Prostate cancer, in general, refers to adenocarcinoma. Rarely prostate can have other rare forms of cancers includes sarcoma.
Adenocarcinoma of prostate is generally graded using a system called Gleason grade. The pathologist takes into consideration the appearance of the cancer cells and the surrounding tissue as seen under a low power microscope to give a grade to the cancer.
In general the grades given are from 2 – 5. For prostate biopsy showing cancer, the minimum grade given is 3. Gleason 2 grade at times is given for TURP specimen. Gleason 4 and 5 are generally deemed high grade cancer.
As prostate cancer is known to have different grades of cancer within the same prostate, a system of scoring has been devised.Gleason score will have the most common grade + next most common grade. The scores and their inferences are as follows