Does intermittent sun exposure cause basal cell carcinoma? a case-control study in Western Australia

Int J Cancer. 1995 Feb 8;60(4):489-94. doi: 10.1002/ijc.2910600411.


Our report deals with the relationship of pattern and timing of sun exposure to basal cell carcinoma (BCC) in a population-based case-control study conducted in Western Australia in 1988. The main measure of intermittent exposure was based on the amount of exposure on non-working days relative to that over the whole week. Outdoor recreational activities, holidays and sunburn were also considered to be markers of intermittent exposure. We observed a statistically significant increase in risk of BCC with increasing proportion of weekly sun exposure obtained at the weekend, especially in late teenage (OR = 3.9, 95% CI 1.9-7.8 for maximum intermittency of exposure), exposure of the site of skin cancer during holidays (OR = 1.9, 95% CI 1.1-3.1 for the highest exposure quarter) and sunburn to the site (ORs of 1.8 for 3-10 and 1.5 for 11+ sunburns in a lifetime). Risk of BCC increased substantially with increasing intermittency in poor tanners but not at all in good tanners. Our data suggest that a particular amount of sun exposure delivered in infrequent, probably intense increments will increase risk of BCC more than a similar dose delivered more continuously over the same total period of time.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age Factors
  • Carcinoma, Basal Cell / epidemiology
  • Carcinoma, Basal Cell / etiology*
  • Case-Control Studies
  • Dose-Response Relationship, Radiation
  • Environmental Exposure / adverse effects*
  • Female
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Odds Ratio
  • Protective Clothing
  • Risk Factors
  • Skin Neoplasms / epidemiology
  • Skin Neoplasms / etiology*
  • Skin Pigmentation
  • Sunburn / epidemiology
  • Sunlight / adverse effects*
  • Sunscreening Agents
  • Time Factors
  • Western Australia / epidemiology


  • Sunscreening Agents