Is active surveillance for prostate cancer safe?

CHICAGO – According to a population cohort study, only a fraction of men who chose active surveillance (AS) instead of immediate treatment for early-stage prostate cancer are undergoing the recommended monitoring, outside controlled trials.

"What we thought from the outset was that surveillance monitoring would not be perfect, but what we found was that compliance with surveillance was only d & # 39; About 15%. [in our group of men]Ronald Chen, MD, MPH, Associate Professor in the Faculty of Medicine at the University of North Carolina, Chapel Hill, said Medscape Medical News.

This raises the question of whether SA is a good option for patients and if it is safe.
Ronald Chen, MD, MPH

"So, if that's the case, it raises the question of whether SA is a good option for patients and whether it is safe," he added.

The study (Abstract 6512) was presented on June 2 at the annual meeting of the American Society of Clinical Oncology of 2019.

The guidelines established by the National Cancer Network (NCCN) recommend men with low-to-intermediate risk prostate cancer to test their prostate specific antigen (PSA) level at least once every 6 months and undergo an annual digital rectal examination (DRE) and repeated biopsy of the prostate within 18 months of the initial diagnosis.

In this study, a total of 346 men with low-risk or intermediate-risk prostate cancer diagnosed between 2011 and 2013 were followed for 2 years to check their compliance with each of these three components of cancer surveillance of the prostate.

The authors found that the majority of men who chose AS had their PSA tested in the first six months, as well as between 6 and 12 months after their diagnosis – but these numbers dropped with a follow-up long-term.

ERD rates were also relatively high during the two-year follow-up, but biopsy rates were poor at first and continued to decline over time.

Table. NCCN guideline on the prostate cancer cohort during a two-year follow-up

Conversion to active treatment

Chen and his colleagues also discovered that during the first two years after diagnosis, 16% of patients who initially chose AS converted to active treatment – almost half of them chose active treatment in the absence of disease progression, Chen said.

Chen suspects anxiety of being one of the main factors behind the decision to discontinue AS and active treatment – anxiety that he believes could be identified early in AS, and If it is detected, patients advised or referred for additional support to deal with the anxiety related to the disease.

"I want to emphasize that our study is not intended to discourage SA because we recognize that patients with low-risk prostate cancer are over-treated and we can monitor them and avoid treatment in many patients, "Chen said.

"But I think that AS needs more coordination of care to make sure people get the proper follow-up," he said. "If we are going to offer it, we need to make sure that patients are reminded of their appointments, that someone is monitoring the fact that they are getting the supervision they need."

He suggested that the use model of patient browsers, which had been used in other types of cancer, might be needed for men with prostate cancer.

Consequences of non-surveillance

Some clinical studies suggest that AS may not be as effective as immediate treatment if patients are not well monitored.

In the ProtecT trial, for example, there was no difference in mortality specific to prostate cancer between the immediate treatment groups and those badigned to the AS. However, the incidence of disease progression and metastases in the surgery and radiotherapy groups was lower after a median follow-up of 10 years in the immediate treatment group compared to the SA group.

"I think a lot of clinicians reading this essay would say [lack of] careful monitoring leading to lower results in the AS arm, so we can use the ProtecT trial to suspect that, in the real world, AS in men might not do as well as patients who are treated immediately ", observed Chen.

Low compliance rate

Approached by Medscape Medical News Jim Hu, MD, MPH, professor at Ronald P. Lynch urological oncology, Weill Cornell Medicine in New York, said the study did not clearly state whether the patients themselves were less compliant with surveillance guidelines or the fault of providers who did not contact patients to ensure that their follow-up visits were appropriately scheduled to ensure that men undergo additional PSA testing or biopsy.

The study was also conducted at one point (2011 – 2013), where providers were much less comfortable with the idea of ​​AS than today. and could have been more reluctant to offer it.

"What's amazing is that you have such a relatively low compliance rate in early AS wide acceptance, so you might wonder if the compliance rate has changed since there is a greater level of comfort with AS or if it is even lower now that providers are more comfortable with that, "observed Hu.

In contrast, the median age of death for men with prostate cancer in the United States is 80, he said.

Older patients are more likely to die from their disease rather than from it, he added. They may have simply chosen not to worry about PSA screening or biopsy because of their age.

On the other hand, if they were younger men whose cancer was diagnosed at the beginning or in their mid-fifties and they "fell off the wagon", their risk of developing a more aggressive cancer is much greater. long only for older men. placed on AS, as Hu argued.

"It is important to conduct population studies because randomized trials are high-level studies done in an idealistic setting," Hu said.

"And this is an important study because it shows that there is a significant non-compliance with the monitoring and if you do not monitor [men with prostate cancer more closely] so unfortunately, it becomes a blissful ignorance, "he noted.

The study was funded by the Institute for Patient-Centered Outcome Research (PCORI) and the Agency for Health Research and Quality of Health (AHRQ). Chen and Hu did not reveal any relevant financial relationship.

2019 Annual Meeting of the American Society of Clinical Oncology: Abstract 6512. Presented June 2, 2019.

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