Active surveillance reduces unnecessary treatment in prostate cancer

Toronto – The use of active surveillance (AS) has increased substantially and is proving to have advantages over the older approach of more treatment up front. The approach of active surveillance (AS) is actually a Canadian concept, and since the 1990s has become the standard of care for low-risk prostate cancer management worldwide, said Dr. Antonio (Tony) Finelli head of the division of urology at the Princess Margaret Cancer Centre and a professor of surgery at the University of Toronto. In part, it was developed as an answer to overly aggressive treatment in low-risk cases that sometimes happened as a result of PSA screening. AS was intended to help mitigate that. Previously, many men underwent prostatectomy and radiation early-on which may not have been needed until later years, he said. “We know both of those treatments affect urinary control and sexual function. There was significant quality of life issues associated with intervention,” he told The Medical Post in an interview. If that could be delayed or avoided, then everyone benefits. Read: Sexual side effects But there have been questions of how long patients benefit from AS before they need further treatment and the patterns of its use. To help answer these questions, Dr. Finelli and colleagues conducted a study describing the uptake, discontinuation and variation of AS use by provider and patient level characteristics. Findings were published in The Journal of Urology. The observational, population-based study used linked administrative databases at the Institute for Clinical Evaluative Sciences (ICES) and included men who were diagnosed with prostate cancer between January 1, 2008 and December 31, 2014 throughout Ontario. The data extracted were for men who were newly diagnosed with Gleason Grade Group 1 (GG1) prostate cancer in that time frame. Researchers identified all men who had a confirmatory biopsy (second biopsy of more than 60 days from the diagnostic biopsy) within two years after the diagnostic biopsy. Patients were followed from the date of diagnosis until the start of definitive treatment, loss to followup, death, metastatic progression, or a data lock period (which was Dec. 31, 2017) –whichever came first. The final study cohort consisted of 16,852 patients. A total of 8,541 (51%) were managed by AS, 6,042 (36%) received treatment at diagnosis, and 2,268 (13%) underwent Watchful Waiting (WW). In this context, the WW study differed from AS in that there were no confirmatory biopsies. Protocols for AS appear in various guidelines for prostate cancer. While there are minor variations to the approach, the key steps are: once the patient is diagnosed and confirmed as having low-risk prostate cancer and agrees with the approach a PSA test is done every three to four months in the first year, and then a repeat biopsy usually a year after the diagnosis. Some places will also conduct MRI studies. The timing of biopsies varies between centers. “Some places will do it at six months, some will do it up to 18 months. But usually within a year you have a repeat biopsy,” Dr. Finelli said. Increased popularity of AS The study found that AS became more commonly used, and increased substantially from 38% in 2008 to 69% in 2014. Likely this means both physicians and patients have a greater comfort with the concept, he said. “You preserve quality of life, and if all goes according to plan you don’t miss the opportunity to use cure if it is needed. If the disease becomes higher grade on follow-up biopsy, we intervene,” he said. It was also found that at a median of 48 months, 51% patients had discontinued AS. The cumulative probability of remaining on AS and being treatment-free at 1, 2, 3, 4 and 5 years was 85.2%, 62.9%, 58.0%, 55.3% and 52.4% respectively, the study said. Discontinuation of AS was defined as the receipt of any definitive intervention (surgery or radiation) or treatment with primary androgen deprivation therapy (ADT). There was pathological progression in 3,007 of the patients. Of those who progressed 86.5% received definitive treatment, while 483 (8.7%) patients were treated who had no pathological progression. The majority of patients (52%) who discontinued AS had an increase in their Gleason score of GG2 or higher. There were several factors associated with transition to definitive treatment. These were younger age, higher number of comorbidities, and worse disease characteristics (higher PSA levels, increased number of positive cores, greater cancer volume). There were also provider factors affecting when AS was discontinued. Transition to treatment was more common at higher volume clinics, academic centres and if patients were treated by a radiation oncologist verses a urologist. Generally, the study found men at low-risk are getting appropriate care with no increased risk when to comes to their cancer. Communicating what patients should expect from AS is vital, Dr. Finelli said. “Patients need to have realistic expectations so they are not disappointed five or six years later if they require intervention. And that they have a choice,” he said. There are a number take homes from this study, according to Dr. Stuart Edmonds, executive vice-president, mission, research and advocacy at the Canadian Cancer Society. A key one is the increased use of AS. “That tells me is that we’re managing these guys with lower risk in a much more responsible way. We’re not rushing guys to get treatment if it’s not necessary,” he said. “The other piece that came out of this is, if indeed the cancer does progress then, through a shared decision-making process, treatment is available. The fact that around 50% went on to treatment over that period of time shows that we are appropriately managing these men who have low risk disease,” Dr. Edmonds said.

Active surveillance reduces unnecessary treatment in prostate cancer

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