CASE OF THE WEEK
Editors: Francesca Khani (Frk9007@med.cornell.edu) and Mahmut Akgul (akgulm@amc.edu)
2021-49/December 6
Contributors: Maria Estela Pompeu do Amaral, Daniel Athanazio
A man in his 80s reported hematuria during preoperative period before prostatectomy due to prostate cancer. A 1.9 cm exophytic tumor was detected in bladder dome at cystoscopy. A multidisciplinary team opted for radical prostatectomy and partial cystectomy. The radical prostatectomy specimen showed a prostatic acinar adenocarcinoma Gleason score 4+3=7 (Grade Group 3 with cribriform morphology), pT3a. Images from the partial cystectomy are shown below.
Quiz
1. What is the correct diagnosis?
a) Metastatic prostate adenocarcinoma
b) Urothelial carcinoma with clear cell morphology
c) Mullerian-type clear cell adenocarcinoma
d) Collision tumor: urothelial carcinoma and metastatic renal cell carcinoma
e) Urothelial carcinoma with lipid-rich morphology
1. b
Urothelial carcinoma with clear cell morphology
The tumor in bladder dome was completely unrelated to prostate adenocarcinoma. There were three small foci of lamina propria invasion (maximum 0.6 mm deep) with no variant morphology. The exophytic mass showed a clear transition between a conventional papillary component (see Figures 2 and 3A) and area of papillary and solid clear cell morphology (Figure 3B and 4). Adjacent mucosa showed multifocal areas of urothelial carcinoma in situ.
Tumor cells showed multifocal expression prostein/P501S in a granular cytoplasmatic distribution, which mirrors the staining pattern in prostate benign epithelium and prostatic adenocarcinoma. In addition, PSA, PSMA and NKX3.1 were negative in the entire bladder tumor. Cytokeratin 7 was strongly and diffusely positive in all tumor areas. GATA3 was strongly expressed in conventional papillary areas and only focally positive in clear cell areas. P63, napsin A and PAX8 were negative in all tumor areas. The clear cell component stained strongly with PAS stain but not with PAS diastase further supporting the presence of glycogenic-rich content.
Aberrant prostein/P501S expression is rare in urothelial carcinoma. In a series of 132 cases, no expression prostein/P501S was observed. (1) In other series of 138 cases, the expression of PSA, PSMA and prostein/P501S in urothelial carcinoma was 9%, 0.7% and 0.7%, respectively. (2) Isolated expression of prostein/P501S in urothelial carcinomas should not be interpreted as evidence of a prostate primary tumor.
Clear cell morphology has no clear-cut prognostic implication in urothelial carcinoma with some preliminary data suggesting a more aggressive behavior. (3,4) Its proper recognition is important to avoid misinterpretation as other lesions.
1. Srinivasan M, Parwani AV. Diagnostic utility of p63/P501S double sequential immunohistochemical staining in differentiating urothelial carcinoma from prostate carcinoma. Diagn Pathol. 2011 Jul 21;6:67.
2. Oh WJ, Chung AM, Kim JS, Han JH, Hong SH, Lee JY, Choi YJ. Differential Immunohistochemical Profiles for Distinguishing Prostate Carcinoma and Urothelial Carcinoma. J Pathol Transl Med. 2016 Sep;50(5):345-54.
3. Lopez-Beltran A, Henriques V, Montironi R, Cimadamore A, Raspollini MR, Cheng L. Variants and new entities of bladder cancer. Histopathology. 2019 Jan;74(1):77-96.
4. Alderson M, Grivas P, Milowsky MI, Wobker SE. Histologic Variants of Urothelial Carcinoma: Morphology, Molecular Features and Clinical Implications. Bladder Cancer 6 (2020) 107–122.
Maria Estela Pompeu do Amaral and Daniel Athanazio
Imagepat, Laboratory of Pathology
Salvador, Bahia, Brazil
Urinary bladder
Urinary Bladder; Neoplasms Urinary Bladder; Glycogen; Prostein