a pivotal role in narrowing the differential diagnosis and reaching to a conclusive diagnosis. A diagnosis of PUC usually carries a dismal prognosis. Hence, correct diagnosis is important. We report here a 52-year-old male with a plasmacytoid variant of urothelial carcinoma.

Plasmacytoid urothelial carcinoma of renal pelvis with positive zinc finger E–box–binding homeobox 1: a case report

“…Second, CD38 is an appropriate immunohistochemical marker for confirming a plasmacytoid transformation in a urothelial carcinoma. Several studies have shown that the plasmacytoid tumor cells of a urothelial carcinoma are immunoreactive for CD138 [ 3 – 6 ]. CD138 is a highly sensitive and specific marker for normal and neoplastic plasma cells [ 15 ].…”

“…Plasmacytoid urothelial carcinoma, which is a characteristic morphology similar to plasma cells, is an unusual variant that is included in the World Health Organization classification of urothelial neoplasms [ 1 , 2 ]. Several studies have recently reported that the plasmacytoid component of a urothelial carcinoma exhibits positive staining for CD138, an immunohistochemical marker for plasma cells, in addition to showing a morphological similarity [ 3 – 6 ]. A plasmacytoid urothelial carcinoma is an aggressive subtype associated with a poor prognosis even if the plasmacytoid component is locally limited [ 7 ].…”