Childhood cancer trends in a western Canadian province: A population‐based 22‐year retrospective study

Abstract

The objective of this study was to describe children and youth <20 years of age diagnosed with malignant cancer in Alberta, Canada over 22 years. We consider both temporal and geographical variations. The Alberta Cancer registry was used to extract information on cancer diagnoses during April 1, 1982, and March 31, 2004. Data extracted included gender, age at diagnosis, diagnosis, and geographic information. Population data were also obtained and analyses included descriptive summaries, rates, and cluster detection tests. During 22 fiscal years, 2,758 Alberta children and youth were diagnosed with malignant cancer. The average age of diagnosis was 9.6 years. The most common diagnoses were leukemia (24.8%), central nervous system (16.7%), lymphoma (15.8%), and other epithelial neoplasm and melanoma (11.2%). The number of malignant cases varied over year with crude rates of 13.4 per 100,000 in 1982/1983 to 17.3 per 100,000 in 2003/2004. Variation was also seen over diagnosis sub-group and geographic region. Although a relatively rare number of children and youth in Alberta were diagnosed with cancer during the study period, there were suggestions that an increase incidence in childhood cancer occurred in later years and some geographic areas have more cases than expected by chance. Further study is required to see if emerging trends continue and explain higher rate areas.