Prostate Cancer Archive

Low levels of vitamin D may help predict aggressive prostate cancer, according to new research. While it only showed an association, the researchers believe low D levels could be used as a valuable biomarker, and help men and their doctors decide whether to consider active surveillance, in which the cancer is monitored for changes.  

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A research letter published online Jan. 21, 2016, in JAMA Oncology suggests that many older adults are getting unnecessary cancer screenings. Researchers looked at questionnaire answers from about 150,000 seniors (ages 65 or older) across the country, and found that about half had received prostate-specific antigen (PSA) testing or mammography in the past year. But a third of those screened did not have a 10-year life expectancy, a major guideline for screening. Unnecessary screening rates varied by state—for example, 11% in Colorado and about 20% in Georgia. "Undergoing a screening test may actually cause more harm than good, especially with older patients or those with significant medical conditions," says Dr. Marc Garnick, an oncologist at Beth Israel Deaconess Medical Center and editor in chief of Harvard's Annual Report on Prostate Diseases. So talk to your doctor about the guidelines. Both the American Cancer Society (ACS) and the U.S. Preventive Services Task Force (USPSTF) recommend routine mammograms every two years for women ages 55 to 74. The ACS does not recommend mammograms in this age group if a woman has a life expectancy of less than 10 years.

For all men, the USPSTF recommends against routine PSA testing. The ACS suggests that men 50 or older (at average risk for prostate cancer) make the decision about screening with their doctor, but only if they have a life expectancy of at least 10 years, and only if they have been advised about the uncertainties, risks, and potential benefits of prostate cancer screening.

A study in the December 2015 issue of The Lancet Oncology found that a new test, called STHLM3, is more helpful at detecting aggressive cancer than traditional tests for prostate-specific antigen (PSA).

The STHLM3 test is a blood test that analyzes a combination of six protein markers, more than 200 genetic markers, and various clinical data, such as age, family history, and previous prostate biopsies.

Ask the doctor

Q: I am 68 years old, and recently my PSA level (which was normal before) increased to 5.2 nanograms per milliliter (ng/ml). My doctor repeated the test one month later, and it was normal again at 3.3 ng/ml. Should I still be concerned?

A: One of the reasons that routine PSA testing is so controversial is the inability of the test to distinguish men with prostate cancer from those without it. A common cutoff is 4 ng/ml, but this is hardly a black-and-white answer. In fact, 30% of men with a PSA result between 4 and 10 have cancer. (The remaining 70% have benign causes, like an enlarged prostate.) In men with a "normal" PSA in the 2-to-4 range, 20% have cancer. So the risk is still present.

In the journals

If you have suffered a heart attack and plan to undergo prostate cancer treatment, you may want to weigh the risks and benefits of androgen deprivation therapy (ADT). ADT decreases the amount of androgens in the body, which prostate cancer needs to grow and survive. It is also often used along with radiation therapy, and the combination has been shown to prolong survival in men with unfavorable-risk prostate cancer—defined as cancer with two or more high-risk factors, like a PSA level between 10 and 40 ng/mL, a Gleason score of 7 or higher, or biopsies with 50% or higher cancerous cells.

But a study in The Journal of the American Medical Association suggests that men who had a prior heart attack can increase their risk of a fatal one if they undergo both radiation therapy and ADT. Researchers compared overall survival and death from prostate cancer, fatal heart attack, and other causes in a group of 206 men with unfavorable-risk prostate cancer. The men received either radiation alone, or radiation and six months of ADT. The researchers also categorized the men into subgroups based on other health conditions, including heart disease.

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Ask the Doctor

Q. I had a vasectomy many years ago, at age 45. I recently read that this increases my risk of prostate cancer. Should I be concerned?

A. Despite the reports you've heard about the connection between vasectomy and prostate cancer, the evidence is weak for a cause-and-effect relationship. Right now, this hypothetical risk should not cause you undue concern.

Q. Some of my friends take saw palmetto supplements to reduce urinary problems caused by an overgrown prostate, which I was recently diagnosed with. My friends swear by it, but is there any good evidence this stuff helps? Is saw palmetto safe?

A. The short answer is that we don't have great scientific evidence that taking saw palmetto truly reduces male urinary problems. On the other hand, it doesn't appear to cause major side effects either.

An approach called active surveillance allows some men with low-risk cancer to delay the decision to treat.

Biomarkers are "chemicals" that can indicate both normal and abnormal processes in the body. One of the most famous is prostate-specific antigen (PSA). The PSA test, which detects abnormally high blood levels of PSA, has been used for decades to screen for prostate cancer and potentially catch it early.

There are two problems with the PSA test. First, PSA levels can tell you that something is going on with the prostate — but that "something" isn't necessarily cancer. High levels may mean other benign prostate conditions. Second, when high PSA levels do turn out to be the result of prostate cancer, the PSA level alone won't tell you which cancers are aggressive and need treatment, and which are slow-growing and can be managed more conservatively.

Q. I am scheduled to have my prostate removed and am concerned about the risk of erectile dysfunction (ED) after the surgery. I've heard that taking an ED drug daily during my recovery could help. Do you recommend this?

A. About half of men lose some erectile function after radical prostatectomy, which removes the entire prostate gland. ED drugs help men to have erections after surgery, but so far research has not shown that taking it daily produces better results than taking the medication as-needed—when you anticipate sexual activity.