Risk factors for squamous cell carcinoma of the skin in Saskatchewan, Canada.

Completed questionnaires regarding suspected risk factors for skin cancer were completed by 178 cases of SCC of the skin in Saskatchewan, Canada, and 284 age- sex- and location-matched controls. Significant risk factors identified using chi2 analyses were: farming, family history of skin cancer, light eye color, blond or red hair color, skin types I or II, obvious freckles in childhood, history of severe sunburn, and the use of the herbicide 2,4-Dichlorophenoxy acetic acid. The following relative risks were identified: (1) All cases of SCC of the skin and matched controls: agricultural occupation 1.49, history of severe sunburn 1.49. (2) All men with SCC of the skin and matched controls: history of severe sunburn 1.36 (3) All women with SCC of the skin and matched controls: agricultural occupation 1.83, and skin types I or II 1.48. No association was noted on our study between a history of psoriasis and development of SCC. Neither was an association between smoking and SCC found.