Cancer Sunnybrook Magazine - Spring 2016

Prostate cancer risk calculator to add genetic data

Dr. Robert Nam

Dr. Robert Nam. (Photograph by Doug Nicholson)

Every year, 24,000 Canadian men are diagnosed with prostate cancer. How can we better identify which men are at higher risk for the disease and which men will develop more aggressive forms. How can we be more proactive in our treatment? Is it necessary to treat all forms of prostate cancer? Or is it best to employ an active monitoring strategy? There are no easy answers.

Enter Dr. Robert Nam, head of genitourinary cancer care at the Odette Cancer Centre. Predicting which men are at risk of prostate cancer, and whether that cancer is likely to be slow-growing or aggressive, is the focus of his research.

The tool developed at Sunnybrook to calculate those risks has been shown to be remarkably effective. In fact, the Sunnybrook Prostate Risk Calculator, borne out of basic science and biomarker research, has greater accuracy than a similar tool used widely in the U.S., resulting in Dr. Nam’s team being recognized as a world leader in this area.

Now, the latest research on genetics, biopsy and treatment outcomes is being integrated into the Prostate Risk Calculator: Next Generation. Last year, Prostate Cancer UK awarded Dr. Nam a large grant to research and build on the existing screening tool. He heads an international consortium to develop the new iteration.

A risk calculator uses a statistical model called a nomogram. “This nomogram not only predicts an individual patient’s risk for prostate cancer, but it also gives his risk for the most aggressive forms of the disease,” he explains. “It’s going to say, ‘This patient needs a biopsy,” meaning his calculated risk warrants further tests. Or it tells us that he doesn’t need any intervention at the moment, and careful monitoring through our Active Surveillance with Select Delayed Intervention program would be the best course of action.”

This program aims to reduce overtreatment of clinically insignificant prostate cancer while providing the option of treatment if, over time, the patient becomes higher risk.

Among the data being used in the current version are the patient’s age, digital examination results, family history, ethnicity and PSA-based results. The next-generation version could include results of a test for microRNAs, a new genetic marker for prostate cancer now under investigation by Dr. Nam and Sunnybrook Research Institute colleague Dr. Arun Seth.