Immunohistochemical Analysis of Prostein in Needle Core Biopsies of Acinar and Intraductal Prostatic Adenocarcinoma in Western Kenya Population

Abstract

Background: Prostein is a newly reported prostate cancer biomarker. Nonetheless, no reports on African population are available. The current study aimed to determine the prostein expression in archived prostatic core biopsies in Western Kenya. Methods: This was a retrospective study conducted on malignant and benign prostatic tissue core biopsies of 106 patients from Jaramogi Oginga Odinga Teaching and Referral Hospital and division of urology at Synergy Clinics, Kisumu between January 2018 to May 2021. Manual Immunohistochemical technique was performed on each of the 106 samples and on the following non-prostatic male control biopsies; Testis, Penis, Liver and Esophagus. Cellular location of prostein staining was evaluated microscopically and classified as cytoplasmic or nucleocytoplasmic. Intensity of prostein expression was assessed and graded according the immunohistochemistry composite score. Results: The mean (SE) age was 72.00 ± 0.93 years. 97.2% of malignant and all the benign prostate tissue stained positive for prostein whereas the four non-prostatic male tissues were negative. Staining intensities were weak (24.5%), Moderate (17.0%), strong (55.7%) and non-stained (2.8%). The staining was highly immunolocalized within the cytoplasm (95.1% cases) as compared to nucleocytoplasmic (2.0% cases). The mean immunoreactivity composite score was 1.91 ± 0.96 (0.0-3.14). Strongly stained sections of both acinar and intraductal adenocarcinoma had a staining pattern clustered within the cytoplasm in a perinuclear location whereas the weakly stained sections had less coarse brown cytoplasmic granular appearing. Conclusion: Prostein is expressed in both acinar and intraductal adenocarcinoma and can be routinely used in differential diagnosis of prostate cancer even in remote settings.