‘Watch-and-wait’ approach for low-risk prostate cancer not without dangers

Leanne Burnham holding up test tube
Leanne Burnham, Ph.D.
According to a recent study published in the Journal of American Medicine, men diagnosed with “low-risk” prostate cancer are increasingly refusing more aggressive treatment in favor of a watch-and-wait approach.
In 2010, just 14.5 percent of men diagnosed with low-risk prostate cancer chose “active surveillance” as a means of monitoring the progression of the disease; in 2014, that number rose to 42.1 percent.
Prostate cancer is the second most common type of cancer among men, with over 1.3 million new diagnoses in 2018. According to the National Cancer Institute, about 11.2 percent of men will be diagnosed with prostate cancer at some point in their lives.
Because lower-risk prostate cancer tends to develop and grow more slowly than other cancer types, and because radiotherapy or surgical options are often accompanied by side effects that can negatively impact a patient’s quality of life (including erectile problems and incontinence), more and more patients are considering less-aggressive alternatives.
The new study focused on data from 164,760 men diagnosed with prostate cancer in the United States between 2010 and 2015, including information on each patient’s approach to treatment. Researchers found that among men with a “low-risk” diagnosis, the use of active surveillance increased, while radical prostatectomies and radiotherapy fell.

Not 'One Size Fits All'

According to Leanne Burnham, Ph.D., postdoctoral fellow in the lab of Rick Kittles, Ph.D., founding director of the Division of Health Equities within City of Hope's Department of Population Sciences, this changing trend toward less radical treatment can be viewed as a positive development for low-risk cancer patients, with some important caveats. “Overall, the potential outcome for this trend is positive,” explained Burnham.
But you have to remember that what we consider a ‘low-risk’ classification is not ‘one size fits all’ for all patients.”
Determining which patients truly fall into the “low-risk” category can prove more complicated than some tests would make it seem. “For example,” Burnham explained, “some studies show that African-American men are initially categorized as low-risk patients following a biopsy. When these patients have their prostates removed, we’re learning that many had more aggressive features of prostate cancer than the biopsy had indicated.”
A biopsy may indicate that a patient has a less aggressive prostate cancer, and it’s only after surgery that their cancer classification is upgraded. Because cancer “cores” can be located in different zones of the prostate in different races of men, and those may not be sampled in a less sophisticated biopsy, Burnham cautions against making low-risk designations that don’t take these factors into account. “There’s the potential for some men to go in for a biopsy, not have these particular zones biopsied, and be classified as low risk, when in reality, the region of their prostate where cancer was present was never accessed,” she explained.
These patients may have much more aggressive features of cancer than diagnosed, and may run the risk of not learning about the progression of the disease until the disease has spread. “If you wait too long,” explained Burnham, “once the cancer spreads outside of the prostate, there are plenty of treatment options available, but we have yet to find a silver bullet cure.”
More modern techniques in imaging, including MRI-guided biopsies, may provide a more thorough and accurate diagnosis, but many men are less likely to have the procedure done due to cost.
In addition, for all men who choose active surveillance, strict adherance to followup screenings is key. "Some cancers will be more aggressive than predicted by the initial diagnosis features, and those men will end up needing radical/definitive therapy with surgery or radiation," said Tanya Dorff, M.D., associate clinical professor in the Department of Medical Oncology & Therapeutics Research at City of Hope. "What we aim to do is find those cancers that will not threaten a man's life and spare those men from the potential side effects of definitive treatment. But one of the most important aspects of active surveillance is adherance to the followup protocol, including biopsies. If we don't watch the cancer, there is the risk of missing a window of curability." Men who choose active surveillance must be committed to the routine followup and repeat biopsy schedules, she said.

Surveillance or Treatment?

The limitations of the brief study were also an area of concern for Burnham. “The study looked at patient decisions over only a five-year period. It’s not yet known how these trends will translate into clinical outcomes.”
“Overall, I’d like to say that this trend is a good thing. However, previous studies that have focused more on African-American men have suggested that they may not fare as well,” Burnham said. “We need to be very careful about who we are designating as low-risk patients.”
The decision to choose active surveillance over more aggressive treatment options continues to be a very personal one. “Some patients may feel empowered by choosing active surveillance, and we can’t underestimate how those feelings impact their quality of life,” said Burnham. “We just want to make sure that patients have a clear understanding of all of the options, and all of the risks, before they make an important life-altering decision.”