Urinary bladder urothelial carcinoma with concurrent plasmacytoid and micropapillary differentiations: A report of two cases with an emphasis on serum carbohydrate antigen 19‐9

Abstract

We report two cases of urinary bladder urothelial carcinoma (UC). In both, histological examination of a transurethral resection specimen of the bladder tumor revealed UC with plasmacytoid and micropapillary differentiations. In Case 1, residual plasmacytoid UC deeply invaded the extravesical fat tissue of the radical cystectomy specimen, and metastatic carcinoma was found in almost all the dissected lymph nodes. Despite adjuvant chemotherapy and radiotherapy, the patient died 25 months postdiagnosis. Elevated serum carbohydrate antigen 19-9 (CA19-9) returned to near normal levels after radical cystectomy, but they increased shortly before death. In Case 2, no residual carcinoma was found in the radical cystectomy specimen or lymph nodes. Postoperative serum CA19-9 was maintained at normal levels, and the patient remains alive without recurrence or metastasis. Although plasmacytoid and micropapillary UC are known aggressive variants of UC, plasmacytoid UC may be more aggressive. Serum CA19-9 could serve as a useful biomarker to monitor progression of plasmacytoid UC.

HER2 Protein Overexpression and Gene Amplification in Plasmacytoid Urothelial Carcinoma of the Urinary Bladder

“…CD138 is known to be a marker for plasma cells, and variable expression of CD138 in plasmacytoid urothelial carcinoma has been reported in previous studies [ 5 , 6 , 10 , 25 ]. CD138 is also expressed in urothelial carcinoma in situ , conventional urothelial carcinoma, and even normal urothelium [ 29 , 30 ].…”

“…Little is known about the HER2 status in plasmacytoid urothelial carcinoma. Only one case report showed HER2 protein expression by IHC in two plasmacytoid urothelial carcinoma cases, of which one case was HER2 IHC 3+ and the other one 2+ [ 25 ]. There has been no study about HER2 gene amplification in plasmacytoid urothelial carcinoma.…”

“…However, little is known about HER2 expression and gene amplification in plasmacytoid urothelial carcinoma. Only one study showed HER2 protein overexpression in 2 cases of plasmacytoid urothelial carcinoma with concurrent micropapillary component [ 25 ].…”

Metastatic Plasmacytoid Bladder Cancer Harboring a CDH-1 Mutation and Producing High Levels of CA 19-9. A Case Report and Literature Review

“…Other mutations that are common in UC were also described in PUC [ 7 , 8 ]. In terms of tumor markers, few reports showed that PUC could produce carbohydrate antigen (CA) 19-9 [ 9 , 10 ]. Herein, we report a patient with CDH-1 mutated PUC who presented with disseminated peritoneal metastasis and had high levels of CA 19-9.…”

Lipid Cell and Micropapillary Variants of Urothelial Carcinoma of the Ureter

“…Interestingly, HER2 was overexpressed in both lipid cell and micropapillary variants of UC compared to most regions of conventional UC, where HER2 expression was weak and incomplete. Micropapillary UC is characterized at the molecular level by frequent overexpression, gene amplification, and/or somatic mutation of HER2 [ 12 , 13 , 14 , 15 ]. De Giorgi et al [ 9 ] have also reported on a case involving HER2 overexpression in the lipid cell variant of UC.…”