Which is the most common site of carcinoma prostate?

85% of prostate carcinoma arise from the peripheral zone. Ninety five percent of tumors are adenocarcinoma. Prostate carcinoma rarely occur before the age of 40 years, and the incidence increases with age. PSA is elevated in 60% of men with prostate cancer. Levels above 4ng/ml is considered abnormal. Levels of PSA can be elevated with age and BPH. Falsely elevated PSA can be seen following cystoscopy, prostate biopsy, or urethral catheterization. PSA is not elevated following digital rectal examination. Ref: CURRENT Diagnosis & Treatment: Surgery, 13e, chapter 38