Active surveillance of patients with early-stage prostate cancer “is tackling the problem of overtreatment” and, with rigorous monitoring, “is safe and allows us to treat only patients who need treatment when their cancer progresses,” Ronald C. Chen, MD, MPH, affirmed in an interview with The ASCO Post. That said, a population-based study presented by Dr. Chen at the 2019 ASCO Annual Meeting found that just 15% of patients with low-risk or intermediate-risk prostate cancer were complying with active surveillance monitoring guidelines 18 months after diagnosis.¹ Improving compliance with monitoring guidelines to realize the benefits of active surveillance—as well as to keep it safe—requires “a partnership between the patient and the physician,” Dr. Chen said. “Something more rigorous in terms of monitoring is needed.”

Dr. Chen is Associate Professor, Residency Program Director, and Associate Chair for Education, Department of Radiation Oncology, University of North Carolina at Chapel Hill; and Associate Director of Education, UNC Lineberger Comprehensive Cancer Center, Chapel Hill.

‘Surprisingly’ Low Adherence to Guidelines

Concordance with recommendations by the National Comprehensive Cancer Network® (NCCN®) Clinical Practice Guidelines in Oncology was analyzed for 346 men with low-risk to intermediate-risk prostate cancer enrolled at the time of diagnosis in the prospective, population-based North Carolina Prostate Cancer Comparative Effectiveness and Survivorship Study. The median age of study patients was 66.3 years (range, 42–81 years), and 75% identified as white.

The NCCN recommendations call for prostate-specific antigen (PSA) tests at least every 6 months, digital rectal exams every year, and a repeat biopsy within 18 months of diagnosis.

The biggest difference is that active surveillance has a curative intent, whereas watchful waiting has a palliative intent.

— Ronald C. Chen, MD, MPH

Tweet this quote

“What we thought upfront was that adherence to monitoring would not be perfect,” Dr. Chen was quoted in an online article about the study.² In the interview with The ASCO Post, he added: “When a patient agrees to pursue active surveillance and a physician is on board with that, I would think the physician is laying out a plan for monitoring. When we are not treating the cancer, there is always concern that if we are not monitoring vigorously, the cancer may grow, and we may miss the opportunity for cure. So, I was quite surprised that the figure for following through with the recommended monitoring was only 15%. That is very low.”

Compliance was much higher in the first 6 months, with 67% of patients undergoing a PSA test. “Even in the first 6 months, 67% is not great,” Dr. Chen said. “This still shows that one-third of the patients are not even starting on the right foot. I am not placing blame on the patient. This is really a partnership between the patient and the physician, and again something more rigorous in terms of monitoring is needed.”

Within the first 18 months, 35% of patients had undergone a biopsy, and across all types of recommended tests, just 15% received monitoring compliant with guideline recommendations. Although a decrease in compliance “is commonly what we see in medicine for a variety of reasons,” Dr. Chen noted, and “we did expect it over time, the quick drop down to overall 15% really was quite surprising.”

Difference Between Active Surveillance and Watchful Waiting

Previously published studies of active surveillance have shown prostate cancer–specific mortality rates of 3% at 10 to 15 years of follow-up. “Those studies from academic centers and clinical trials have raised the awareness, one, that we are overtreating cancer, and two, rigorous monitoring—active surveillance—is safe and allows us to treat only patients who need treatment when their cancer progresses,” Dr. Chen said. Because of those well-conducted studies, “the active surveillance uptake in the country has increased quite a bit over the past 10 years, which is great.”

Data derived from trials, however, use rigorous monitoring schedules and “may not represent actual practice,” Dr. Chen cautioned. “The fact that we enrolled a population-based cohort from throughout the state, I think may reflect real practice of what patients are actually going through outside of a clinical trial setting.”

If the 15% monitoring rate is representative of general practice, “that means these patients are not getting active surveillance. They are more likely getting watchful waiting, and that is not the intent of what we are trying to do,” Dr. Chen added. “There is confusion about active surveillance vs watchful waiting. The biggest difference is that active surveillance has a curative intent, whereas watchful waiting has a palliative intent. That is a huge difference that patients should understand.”

Switching to Treatment

Within 2 years, 19% of the study patients had switched from active surveillance to treatment, motivated either by disease progression or anxiety. “There is an opportunity for the physician perhaps to screen early in the active surveillance course” to identify patients not likely to comply with monitoring and “and to act to help them through that,” Dr. Chen noted. For patients identified as being anxious about not receiving immediate treatment, “there could be conversations over time about the safety of active surveillance,” Dr. Chen added.

When patients chose active surveillance, 2 years later most of them felt comfortable with that choice.

— Ronald C. Chen, MD, MPH

Tweet this quote

Patients considered unlikely to follow through with monitoring might benefit from the assistance of a patient navigator—“someone who is charged with ensuring patients come in for follow-up appointments,” Dr. Chen advised. “I know the nurse navigator model has worked quite well with many other cancers, to help coordinate necessary patient care; perhaps another use of that model could be in active surveillance. We can work to create a system to make sure we know who is falling through the cracks and therefore be able to do something about it.”

Few Regrets by Many

At 2 years, 94% of men participating in the study expressed no regret in making a decision to choose active surveillance. “We expected patients to be comfortable with the decision they made,” Dr. Chen said. “The 94%, which is high, was a slight surprise to us. But I think the study findings validate that when patients chose active surveillance, 2 years later most of them felt comfortable with that choice. That was true regardless of whether they stayed on active surveillance or had treatment.”

Increasing Awareness

“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 correctly,” the study authors wrote. “This is a cohort that we continue to follow over time, and we hope we will provide longer term results in a couple of years,” Dr. Chen added.

“We are not trying to reduce active surveillance,” Dr. Chen emphasized. “Active surveillance is tackling the problem of overtreatment, which we recognize. Overtreatment is a problem, and active surveillance tackles that problem. This study unveils that perhaps the pendulum is swinging to another problem, which is actually not monitoring these patients adequately. We hope our study will help us swing back to more rigorous monitoring.” ■

DISCLOSURE: Dr. Chen has served as a consultant or advisor for Accuray, Bayer, Blue Earth Diagnostics, and Medivation/Astellas; and has received research funding from Accuray.

REFERENCES

1. Peterson S, Basak R, Moon DH, et al: Population-based cohort of prostate cancer patients on active surveillance: Guideline adherence, conversion to treatment, and decisional regret. 2019 ASCO Annual Meeting. Abstract 6512. Presented June 2, 2019.

2. Harrison P: Is active surveillance for prostate cancer safe? Medscape, June 5, 2019. Available at https://www.medscape.com/viewarticle/913967. Accessed July 3, 2019.