Immunohistochemical profile of ductal adenocarcinoma of the prostate

Abstract

Ductal adenocarcinoma (DAC) is considered an aggressive subtype of prostate cancer with greater risk of progression than acinar adenocarcinoma (AC). It has been debated whether DAC is a distinct subtype or not. Our aim was to examine the protein expression of DAC and compare the results with AC. A tissue microarray was constructed from 60 DAC and 46 AC matched by Gleason score and stained for 28 immunomarkers (hormonal receptors, prostate specific markers, cell cycle related markers, oncogenes and molecular biomarkers). HMWCK was positive in 8.5% of DAC, but negative in AC (p = 0.045). p16 was positive in 53.3% of DAC and 26.1% of AC (p = 0.005). p53 was positive in 42.4% of DAC and 26.7% of AC (p = 0.031). A distinct patchy positivity of CK20 was seen in 23.7% of DAC and 9.1% of AC (p = 0.047). Villin was positive in 3.4% of DAC while negative in AC. Ki-67 labeling index was higher in DAC than in AC [mean 9.2% (95% CI 6.4-12.0) and 2.6% (1.9-3.4), p