Background: The diagnosis of prostatic pathology may be of challenging , as some  difficult and suspected, atypical  cases may lack basal cell layer by routine H&E sections . Antibodies against 34BE12(HMW-CK) and p63 aid the diagnosis of such cases , to distinguish benign from  malignant prostatic lesions.

Objective: to identify basal cells in atypical prostatic lesions ,and distinguish benign from malignant prostatic lesions.

Type of the study:  A retro-spective  study.

Methods:  115cases of  paraffin embedded prostatic tissue blocks ,diagnosed as : 76 cases were benign prostatic hyperplasia( BPH) , 9 cases were  high grade –prostatic intraepithelial neoplasia (HG-PIN) , and 30 cases were prostatic carcinoma(PCa) .Sections from each blocks were prepared for immunostaining with 34BE12 and p63.

Results : basal cells were detected in cases of BPH , and HG-PIN , and absent  in all cases of prostatic carcinoma ,using basal cell markers . Negative benign glands(>2) were found in 71.6% and 38.2%  for   BPH  and 57.1% and 55.6% for HG-PIN immunostained  with high molecular weight cytokeratin (34BE12) and p63 , respectively, and significantly reduced to 9.0% and 11.1% for BPH and HG-PIN, respectively  with combined using of both markers .Conclusion : Combination of both   basal cell markers (34BE12 , p63) improving basal cell detection in atypical ,suspected prostatic lesions and distinguish benign from malignant lesions.