Prostate Cancer is the most common cancer among men in the United States, and the second leading cause of fatal cancers. It’s much more common in men >65 years-old. Strategies for diagnosis have been controversial. Here’s an explanation.
On autopsy studies of elderly men who died of unrelated conditions like heart attacks, strokes, accidents, infections, etc., approximately 90% of 90-year-old men had prostate cancer. But it didn’t kill them. So if we find prostate cancer in a younger man, it can be hard to know for sure whether that cancer will be fatal, or just remain irrelevant for many years.
Symptoms of early prostate cancer are the same as the much more common Benign Prostatic Hypertrophy (now called “LUTS”). Most of the time, cancer is first suspected by finding an elevated Prostate Specific Antigen (PSA) on a screening blood test. “Elevated” usually means over 4.0 ng/mL (higher cut-offs for older men). If a man is taking the prostate medications finasteride or dutasteride, he should double his result. Some clinicians like to also measure the amount of “free PSA;” the higher the proportion of free PSA, the more chance there’s cancer. Also, rapid rises in PSA over time are more suspicious for cancer.
The next step after an abnormal PSA is to obtain a biopsy. A transrectal ultrasound (performed by a Urologist, through the rectum) might find a suspicious area. But regardless, about 12 biopsy specimens will be taken, from different areas. There is a small risk of serious infection from the biopsy procedure. A biopsy might be avoided by obtaining a prostate MRI; if this is normal, the chance of prostate cancer may be low despite the PSA.
If the biopsy shows cancer, it will be graded by the Gleason scale, scored from 6 to 12. Gleason scores of 6 (maybe 7) are considered early prostate cancer. Anything higher is more advanced, and should be treated in one way or another. Most biopsies tend to wind up Gleason 6 or 7.
With a low Gleason score, the Urologist will probably also order genetic testing on the cancer tissue, and perhaps also an MRI. The latter two tests can help decide if the cancer truly seems to be early.
If indeed the cancer seems to be early, patients are offered possible strategies:
- “Active Surveillance” — no treatment, but frequent testing to see if anything changes. Advantage: no risky treatment. Disadvantage: some people have lots of Anxiety.
- Radiation Treatment — Advantage: good success at controlling the cancer. Disadvantage: risks of radiation injury, when maybe the cancer would never have advanced.
- Radical Prostatectomy (major surgery to remove the prostate) – Advantage: cancer will likely be cured. Disadvantage: 40-50% of men have significant impotence or incontinence afterwards, especially men older than 60-70. And we still never know if the early cancer would have ever become fatal.
If the above strategies don’t seem appealing, patients should consider not obtaining a PSA in the first place. There’s no good proof that doing the blood test helps people live longer. Some formal recommendations include:
- United States Preventive Service Task Force (USPSTF: an independent body created by Congress) is neutral for men <70, says “don’t” for men >70.
- American Cancer Society simply says to discuss it with your primary provider
- American Urological Association recommends screening for men <70 with a 10-15 year life expectancy.
Before I even order the PSA, I explain this, & suggest to patients, “There are 2 types of people. One definitely cannot bear the thought of having cancer, wants to know, and if found, wants it removed; they should get a PSA. The other doesn’t want procedures that may be risky, without knowing for sure it will help them live linger; these men shouldn’t even get the blood test.”