Seattle Prostate Institute

Appointments 206.386.2356

About Prostate Cancer


Like most cancers, early detection is the key to curing prostate cancer. Fortunately, the Prostate Specific Antigen (PSA) blood test along with a yearly and digital rectal exam (DRE) can detect most cases at an early stage. In 2009, the American Urologic Society recommended PSA screening for men age 40 and over (previously they had recommended age 50). Although the American Cancer Society's recommendation is more complex, it generally recommends that screening begins at age 50. We feel that screening should begin by at least age 50 for men, and age 40 for those men who have significant risk factors including positive family history, or African-American race.


A PSA blood test and digital rectal exam (DRE) are the two standard screening tests for prostate cancer. PSA is an enzyme produced by the normal prostate but is elevated in most cases of prostate cancer. It is normal to have small amounts of this enzyme in the bloodstream, so an elevated PSA alone does not necessarily indicate cancer. It may indicate non-cancerous conditions such as prostate inflammation, infection, recent trauma, or benign prostatic hypertrophy. Often the DRE does not reveal any abnormalities that the doctor can feel. For this reason, the PSA blood test together with the DRE is important for early detection. Serial PSA measurements, rather than the absolute PSA value, also can provide a clue as to the source of an elevated PSA value.


A physician will evaluate these screening tests and may recommend a biopsy. The vast majority of physicians use an ultrasound guided technique to remove several small pieces of prostate tissue for microscopic examination. This is usually performed under local anesthesia in the urologist's office.

Gleason score

The biopsy will confirm the presence of cancer in the core specimens. Physicians describe the Gleason score, a system specific for describing the aggressiveness of prostate cancer. In this system, the microscopic appearance of the cancer is graded from 1-5, with a higher number denoting a more cancerous appearance and a lower number corresponding to tissue more representative of the normal prostate. The most common and the second most common grade are added together for the total Gleason Score. For example, if Gleason 3 was present in the majority of the cores with a small amount of Gleason 4 present, the Gleason Score would be 3+4=7. Generally speaking, and without consideration of other factors, Gleason 6 is characterized as low risk, 7 intermediate risk, and 8 or greater as high risk.

Treatment options are largely based on the result of this Gleason score in concert with the clinical stage (usually determined by the DRE), the PSA, and any urinary symptoms or other medical issues present.