Current PSA Monitoring Ignores Risk to Some Prostate Cancer Survivors

Prostate cancer survivors make up the largest group, 41 percent, of male cancer survivors. In these survivors, early detection of recurrence can lead to life-saving interventions, but in older men who survived low-risk cancer and have limited life expectancy, those same interventions may do more harm than good.

However, when UC San Francisco researchers analyzed current monitoring practices, they found that doctors use a one-size-fits-all approach to monitoring – performing the same frequency of testing regardless of a survivor’s health and prognosis. In a new study, the researchers recommend that doctors individually tailor how often older prostate cancer survivors who have undergone curative treatment are monitored for disease recurrence.

The study is online Feb. 8, 2018, in the Journal of General Internal Medicine.

This is the first study suggesting a need for guidelines to encourage prostate-specific antigen (PSA) monitoring that considers life expectancy, risk of recurrence, and the values and preferences of cancer survivors rather than a one-size-fits-all approach, said senior author Louise Walter, MD, chief of the UCSF Division of Geriatrics and geriatrician at the affiliated San Francisco VA Health Care System.

After surgery or radiation, some data suggest the interventions given just after early detection of recurrence based on elevated PSA levels may improve survival. But PSA monitoring may lead to complications from invasive diagnostics or treatment and may even be unnecessary in older men with a history of low-risk cancer or limited life expectancy.

In the study, Walter and her colleagues examined the national VA and Medicare data of 13,397 men age 65 or older diagnosed with prostate cancer between Jan. 1, 2003, and Dec. 31, 2008, and treated with radiation or radical prostatectomy. All participants were followed for four years after their one-year treatment anniversary date.

Men with limited life expectancy treated for low-risk cancer are least likely to experience disease recurrence in their lifetime, making them the most likely to experience harms of PSA monitoring without benefit. However, these men received only marginally fewer PSA tests per year compared to men with longer life expectancy treated for high-risk cancer, the group most likely to benefit from monitoring.

The researchers note that the most consistent predictor of monitoring frequency was time since treatment, slightly decreasing every year, rather than any patient characteristic. The narrow range of PSA monitoring frequencies across patient and tumor characteristics indicates little individualization in how clinicians currently monitor for prostate cancer recurrence in older men, Walter said.

Most of the men received approximately two PSA test per year, which is consistent with current guidelines. The researchers hope their study will encourage new guidelines that take a more patient-focused approach to monitoring.