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The purpose of this document is to provide pre-analytical, analytical and post-analytical considerations and recommendations to Canadian clinical laboratories developing, validating and offering next-generation sequencing (NGS)-based BRCA1 and BRCA2 (BRCA1/2) tumour testing in ovarian cancers. This document was drafted by the members of the Canadian College of Medical Geneticists (CCMG) somatic BRCA Ad Hoc Working Group, and representatives from the Canadian Association of Pathologists. The document was circulated to the CCMG members for comment. Following incorporation of feedback, this document has been approved by the CCMG board of directors. The CCMG is a Canadian organisation responsible for certifying medical geneticists and clinical laboratory geneticists, and for establishing professional and ethical standards for clinical genetics services in Canada. The current CCMG Practice Guidelines were developed as a resource for clinical laboratories in Canada; however, they are not inclusive of all information laboratories should consider in the validation and use of NGS for BRCA1/2 tumour testing in ovarian cancers.

Objectives In precision medicine, where oncologic management is tailored to the individual’s clinical and genetic profiles, advanced diagnostic testing provides prognostic information and guides management in a growing number of malignancies. There is a need to capture the work pathologists perform to meet this demand by providing medically relevant, timely, and accurate testing results. This work includes not only direct patient consults (interpretation of results and issuing reports) but the administrative and medical oversight as well as the research needed to provide the necessary quality assurance, quality control, direction, and framework for the laboratory. Methods An expert panel of Canadian pathologists involved in advanced diagnostics was convened to establish and beta test a model for workload assessment in advanced diagnostics. Results All aspects of the advanced diagnostics workload were detailed and applied to models based on members’ experience, including medical oversight, administration, and the introduction of new testing and platforms. Models for biomarker testing were developed for simple and complex or multiplexed assays, and a detailed model was developed to assess the workload for next-generation sequencing–based assays. Conclusions This paper provides the first detailed proposal for capturing an advanced diagnostic workload to enable appropriate pathologist allotment for performing all the steps required to run an advanced diagnostic service.

PurposeHuman papillomavirus-associated (HPV+) head and neck squamous cell carcinoma (HNSCC) is the fastest rising cancer in North America. There is significant interest in treatment de-escalation for these patients given the generally favourable prognosis. However, 15-30% of patients recur after primary treatment, reflecting a need for improved risk-stratification tools. We sought to develop a molecular test to predict the survival of patients with newly diagnosed HPV+ HNSCC.MethodsWe created a prognostic score (UWO3) that was successfully validated in six independent cohorts comprising 906 patients, including blinded retrospective and prospective external validations. Transcriptomic data from two aggressive radiation de-escalation cohorts were used to assess the ability of UWO3 to identify patients who recur. Multivariate Cox models were used to assess the associations between the UWO3 immune class and outcomes.ResultsA three-gene immune score classified patients into three immune classes (immune rich, mixed, or immune desert) and was strongly associated with disease-free survival in six datasets, including large retrospective and prospective datasets. Pooled analysis demonstrated that the immune rich group had superior disease-free survival at 5 years to the immune desert (HR= 9.0, 95% CI 3.2–25.5, P=3.6×10−5) and mixed (HR=6.4, 95%CI 2.2–18.7, P=0.006) groups after adjusting for age, sex, smoking status, and AJCC8 clinical stage. Finally, UWO3 was able to identify patients from two treatment de-escalation cohorts who remain disease-free after aggressive de-escalation to 30 Gy radiation.ConclusionsThe UWO3 immune score could enable biomarker-driven clinical decision-making for patients with HPV+ HNSCC based on robust outcome prediction across six independent cohorts. The superior survival of immune rich patients supports de-intensification strategies, while the inferior outcomes of the immune desert patients suggest the potential for intensification and/or immunotherapy. Prospective de-escalation and intensification clinical trials are currently being planned.