PSA and Prostate Cancer
As a pathologist, I diagnose cancer all too frequently. I have met many patients and families behind the slides and know the devastating impact upon them. Much like the Pap smear and mammogram have transformed cervical and breast cancer detection, the PSA test is doing the same with prostate cancer. PSA is a protein secreted by the prostate and is elevated in many conditions, both benign and cancer. What this means is that it is sensitive for prostate cancer, but not very specific, i.e. there are false positives. This is what makes it a good screening test though. We want to “cast the net wide enough” to catch cancer, but in so doing, we also discover elevations due to benign prostatic hyperplasia (BPH) and inflammation.
Knowing your PSA is the first step. This needs to be combined with age, risk factors, family history, even diet and exercise to determine the next steps. It is a fact that PSA testing has lead to an increase in prostate cancer diagnosis. There are those who question its utility. It is a more complex issue. Your doctor can sort through this and offer you an individualized risk assessment of screening.
My diagnosis gives the team valuable information. Prostate cancer is graded by assigning a Gleason grade (1-5) to the tumor cells and combing the two most prevalent patterns to come up with a score. There exists great inter-observer variability in diagnosis. Multiple experts might interpret a cancer differently, i.e. a diagnosis of 3+3, 3+4, 4+3, 4+4, etc. This can have an enormous impact on care. This is just one grey zone in prostate cancer care.
Treatment too has many grey zones. Should a patient pursue “watchful waiting” or active treatment such as surgery, radiation or even chemotherapy? One exciting advance is a recent study presented by researchers from the National Cancer Institute and reported in the Journal of the American Medical Association. It appears that MRI combined with ultrasound was more accurate in identifying high risk cancers over those of lower risk.
Even with watchful waiting we see a 30-40% upstaging at prostatectomy. Clearly there is more to learn about prostate cancer. What makes cancer cells that look the same under my microscope behave so differently? How can we more accurately sample and stage disease?
The best treatment is that of a multidisciplinary team approach. Combining urology, pathology, oncology, radiology and radiation oncology offers patients an effective plan that is individualized to their disease, another example of “Personalized Medicine”. This information can then be taken back to the patient providing a terrific opportunity for them to learn about their disease, to know what questions to ask, to be advocates for their own care.
As we celebrate Prostate Cancer Awareness this month, let’ take the opportunity to promote a greater awareness of prostate cancer understanding. Let’s get the conversation going. I look forward to the day when the morbidity and mortality of this disease becomes a thing of the past. Much like the recent successes in the battle over breast cancer, the same must occur with prostate cancer. To learn more about the PSA test, check out my recent video