Prostate-specific membrane antigen (PSMA) is highly expressed in prostate cancer and a therapeutic target. Lutetium-177 (¹⁷⁷Lu)-PSMA-617 is the first radioligand therapy to be approved in Canada for use in patients with metastatic castration-resistant prostate cancer (mCRPC). As this treatment represents a new therapeutic class, guidance regarding how to integrate it into clinical practice is needed. This article aims to review the evidence from prospective phase 2 and 3 clinical trials and meta-analyses of observational studies on the use of ¹⁷⁷Lu-PSMA-617 in prostate cancer and discuss how Canadian clinicians might best apply these data in practice. The selection of appropriate patients, the practicalities of treatment administration, including necessary facilities for treatment procedures, the assessment of treatment response, and the management of adverse events are considered. Survival benefits were observed in clinical trials of ¹⁷⁷Lu-PSMA-617 in patients with progressive, PSMA-positive mCRPC who were pretreated with androgen receptor pathway inhibitors and taxanes, as well as in taxane-naïve patients. However, the results of ongoing trials are awaited to clarify questions regarding the optimal sequencing of ¹⁷⁷Lu-PSMA-617 with other therapies, as well as the implications of predictive biomarkers, personalized dosimetry, and combinations with other therapies.

Background: Understanding oncology health human resources across Canada is critical to the delivery of quality cancer care. Little has been published about the medical oncology (MO) workforce and trainees; this study sought to characterize trends in the MO workforce and explore the relationship between medical oncologists and cancer incidence as a surrogate demand marker. Materials and Methods: Publicly available databases from the Canadian Medical Association, the Canadian Institute of Health Information, and the Canadian Post MD Education Registry were utilized to estimate the number, demographics, and regional distribution of practicing MOs and MO trainees between 1994 and 2020. Cancer incidence by province was obtained from Statistics Canada. To estimate changes in demand for, and supply of, medical oncology services over time, annual cancer incidence to MO provider ratios were calculated. Results: Between 1994 and 2020, annual cancer incidence nationally rose from 120,255 to 225,800 cases, while the number of MOs increased by 298%. Incident cancer case to medical oncologist (MO) ratio dropped from 749:1 to 352:1 in the same time. However, the MO workforce is aging; in 2020, 40% of providers were ≥50 years old versus 24% in 1994. Trends in Canadian MO trainees mirror MO trends. Ontario has the largest proportion of the country’s MOs (34% in 2020) and MO trainees (49%). Conclusions: Although the Canadian MO workforce has grown, more MO providers are nearing retirement age, which may influence future workforce trends. Ongoing monitoring of human resources in oncology is essential to ensure future demands for services are met.

Introduction: In patients with prostate cancer (PCa), the identification of an alteration in genes associated with homologous recombination repair (HRR) has implications for prognostication, optimization of therapy, and familial risk mitigation. The aim of this study was to assess the genomic testing landscape of PCa in Canada and to recommend an approach to offering germline and tumor testing for HRR-associated genes. Methods: The Canadian Genitourinary Research Consortium (GURC) administered a cross-sectional survey to a largely academic multidisciplinary group of investigators across 22 GURC sites between January and June 2022. Results: Thirty-eight investigators from all 22 sites responded to the survey. Germline genetic testing was initiated by 34%, while 45% required a referral to a genetic specialist. Most investigators (82%) reported that both germline and tumor testing was needed; with 92% currently offering germline and 72% offering tissue testing to patients with advanced PCa. The most cited reasons for not offering testing were an access gap (50%), uncertainties around who to test and which genes to test, (33%) and interpreting results (17%). A majority reported that patients with advanced PCa (74–80%) should be tested, with few investigators testing patients with localized disease except when there is a family history of PCa (45–55%). Conclusions: Canadian physicians with academic subspecialist backgrounds in genitourinary malignancies recognize the benefits of both germline and somatic testing in PCa; however, there are challenges in accessing testing across practices and specialties. An algorithm to reduce uncertainty for providers when ordering genetic testing for patients with PCa is proposed.

1. Prostate cancer is the second most common cancer in men globally, with an estimated 1.5 million new cases in 2022 [1]. In Canada, prostate cancer is the third leading cause of cancer-related dea...

Background: There is a need to identify patients with advanced prostate cancer harboring an inherited mutation in selected DNA damage repair (DDR) genes, as there are prognostic, treatment, and familial risk implications. We aimed to develop a model to predict an individual risk of harbouring a germline DDR gene mutation in patients with metastatic and/or castration resistant prostate cancer (CRPC) disease. Patients and Methods: A retrospective multicenter cohort study was performed on 499 patients with metastatic and/or CRPC, who were tested for germline DDR gene mutations. Clinical and pathologic characteristics were compared between patients with and without a germline DDR mutation. Multivariable logistic regression was employed to develop a prediction model, which was internally validated using a bootstrapping method. Results: Eight predictors (age at diagnosis, time to CRPC, Gleason score, intraductal/cribriform histology, family history, visceral, bone, and lymph node metastases) were included in a logistic model to predict the probability of a germline DDR mutation. A formula to calculate an individual patient’s mutation risk is provided. Two optimal risk cut-offs were explored. Conclusion: We provide a predictive model of germline DDR gene mutation status in patients with metastatic and/or CRPC, using eight clinical-pathologic parameters. Predictive models such as this could be used to estimate a patient’s risk of harbouring a germline DDR mutation to determine prioritization for germline testing.