Prostate Cancer is diagnosed with biopsy of the prostate.
Typically a biopsy is performed with a transrectal ultrasound guided approach (TRUS bx). The main potential complications from a prostate biopsy include
- Blood in the urine,
- Blood in the semen,
- Infection in the prostate or urinary tract,
- Rectal bleeding.
Antibiotics for prostate biopsy. Antibiotics are typically prescribed prior to a prostate biopsy in order to reduce the risk of an infectious complication. The most common antibiotic utilized is a Flouroquinolone (Ciproflozacin, Levofloxacin etc); however, we and others have documented an emergence of Quinolone resistant bacteria.
Of course, diagnosing cancer in time to treat it effectively is crucial. But the issue is complicated by the fact that all prostate cancers are not created equal. Some are very slow-growing, and never need treatment; others can be fatal within a matter of months after they are diagnosed. For me, just as important as finding cancer early, is knowing which kind of cancer – the “good” or the “bad” — we’re dealing with.
In one study, comparing blood samples of men who developed prostate cancer 15 years before diagnosis with those who did not, we have established the safe rate at which PSA can change every year in men, and have determined that – many years before a tumor may be otherwise detectable – “free” PSA may be an excellent predictor of aggressive cancers that will need to be treated. (In the bloodstream, some PSA molecules are glued, or “bound” to certain inhibitors that prevent the PSA from breaking down protein; other molecules, however, are unfettered – they’re “free”). .
Prostate biopsies do not cause cancer to spread. Thus, you can safely “take the next step” if your doctor recommends a biopsy. A typical biopsy samples the right and left side of the prostate 6 times. Once the biopsy tissue is obtained, the next step is for a pathologist to examine it under the microscope. To diagnose prostate cancer, pathologists typically first examine the biopsy for abnormal, cancerous cells. Cancer cells look different than normal prostate cells and an experienced pathologist can very reliably make this diagnosis. If the pathologist sees cancer, the next step is to determine its aggressiveness. This is based on the extent of the cancer (how many biopsy cores contain cancer) and the grade of the cancer (how aggressive each cell looks under the microscope).
Some urologist are now using MRIs of the prostate to help them direct the needle into suspicious areas of the prostate. This may be helpful in your case. Ask your urologist if he/she thinks a MRI guided biopsy is necessary.
What is Gleason Grading?
As normal prostate cells change to tumor cells, they have different appearances under the microscope. Today, prostate cancers are given a score or grade, which we call the Gleason Grade. The modern Gleason grading system scores cancers with a 3, 4 or 5. The pathologist first scores the most common/prevalent type of cancer that he sees under the microscope. Then he looks for the next most common type. Together this score is the Gleason sum.
For example, if a pathologist looks at a sample and sees Gleason pattern 3 as the most common pattern and then sees a rare Gleason pattern 4, he would call that tumor a 7 (3+4). If all the pathologist saw was pattern 3, then the cancer would be called 6 (3+3). The Gleason sum ranges from 6 (3+3) to 10 (5+5). Gleason 6 is the least aggressive cancer type, Gleason 7 is intermediately aggressive, and Gleason 8-10 cancer is the most aggressive. In general, cancers with lower Gleason scores are less aggressive while cancers with higher Gleason scores are more aggressive.