Implementation of updated Ontario hereditary prostate cancer testing criteria at Princess Margaret Cancer Centre
Emily Thain1, Miran Kenk2, Raymond Kim1,3, Neil E. Fleshner4.
1Familial Cancer Clinic, Princess Margaret Cancer Centre, Toronto, ON, Canada; 2Department of Surgical Oncology, Princess Margaret Cancer Centre, Toronto, ON, Canada; 3Department of Medical Oncology, Princess Margaret Cancer Centre, Toronto, ON, Canada; 4Division of Urology, Princess Margaret Cancer Centre, Toronto, ON, Canada
Introduction: Hereditary cancer genetic testing (HCT) has become a significant component of prostate cancer (PCa) management, and can identify other cancer risks, as well as at-risk relatives.1-5 Despite new Cancer Care Ontario (CCO) guidelines recommending multigene HCT for certain patients with PCa,6 there are limited data on how these patients can optimally access HCT and genetic counselling.7 At the Princess Margaret Cancer Centre (PM), we implemented PCa HCT based on CCO guidelines using two models: HCT initiated by a urologist/oncologist/genetic counsellor in oncology clinic, or by a genetic counsellor in the PM genetics clinic.
Methods: A retrospective review was conducted to assess the implementation of CCO PCa HCT guidelines at the PM. PCa patients who underwent HCT in 2020 and 2021 were reported. A two-tailed t-test was used to compare testing timelines for the two models of care, and a Chi-squared test was used to compare hereditary cancer gene carriers identified through each model of care.
Results: In 2020, of 77 patients were referred; 29 and 48 underwent HCT in oncology and genetics clinics, respectively. In 2021, of 230 patients were referred; 135 and 95 underwent HCT in oncology and genetics clinics, respectively. HCT identified carriers of 10 different hereditary cancer genes (Figure 1). Of patients tested in the genetics clinic, 10.3% were identified as carriers, while 13.5% of patients tested in oncology clinics were identified as carriers (p=0.46). When HCT was initiated in the oncology clinic, results were disclosed to patients an average of 71 days from referral, compared to 129 days for those with HCT through the genetics clinic (p<0.001).
Conclusions: HCT volumes have increased since guidelines became available for Ontario PCa patients. A multidisciplinary approach to HCT was associated with faster time to results. Further study is needed to evaluate the impact of HCT on PCa management and patient perspectives on HCT delivery.
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