Prostate-Specific Antigen, High-Molecular-Weight Cytokeratin (Clone 34βE12), and/or p63

Abstract

An optimal immunohistochemical panel to distinguish poorly differentiated prostate (PCa) from urothelial (UCa) carcinoma was selected from a panel consisting of prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP), high-molecular-weight cytokeratin (HMWCK), clone 34betaE12, cytokeratin (CK) 7, CK20, p63, and alpha-methylacyl-coenzyme A racemase. The pilot group was composed of poorly differentiated UCa (n = 36) and PCa (n = 42). PSA and PAP stained 95% of PCa vs 0% and 11% of UCa cases, respectively. HMWCK and p63 stained 97% and 92% of UCa vs 2% and 0% of PCa cases respectively. CK7/CK20 coexpression was noted in 50% of UCa cases, whereas 86% of PCa cases were negative with both. A panel of PSA, HMWCK, and p63 was optimal for separating 95% PCa (PSA+/HMWCK and/or p63-) vs 97% UCa (PSA-/HMWCK and/or p63+). This panel was used on 26 diagnostically challenging cases and resolved 81% of cases as UCa vs PCa. The majority of PCa cases retain PSA. Negative PSA with positive HMWCK and/or p63 establishes a diagnosis of UCa.

Diagnostic utility of p63/P501S double sequential immunohistochemical staining in differentiating urothelial carcinoma from prostate carcinoma

“…Of the 13 UC cases that were negative for p63, 3 cases had micropapillary features. Our results are comparable to Kunju et al [15] who also found diffuse nuclear p63 positivity in 92% of their UC cases using the same p63 monoclonal antibody. Chuang et al [3] using the same p63 antibody found p63 in 83% of their UC cases.…”

“…Although the diagnostic utility of p63 and P501S in distinguishing between primary PC and UC have been individually evaluated previously [3,11,15], thus far, there have been no previous studies evaluating these two markers together either as a cocktail or applied sequentially. Our results indicate that dual-color immunohistochemistry with p63 and P501S applied sequentially shows excellent specificity for distinguishing UC from PC.…”

“…Caution should be exercised in interpreting a p63-/P501S- profile as lack of p63expression does not rule out UC. Kunju et al [15] using a panel comprising PSA, HMWCK, and p63 to distinguish between PC and UC in 26 diagnostically challenging cases found p63 positivity in 10/13 UCs. The 3 remaining p63 negative UCs were also negative for HMWCK, and they established the urothelial origin using CK 7 and CK 20 expression.…”

Comparison of Immunohistochemistry Expression of CK7, HMWK and PSA in High-Grade Prostatic Adenocarcinoma and Bladder Transitional Cell Carcinoma

“…One of the most suitable methods for differentiation is the use of immunohistochemistry (IHC) because many immunohistochemistry markers are different in these two tumors (9,10). Prostate-specific antigen (PSA) is an appropriate marker for PCa, and Cytokeratin 7 (CK7) and high-molecular-weight cytokeratin (HMWK) clone 34β£12 are suitable markers for bladder carcinoma (11), and their combination can play a significant role in differentiating these cancers (12,13). Two prostatic Vol.…”

“…Rectum adenocarcinoma, urothelial carcinoma, or bladder adenocarcinoma cannot produce PSA (22). The 34β£12 or HMWK antibody is a nonsensitive but highly specific marker for differentiating the transitional bladder carcinoma from prostate adenocarcinoma (11,23). The 34β£12 antibody specifically detects the basal cells.…”