Background: Nonmelanoma skin cancer (NMSC) is the most common malignancy affecting caucasian populations and has been seeing global increases in incidence for decades.
Objectives: The objective of this study was to determine trends in incidence of NMSC in Alberta, Canada from 1988 to 2007.
Methods: A retrospective analysis of patients from Alberta diagnosed with NMSC from 1988 to 2007 inclusive was conducted with data retrieved from the Alberta Cancer Registry (ACR). Sex-, age- and anatomical location-specific incidence rates and trends were examined.
Results: From 1988 to 2007, there were 66 192 basal cell carcinomas, 19 959 invasive squamous cell carcinomas (SCC) and 12 494 in situ SCC. ACR coding for the 2007 data was not completed at the time of this study; hence, data from this year were not included in the trend analyses. Incidence of NMSC in women has been stable since 2000 [annual percentage change (APC) 0.08, P = 0.88] and has declined in men since 2001 (APC -1.28, P = 0.026). BCC incidence has been stable since 2000 (APC -0.80, P = 0.09). In situ and invasive SCC also showed a trend towards stabilization in 2000 (APC 0.36, P = 0.77) and 1995 (APC 0.01, P = 0.98), respectively. NMSC primarily affects the elderly and is rarely seen in individuals before the age of 40 years. Although the head and neck region was the location most often involved with NMSC (71.1%), it revealed a stabilizing trend, whereas most other anatomical regions demonstrated an increasing NMSC incidence rate.
Conclusions: NMSC incidence in Alberta has stabilized in women and declined in men. As 95-99% of NMSC occurs in patients aged 40 years or older, and with its increased frequency in traditionally clothed areas, the authors recommend regular complete skin examinations starting at 40 years of age.