Advanced prostate cancer treatments often used on patients who won’t benefit

Advanced treatment technologies for prostate cancer are increasingly being used on the wrong patients, according to a study published June 26 in JAMA.

Intensity-modulated radiotherapy (IMRT) and robotic prostatectomy use is growing among men with low-risk disease, high risk of noncancer mortality, or both, despite the fact that these patients are unlikely to benefit from such procedures.

“Aggressive direct-to-consumer marketing and incentives associated with fee-for-service payment may promote the use of these advanced treatment technologies,” wrote Bruce L. Jacobs, MD, MPH, University of Michigan, Ann Arbor, and colleagues.

The authors explained that both IMRT and robotic prostatectomy are perceived as being more targeted and less toxic than other therapies. “During a period of increasing population-based rates of prostate cancer treatment, both of these advanced treatment technologies have disseminated rapidly. However, the rapid growth of IMRT and robotic prostatectomy may have occurred among men with a low risk of dying from prostate cancer,” they wrote.

To assess how advanced treatment technologies are being used in comparison with observation, traditional external beam radiation treatment (EBRT) and open radical prostatectomy, Jacobs and colleagues turned to Surveillance, Epidemiology, and End Results (SEER)-Medicare data from 2004 to 2009. They identified a retrospective cohort of prostate cancer patients, of whom 23,633 underwent IMRT, 3,926 underwent EBRT, 5,881 underwent robotic prostatectomy, 6,123 had open radical prostatectomy and 16,384 were more conservatively referred for observation. Follow-up data ran through Dec. 31, 2010.

Clinical stage of T2a or lower, biopsy Gleason score of 6 or less and prostate-specific antigen level of 10 ng/mL or below represented the threshold for low-risk disease. High risk of noncancer mortality was defined as predicted probability of death within 10 years in the absence of a cancer diagnosis.

Results showed that use of advanced treatments increased from 32 percent to 44 percent from 2004 to 2009 among men with low-risk disease, and from 36 percent to 57 percent over that same period among patients with a high risk of noncancer mortality. In those with both low-risk disease and high risk of noncancer mortality, use of advanced treatments rose from 25 percent to 34 percent.

Rates of IMRT and robotic prostatectomy use among all patients diagnosed with prostate cancer increased from 129.2 per 1,000 patients in 2004 to 244.2 per 1,000 patients in 2009, according to Jacobs and colleagues. Over the same period, standard treatments for men least likely to benefit decreased from 11 percent to 3 percent.

“The increasing use of both IMRT and robotic prostatectomy in populations unlikely to benefit from treatment was largely explained by their substitution for the treatments they aim to replace, namely EBRT and open radical prostatectomy,” wrote the authors.

Using advanced treatments in the wrong populations unnecessarily increases costs, as these treatments are more expensive. IMRT is associated with an additional $1.4 billion in total episode payments over alternatives.

“Continued efforts to differentiate indolent from aggressive disease and to improve the prediction of patient life expectancy may help reduce the use of advanced treatment technologies in this patient population,” the authors concluded.