Outcomes of active surveillance for prostate cancer may vary with age

The benefits of active surveillance for prostate cancer appear to be greater in men diagnosed with low-risk prostate cancer at an older age, according to a study from Sweden.

“Men diagnosed [before age] 60 [years and managed with] active surveillance have a greater likelihood of dying of prostate cancer with very little added benefit, in terms of extra years with no other treatment,” pointed out study author Dr Eugenio Ventimiglia, a urologist at San Raffaele Hospital, Milan, Italy, and PhD student at Uppsala University, Uppsala, Sweden, at EAU21.

Conversely, the benefits of active surveillance were greater for men diagnosed after age 65 years, particularly those with low-risk prostate cancer, said the authors.

Using the nationwide, population-based Prostate Cancer data Base Sweden (PCBaSe), the authors identified 23,649 men diagnosed with prostate cancer who were managed with active surveillance or watchful waiting. State-transition estimates of deaths from prostate cancer or other causes, and proportion of time without active treatment for prostate cancer were examined from date of diagnosis until death or age 85 years (30-year estimate of active surveillance outcomes).

The risk of death from prostate cancer before age 85 years was higher among men diagnosed at a younger vs older age (55 vs 70 years). Specifically, among men diagnosed at age 55 years, death rates were 10, 13, and 15 percent among those categorized as very low risk, low risk, and intermediate risk, respectively. In contrast, the rates were 4, 6, and 7 percent, respectively, among men diagnosed with prostate cancer at age 70 years. [EAU21, abstract P1048]

Among men diagnosed with prostate cancer at age 55 years, men with very low, low, and intermediate risk spent a mean 11, 9, and 7 out of 25 years without active treatment, equivalent to 45, 37, and 29 percent of time, respectively. Men diagnosed with prostate cancer at age 70 years with very low, low, and intermediate risk spent a mean 10, 9, and 8 out of 13 years, respectively, without active treatment, equivalent to 75, 67, and 60 percent of time, respectively.

“Due to the relatively recent introduction of active surveillance for prostate cancer, there is a general lack of appraisal regarding [its] long-term safety … for different patient groups,” said Ventimiglia.

“We wanted to identify the real winners from active surveillance, the men who are unlikely to die from their prostate cancer but who will also spend most of their remaining years without treatment if the disease is carefully monitored,” he continued.

“[This study showed that] men with intermediate-risk prostate cancer diagnosed [before age] 60 years had little benefit in terms of time without active prostate cancer treatment (29–33 percent) considering their high risk of prostate cancer death (12–15 percent),” said the authors.

“[M]en older than 65 years with low-risk prostate cancer had a larger benefit in terms of both longer time without active prostate cancer treatment (60–75 percent) and lower risk of prostate cancer death (4–6 percent),” they added.

“Obviously, the older you are and the lower risk your cancer, the greater the benefit. But we saw a real divide at age 60,” noted Ventimiglia. “After 60, if your cancer is low-risk, then active surveillance is really a win-win,” he concluded.