Diagnosis of prostate cancer is made by biopsy and histological examination of the biopsy specimen by a pathologist. Procedures like PSA (prostate specific antigen) blood test and DRE (Digital rectal examination), used in screening are not sufficient for making a diagnosis of cancer of the prostate. Screening procedures help only in identifying persons who might be suffering from cancer of the prostate.
Biopsy
Cancer of the prostate, unlike breast cancer, which starts as a single tumor and grows outwards, starts as multiple small tumors at different locations within the prostate gland. Therefore during biopsy samples are collected from different locations in the prostate gland. This is referred to as multiple core biopsy. A minimum of six cores are usually recommended in cancer of the prostate.
Patients suffering from prostatitis (infection of prostate) are advised not to undergo biopsy until a course of antibiotics is completed, to cure the infection. Patients with persistent high PSA levels but negative biopsies are advised to undergo a repeat biopsy.
During biopsy a needle is inserted into the tumor through the perineum, under the guidance of ultrasound, and cell specimens are taken from different locations within the prostate gland. After the biopsy the samples are examined by the pathologist under the microscope to look for cancer cells.
