One-third of men age 65 and older with abnormal prostate-specific antigen (PSA) levels elect to have a prostate biopsy, yet once cancer is detected most men undergo immediate treatment regardless of advanced age and multiple comorbidities, a study found.
To quantify 5-year outcomes following a PSA screening result exceeding 4.0 ng/mL, researchers conducted a longitudinal cohort study among 295,645 men 65 years or older in the national Veterans Affairs health care system.
Results appeared online April 15 at JAMA Internal Medicine.
In total, 25,208 of the men (8.5%) had an index PSA level higher than 4.0 ng/mL. During the five-year follow-up period, 8,313 of those men (33.0%) underwent at least one prostate biopsy, of which 5,220 (62.8%) were diagnosed with prostate cancer and 4,284 (82.1% of diagnosed cases) were treated for it. While prostate biopsy rates decreased with advancing age and worsening comorbidity (P<0.001), once cancer was found, treatment rates exceeded 75% even among men 85 years or older, those with a Charlson-Deyo Comorbidity Index of 3 or higher, and those having low-risk cancer.
Among men with biopsy-detected cancer, the risk of death from other causes increased with advancing age and worsening comorbidity (P<0.001). There were 468 men (5.6%) who had complications within seven days after prostate biopsy. Complications of prostate cancer treatment included new urinary incontinence in 584 men (13.6%) and new erectile dysfunction in 588 men (13.7%).
Data on outcomes in clinical practice should inform treatment and screening decisions, the authors noted. They wrote, “[D]ecisions to pursue PSA screening should include individualized discussion about when to pursue biopsy and treatment because these steps substantially affect downstream outcomes of screening in clinical practice.”
A research letter in the same issue of JAMA Internal Medicine evaluated whether receiving an inconclusive result from PSA screening, compared with undergoing no test, motivated more individuals to undertake a prostate biopsy.
Researchers recruited 727 men ages 40 to 75 and randomized them to one of four hypothetical situations based on PSA results. In the first situation, “no PSA,” participants were given information about the risks and benefits of prostate biopsies and asked whether they would have a biopsy and the certainty of their decision. In the other three situations, participants were given information about PSA tests, as well as about prostate biopsies, and were then asked to imagine that they'd received normal, elevated or inconclusive results. Participants were then asked about whether they would undergo a biopsy and the certainty of their decision.
Significantly more men said that they would undergo a prostate biopsy if they received an inconclusive PSA test result (40%) than if they had no PSA test (25%; χ2=8.80; P=0.003). Those assigned an elevated PSA test result were more likely to state that they would undergo a biopsy (62%) compared with those who had no PSA test (χ2=47.76; P<0.001) and compared with those assigned an inconclusive PSA test result (χ2=17.89; P<0.001), although 38% of men with an elevated PSA test result still would not opt for a biopsy.
Those assigned a normal PSA test result were less likely to state that they would undergo a biopsy (13%) compared with those who had no PSA test (χ2=8.47; P=0.004), demonstrating some, but not total, reassurance from receiving a normal PSA test result. They were also less likely to state that they would undergo a biopsy than those assigned an inconclusive PSA test result (χ2=35.85; P<0.001) and those assigned an elevated PSA test result (χ2=97.80; P<0.001).
The research letter's authors wrote, “These results suggest that the ubiquitous use of simple but unreliable screening tests may lead to consequences beyond the initial cost and patient anxiety of inconclusive results; they could also lead to investigation momentum.”
On April 9 in Annals of Internal Medicine, ACP issued new recommendations emphasizing that doctors should discuss with men ages 50 to 69 the limited benefits and substantial harms of the PSA before screening for prostate cancer.
There are substantial harms associated with prostate cancer screening and treatment that doctors should convey to patients, ACP said, including the following:
- The PSA test result may be high because of an enlarged prostate but not because of cancer. Or, it may be low even though cancer is present.
- If a prostate biopsy is needed, it is not free from risk. The biopsy involves multiple needles being inserted into the prostate under local anesthesia, and there is a small risk of infection or significant bleeding as well as risk of hospitalization.
- If cancer is diagnosed, it will often be treated with surgery or radiation, which carries risks, including a small risk of death with surgery, loss of sexual function (approximately 37% higher risk), and loss of control of urination (approximately 11% higher risk) compared to no surgery.
ACP recommends against PSA testing in average-risk men younger than 50, in men older than 69, or in men who have a life expectancy of less than 10 to 15 years, because the harms of prostate cancer screening outweigh the benefits for these patients. For men younger than 50, the harms such as erectile dysfunction and urinary incontinence may carry even more weight relative to any potential benefit.
ACP developed this guidance statement for clinicians by assessing current prostate cancer screening guidelines developed by other organizations.