title: Immunohistochemical detection of P504S in primary and metastatic renal cell carcinomas.
abstract: P504S/alpha-methylacryl CoA racemase has been shown to be a relatively sensitive and specific positive marker for prostatic adenocarcinoma. The potential utility of P504S in renal cell neoplasms has not been explored in a large series. We assessed the diagnostic value of P504S in 332 cases of nonprostatic neoplasms using the avidin-biotin-peroxidase complex technique, including 115 renal neoplasms, 28 metastatic renal cell carcinomas (RCCs), and 189 nonrenal neoplasms. The results demonstrated that a granular, cytoplasmic staining pattern for P504S was observed in 48 of 70 (68.6%) conventional (clear cell) RCCs, 15 of 15 (100%) papillary RCCs, 2 of 7 (29%) chromophobe RCCs, and 2 of 8 (25%) oncocytomas. Among the 70 cases of clear cell RCC, positivity of P504S was seen in 40%, 71%, 94%, and 75% of RCCs with Furhman nuclear grade I, II, III, and IV, respectively. Strong immunostaining was present in each case (86/86) in the proximal tubules adjacent to the renal neoplasm. Eighty-two percent of metastatic RCCs (23/28) were positive for P504S. However, only 24 of 189 (13%) nonrenal malignancies were positive. The 24 positive cases included 12 of 13 (92%) colorectal adenocarcinomas, 6 of 30 (20%) ductal carcinomas of the breast, and 4 of 23 (17%) adenocarcinomas of the lung. These findings suggest that P504S is a useful marker in diagnosing primary and metastatic RCCs, although it has little value in differentiating chromophobe RCC from oncocytoma.
authors.affiliation: Department of Laboratory Medicine, Geisinger Medical Center, Danville, PA 17822, USA. Flin1@geisinger.edu
authors.forename: Fan
authors.initials: F
authors.lastname: Lin
authors.forename: Robert E
authors.initials: RE
authors.lastname: Brown
authors.forename: Ting
authors.initials: T
authors.lastname: Shen
authors.forename: Ximing J
authors.initials: XJ
authors.lastname: Yang
authors.forename: Conrad
authors.initials: C
authors.lastname: Schuerch
mesh_terms: D000951:Antigens, Neoplasm / Q000032:analysis*; D014408:Biomarkers, Tumor / Q000032:analysis / Q000592:standards; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis / Q000556:secondary; D002292:Carcinoma, Renal Cell / Q000175:diagnosis / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000556:secondary; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000175:diagnosis / Q000556:secondary; D008297:Male; D009362:Neoplasm Metastasis / Q000175:diagnosis / Q000473:pathology; D019998:Racemases and Epimerases / Q000032:analysis*; D012680:Sensitivity and Specificity
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D019998:Racemases and Epimerases; C108352:alpha-methylacyl-CoA racemase