Diagnosis and Staging
Early detection is the key to curing prostate cancer. We recommend that men over 50 have a yearly Prostate Specific Antigen (PSA) blood test and digital rectal exam (DRE). The risk of developing prostate cancer before age 50 is low, however we recommend that African-American men and men with a family history of the disease should begin yearly testing at age 40. Your physician can determine the best regimen for you.
PSA
A PSA (Prostate Specific Antigen) blood test and digital rectal exam (DRE) are the two standard screening tests for prostate cancer. PSA is an enzyme produced exclusively by the prostate. PSA is produced by both normal and prostate cancer cells. Small amounts of this enzyme in the bloodstream are normal and an elevated PSA alone does not necessarily indicate cancer. Normal levels are between 0-2.5 ng/ml. Levels higher than this should be evaluated. Benign elevations of PSA can be caused by an enlarged prostate, prostate inflammation, infection or trauma. Often, the DRE does not reveal any abnormalities that the doctor can feel. Occasionally, the PSA will be less than 2.5 ng/ml, but the DRE will be abnormal. For this reason, the PSA blood test together with the DRE is important for early detection. Almost all normal prostate cells and prostate cancer cells make PSA even if they are outside the gland. The PSA is used not only for detection but for monitoring results after treatment. If prostate cancer cells have spread to the bone or lymph nodes, these cells will make PSA. After surgery, the PSA is likely to drop quickly. After any form of radiation (Seeds, IMRT, etc.) the PSA drops more slowly as the cells die off over time. Thus, it may take several years to reach the lowest post-treatment PSA level (nadir) after any form of radiation treatment.
Biopsy
A transrectal biopsy using an ultrasound guided approach is the standard approach for biopsying the prostate. This is usually performed under local anesthesia in the urologist's office. The standard is 6-12 cores. The pathologist will grade the cancer using the Gleason Scoring system and likely will state how much of the core is involved with cancer. This percentage of the core involved with cancer is not used, typically, to influence treatment decisions. The number of cores involved, however, can influence the treatment recommendations.
Staging
Staging prostate cancer is based on the physical exam and any diagnostic studies performed. Since most patients do not require bone scans, CTs and other imaging tools, the digital rectal exam provides this staging information. If there is no palpable nodule in the gland, the Stage is T1. T1 means there is no palpable disease and is divided into 3 categories based on how it was diagnosed. T1a and T1b are reserved for patients in which the cancer was found after removing part of the gland to relieve blockage, called a TURP (transurethral resection of the prostate). T1c is usually detected by an elevated PSA. Note that even if the pathology shows disease on both sides of the gland, this does not affect the stage. Many patients and physicians get confused on this point and improperly label someone as stage T2c when biopsies are positive on both sides of the prostate, but no disease is palpable on the DRE; patients such as these are more properly defined as stage T1c.
T2a refers to a small nodule on one side of the gland, T2b means that the nodule occupies most of one lobe, and T2c means that the nodule occupies parts of both lobes. T3 is quite rare and means that the nodule extends outside the gland.
Risk Grouping
Every patient at PCTC is evaluated for Stage, Grade and PSA. Studies have demonstrated that patients can be grouped into risk groups that behave in similar ways. These risk groups can be useful for evaluating results of various treatments and to make treatment decisions. The risk groupings currently being adopted by most major centers are Low, Intermediate and High Risk. It is valuable for you to determine in which group you fall so that you can discuss it with your physician. Here are the risk groups most commonly used. See Understanding Risk Groups for a more complete description.
Low Risk
Stage T1 to T2b
PSA less than or equal to 10 ng/ml
Gleason Score 6 or less
Intermediate
PSA 10.1-20 or
Gleason score 7 or
Or Stage T2c only
Some patients are separated
into low intermediate and
high intermediate risk
Ask your physician
High
PSA > 20 or
T2c or
Gleason Score 8-10
Or 2 of the intermediate risk factors