Investigating epidemiologic trends and the geographic distribution of patients with anal squamous cell carcinoma throughout Canada.

Background: Anal cancer is a rare disease, constituting 0.5% of new cancer cases in the United States. The most common subtype is squamous cell carcinoma (scc). Studies in several developed nations have reported on an increasing incidence of anal cancer in recent decades, and various risk factors pertaining to the pathogenesis of the disease have been identified, including infection with the human papillomavirus, tobacco use, and immunosuppression. The epidemiology and distribution of anal scc throughout Canada remain poorly understood, however. Methods: Using 3 population-based cancer registries, a retrospective analysis of demographic data across Canada for 1992-2010 was performed. The incidence and mortality for anal scc was examined at the levels of provinces, cities, and the forward sortation area (FSA) component (first 3 characters) of postal codes. Results: During 1992-2010, 3720 individuals were diagnosed with anal scc in Canada; 64% were women. The overall national incidence rate was 6.3 cases per million population per year, with an average age at diagnosis of 60.4 years. The incidence increased over time, with significantly higher incidence rates documented in British Columbia and Nova Scotia (9.3 cases per million population each). Closer examination revealed clustering of cases in various urban centres and self-identified lgbtq communities in Toronto, Montreal, and Vancouver. Discussion: This study provides, for the first time, a comprehensive analysis of the burden of anal scc in Canada, identifying susceptible populations and shedding light onto novel avenues of research to lower the incidence of anal cancer throughout the country.

Epidemiology of adult and pediatric Burkitt lymphoma in Canada: sequelae of the HIV epidemic.

Background: Although the pathogenesis and epidemiology of endemic Burkitt lymphoma (bl) have been extensively studied, the epidemiologic landscape of sporadic and immunodeficiency-associated bl in North America remains poorly understood. Methods: We used 3 distinct population-based cancer registries to retrospectively study bl incidence and mortality in Canada. Data for patient sex; age at the time of diagnosis; and reporting province, city, and forward sortation area (fsa, the first three characters of a postal code) were analyzed. Results: During 1992-2010, 1420 patients with bl in Canada were identified (incidence rate: 2.40 cases per million patient-years), of which 71.1% were male patients. Mean age at diagnosis was 55.5 ± 20.8 years. A bimodal incidence by age distribution was seen in both sexes, with pediatric- and adult-onset peaks. An analysis based on fsas identified select communities with statistically higher rates of adult bl. Several of those fsas were located within the 3 major metropolitan areas (Montreal, Vancouver, Toronto) and within self-identified lgbtq communities. The fsas with a higher socioeconomic status score were associated with lower rates of bl. Conclusions: Current results highlight the geographic and historic pattern of bl in Canada. The human immunodeficiency virus remains an important risk factor for adult bl.

Incidence and mortality trends and geographic patterns of follicular lymphoma in Canada.

Background: Follicular lymphoma (fl) is the most common indolent lymphoma and the 2nd most common non-Hodgkin lymphoma, accounting for 10%-20% of all lymphomas in the Western world. Epidemiologic and geographic trends of fl in Canada have not been investigated. Our study's objective was to analyze incidence and mortality rates and the geographic distribution of fl patients in Canada for 1992-2010. Methods: Demographic and geographic patient data for fl cases were obtained using the Canadian Cancer Registry, the Registre québécois du cancer, and the Canadian Vital Statistics database. Incidence and mortality rates and 95% confidence intervals were calculated per year and per geographic area. Rates were plotted using linear regression models to assess trends over time. Overall data were mapped using Microsoft Excel mapping software (Redmond, WA, U.S.A.) to identify case clusters across Canada. Results: Approximately 22,625 patients were diagnosed with fl during 1992-2010. The age-standardized incidence rate of this malignancy in Canada was 38.3 cases per million individuals per year. Geographic analysis demonstrated that a number of Maritime provinces and Manitoba had the highest incidence rates, and that the provinces of Nova Scotia and Quebec had the highest mortality rates in the nation. Regional data demonstrated clustering of fl within cities or regions with high herbicide use, primary mining, and a strong manufacturing presence. Conclusions: Our study provides a comprehensive overview of the fl burden and its geographic distribution in Canada. Regional clustering of this disease in concentrated industrial zones strongly suggests that multiple environmental factors might play a crucial role in the development of this lymphoma.