Population-based assessment of relationship between volume of practice and outcomes in head and neck cancer patients

• Main Author: McLay, Mary
• Language: English
• Published: University of British Columbia 2017
• Online Access: http://hdl.handle.net/2429/61779

Background and Purpose: Recent literature has suggested that higher volumes of practice are associated with better survival outcomes for head and neck cancer (HNC) patients. However, these studies are limited by looking at the volume of practice on a cancer centre level (i.e. not provider level), and include jurisdictions without central coordination and specialized HNC tumor group support. The objective of this thesis was to evaluate the effect of treatment centre on the overall survival (OS) and cancer-specific survival (CSS) of HNC patients in British Columbia in a provincially coordinated program. Methods: The BC Cancer Registry (BCCR), a population-based provincial database, was used to identify all patients in BC diagnosed for the first time with a primary non-thyroid HNC and treated with radiotherapy between 2006 and 2011. Patients were categorized as residing in large, small and rural local health authorities (LHAs) using BC Stats and BC Ministry of Health information. Physician case frequency was defined as low (0-14 cases per year), medium (15-29 cases per year) and high (>30 cases per year). There was no effect on OS or head and neck CSS when physician case frequency was treated as a continuous variable. Results: 2,330 HNC patients were included in the study. On multivariable analysis, after controlling for age, gender, cancer stage, anatomical site, treatment and physician case frequency, neither head and neck CSS (HNCSS) (HR range=0.86-1.03; p=0.54-0.99) nor OS (HR range=0.91-1.05; p=0.60-0.88) was significantly different by centre. OS was also not significantly different for patients treated by physicians with low case frequency (HR=0.96; 0.81-1.13; p=0.60) and medium case frequency (HR=1.12; 0.84-1.49; p=0.43) in reference to high case frequency. Conclusions: There was no significant difference in survival among BC cancer centres after controlling for differences in rurality, physician case volume and other potential confounding variables. This lack of difference may be in large part due to the centrally coordinated population-run program where radiation oncologists subspecialize, follow provincial guidelines, attend multidisciplinary rounds, have access to radiotherapy quality assurance, and are supported by a HNC tumor group. === Medicine, Faculty of === Graduate