September 25, 2020

New risk calculator aids in prostate cancer screening

Created by Kaiser Permanente researchers, the tool is designed to help men and their doctors make informed decisions about the need for biopsy or further testing.

For more than a decade, researchers have debated whether men should have an annual prostate-specific antigen test, or PSA test, to screen for prostate cancer. The controversy centers on the test’s reliability as a tool for predicting whether a man has an aggressive cancer that requires treatment.

“An elevated result doesn’t necessarily mean you have cancer,” explained Joseph Presti, MD, an adjunct researcher at the Kaiser Permanente Northern California Division of Research and the leader of urologic oncology surgery in Northern California. “Even if you do, it might be a low-grade cancer that will never grow any larger.”

But in some cases, an elevated PSA can help identify aggressive cancers before they grow deadly.

A new prostate cancer risk calculator developed by Kaiser Permanente researchers provides information that may help men being screened for prostate cancer make informed decisions about next steps. The calculator predicts a patient’s likelihood of having a biopsy that shows no cancer, a low-grade cancer, or a high-grade cancer following an elevated PSA test or abnormal rectal exam based on factors including age, race, family history of prostate cancer, body mass index, PSA level, and prostate size, among others.

A paper evaluating the accuracy of the risk calculator was recently published in the journal Urologic Oncology. The study found that the calculator provides useful information that may enhance decision-making about the need for biopsy.

“The results can help the patient determine whether to undergo additional tests or have a biopsy,” said Dr. Presti. “Ideally, we would only perform biopsies on men with significant risk of having an aggressive cancer that needs treatment.”

Shared decision-making between men and their doctors

The new calculator is the first to have been developed using a racially diverse population, and the information it provides reflects racial and ethnic disparities in prostate cancer incidence and death. Black men are more likely than men of other races and ethnicities to be diagnosed with prostate cancer and to die from the disease. They are also more likely to develop prostate cancer at a younger age. As a result, the calculator recommends more aggressive screening for Black men than for Asian American, Latino, and non-Hispanic white men.

“By leveraging our large patient database, we sought to create a better tool to help patients and providers determine the value of pursuing a diagnosis after an elevated PSA,” said Andrew L. Avins, MD, MPH, the study’s senior author and a research scientist at the Division of Research.

The calculator is now being tested with another group of 3,000 to 4,000 Kaiser Permanente patients, and findings are expected to be published within the next year. The researchers also hope to assess whether patients and providers find the calculator helpful in their decision-making.

“Based on our initial work, it looks like this tool could help patients make more personally relevant decisions about whether to have a biopsy to look for prostate cancer,” said Dr. Avins. “Our goal is to help them make decisions that are in line with their preferences and values.”