All are risk factors of squamous cell carcinoma except: (A) Ultraviolet radiation, (B) Tar, (C) Tobacco, (D) HPV 18
Answer is D. Ultraviolet radiation, chronic inflammation, and chemical carcinogens (arsenicals, tar) and infection with HPV 5 and 16.There is also evidence that current and previous tobacco use doubles the relative risk of SCC.Ref: Bailey and Love, 27e, page: 606