Laurence Klotz, MD, presented “Active Surveillance 2021 – Imaging and Biomarkers” for the Grand Rounds in Urology audience in February 2021.

How to cite: Klotz, Laurence. “Active Surveillance 2021 – Imaging and Biomarkers” February 2021. Accessed Jul 2024.

Active Surveillance 2021 – Imaging and Biomarkers – From Bench to Bedside: Summary

In the second part of a Platinum Lecture trilogy on active surveillance, Laurence Klotz, MD, FRCSC, Professor of Surgery and holder of the Sunnybrook Chair of Prostate Cancer Research at the University of Toronto, outlines recent developments in imaging and biomarkers and discusses how these are changing active surveillance for prostate cancer.

He first reviews the benefits and limitations of MRI targeting, noting that while it has been shown to improve outcomes for men on surveillance, MRI can miss a significant amount of grade group 2 cancer and the negative predictive value of MRI decreases as a patient’s underlying risk increases. Dr. Klotz explains that MRI-targeted biopsy is most useful when combined with systematic biopsy, and that combined biopsies can increase the confidence that one has with monitoring in a way that using MRI alone cannot.

He also looks at the results of studies indicating that targeted biopsy did not increase the rate of finding serious cancer at all and that MRI progression did not correlate with upgrading of men on active surveillance, therefore concluding that while MRI is useful, urologists should not rely on it completely, and other tools are needed to augment it. One such tool is high resolution micro-ultrasound, which has a short learning curve to use and comparable diagnostic accuracy to MRI, and which Dr. Klotz suggests may be a cheaper, simpler alternative to MRI, although more research is needed. Other potentially useful tools include biomarker tests, of which there are many. Dr. Klotz says that these are clearly valuable for the patient about whom there is significant concern about them getting serious cancer, but observes that interfocal heterogeneity challenges the clinical usefulness of molecular classification of primary prostate cancer. He notes, however, that serial biomarkers that provide urologists with a continuous risk index could potentially be of more use for patients on active surveillance. Dr. Klotz concludes by looking to the future, suggesting that data integration and artificial intelligence in active surveillance will be available very soon.        

For more on active surveillance for prostate cancer, check out our collection page for the 2020 International Prostate Cancer Update!


Laurence Klotz, MD, FRCSC, is a professor of surgery at the University of Toronto and the Sunnybrook Chair of Prostate Cancer Research. Dr. Klotz was the founding editor-in-chief of both the Canadian Journal of Urology and the Canadian Urology Association Journal (CUAJ), and he is now editor emeritus of the CUAJ. Dr. Klotz obtained his medical degree and completed his residency at the University of Toronto. He was also a uro-oncology fellow at Memorial Sloan Kettering Cancer Center in New York.

Dr. Klotz has 550 peer review publications and eight books. He coined the phrase “active surveillance” and successfully championed this approach for men with favorable-risk prostate cancer against substantial resistance. He was the associate editor of the Journal of Urology, responsible for prostate cancer, for eight years. Dr. Klotz received the Queen’s Jubilee Medal for outstanding public service, the University of Toronto's Lister Prize, the Society of Urologic Oncology’s SUO Medal, the American Urological Association’s Richard Williams Award, the University of Toronto's Lifetime Achievement Award, the Canadian Urological Association Lifetime Achievement Award, and the Harold Warwick Award from the Canadian Cancer Society for “outstanding contributions to cancer control.” In 2015 he was inducted as a Member of the Order of Canada, Canada’s highest civilian award.