Diagnostic utility of [alpha]-methylacyl CoA racemase (P504S) and HMWCK
in morphologically difficult prostate cancer.
66-69) When a predominantly spindle cell lesion with limited tissue availability is encountered in the bladder, an immunohistochemical panel composed of ALK-1, SMA, desmin, cytokeratin (AE1/AE3), p63, and HMWCK or CK5/6 is potentially helpful (Table 5).
Inflammatory myofibroblastic tumor is negative for p63, HMWCK, and CK5/6 by immunostain.
Permanent sections and immunohistochemical profile with positive immunoreactivity for HMWCK
, vimentin and CD-99 as well as negative immunostaining for LCA, desmin, NSE, and chromogranin allowed the pathologist to distinguish the PNET from other small round cell tumors (figure 1).
A useful panel for this distinction is CD10, CK7, RCC marker, mesothelin and HMWCK
(clone 34 E12).
In the assessment of atypical papillary lesions (ADH/DCIS involving benign intraductal papilloma or papillary DCIS), immunohistochemical evaluation of the expression of HMWCK is a valuable adjunct, in which benign papillary lesions exhibit strong, mosaic reactivity throughout the lesion in 88% to 100% of cases, and atypical papillary lesions are nonreactive, indicating a clonal proliferation of luminal epithelial cells in 80% to 100% of cases.
Abbreviations: ADH, atypical ductal hyperplasia; CK, cytokeratin; DCIS, ductal carcinoma in situ; HMWCK, high-molecular-weight cytokeratin; MEC, myoepithelial cells; SMMHC, smooth muscle myosin heavy chain.
In a feasibility study, a triple-antibody cocktail consisting of MMp40, mouse monoclonal HMWCK
(34[beta]E12), and rabbit monoclonal AMACR was diluted and optimized in a modified phosphate-buffered saline diluent, followed by a cocktail of goat anti-mouse horseradish-peroxidase polymer enzyme and a goat anti-rabbit alkaline phosphatase polymer enzyme polymer.
9) Immunohistochemically, the atypical acini show strong, diffuse nuclear p63 expression in the secretory cells (non-basal cell distribution) (Figure 1, F), positive AMACR and PSA expression, and no expression with HMWCK
They usually stain for basal cell markers such as HMWCK
Immunohistochemical Profile of Common Renal Neoplasms Clear cell RCC Positive for vimentin, AE1/AE3, CD10, RCCM, PAX2, PAX8, and CAIX Negative for HMWCK
, CK7, CK20, CD117, kidney-specific cadherin, and parvalbumin Papillary RCC and mucinous tubular and spindle cell carcinoma Positive for vimentin, AE1/AE3, CK7, AMACR, RCCM, PAX2, and PAX8 Negative for CD117, kidney-specific cadherin, and parvalbumin Chromophobe RCC/oncocytoma Positive for E-cadherin, kidney-specific cadherin, parvalbumin, CD117, AE1/AE3, CK7 strong/diffuse for chromophobe RCC Negative for vimentin, CK7 (or weak for oncocytoma), CAIX, and AMACR Collecting duct carcinoma Positive for p63 and HMWCK
; some are positive for PAX2 and PAX8 Negative for RCCM, CD10, CD117, kidney-specific cadherin, and parvalbumin Xp11.
Extended Special Other Stains Immunohistochemistry Findings Mucicarmine, PAS HMWCK
-; desmin, EM rare +, colloidal S100, vimentin - Fe + NA NA Cytology NA NA EM, cytology Mucicarmine, PAS Vimentin +; Ulex EM -, Alcian blue +w +; AFP, CEA - PAS/PAS-D -, Desmin, CEA, NA colloidal Fe - vimentin -; EMA +f NA Vimentin + NA NA Vimentin + NA NA NA NA NA NA NA NA NA NA NA NA NA NA Vimentin +, LCA - Cytology, EM