Most prostate cancer patients who choose to undergo active surveillance instead of treatment are not receiving the appropriate disease monitoring, bringing into question whether or not this is a safe treatment option, according to a population-based study.
The study, “Population-based cohort of prostate cancer patients on active surveillance (AS): guideline adherence, conversion to treatment and decisional regret,” was presented at the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.
The approach consists of actively monitoring the cancer to detect disease progression before starting any treatment, and “has rigorous guidelines,” Ronald C. Chen, MD, associate professor at the UNC School of Medicine, said in a press release. “People need regular PSA [prostate-specific antigen] tests, they need prostate exams, they need prostate biopsies so you can watch the cancer very closely, and you don’t lose the opportunity to treat the cancer when it starts to grow.”
Data from large academic institutions and clinical trials have shown that active surveillance is safe and results in low rates of cancer-specific mortality. However, the approach has not been previously examined in a real-life setting.
In collaboration with the North Carolina state cancer registry, researchers enrolled 346 men with newly diagnosed prostate cancer with low or intermediate risk who chose active surveillance rather than treatment.
Medical records and patient-reported outcomes were evaluated using validated measures of prostate cancer anxiety known as MAX-PC and Clark’s prostate cancer decision regret.
Monitoring during active surveillance was assessed using current National Comprehensive Cancer Network (NCCN) guidelines. These included PSA testing every three to six months, digital rectal exams every year, and prostate biopsy within 18 months of diagnosis.
Results indicated that only two-thirds of patients received a PSA test and 70% underwent a digital rectal exam in the first six months. Just 35% received an appropriate prostate biopsy within 18 months.
Overall, only 15% of patients received guideline-adherent monitoring in the first two years.
“Based off of the NCCN guidelines, which is what we believe most of the community practices would be following in terms of active surveillance guidelines, we’re finding very few patients who elected to undergo active surveillance actually received the recommended monitoring,” said Sabrina Peterson, first author of the study.
“This raises the question of whether we need to investigate whether active surveillance is a safe option when patients do not receive routine monitoring,” Chen said. “Our goal is not to reduce the number of patients choosing active surveillance; rather, the results of this study should increase awareness and efforts to ensure that active surveillance patients are monitored rigorously.”
Researchers also found that 16% of patients went from active surveillance to treatment within the first two years. While disease progression was a major reason for switching to treatment, anxiety was also making patients move to treatment.
No other sociodemographic factors — including education, race, marital status, or rural/urban location — or diagnostic variables were associated with conversion to treatment. At two years, only 6% of patients said they regretted going through active surveillance.
“While there are continued efforts to increase AS [active surveillance] uptake, these results highlight the importance of behavioral interventions during active surveillance to reduce anxiety and improve monitoring adherence. Whether AS in non-controlled settings is safe and effective requires further study,” the researchers wrote.