Overview
- Using national registers, researchers identified 2,880 melanoma cases from 2017 and 2,821 squamous cell carcinoma cases from 2014–2017, each matched to three controls.
- Questionnaires captured tattoo status, timing relative to diagnosis, size, and body location to establish exposure before cancer onset.
- Analyses adjusted for sun exposure, tanning bed use, smoking, education, income, marital status, skin type, pigmentation, age, and sex to reduce confounding.
- No association was found for squamous cell carcinoma, and melanoma risk did not increase with larger tattoo size.
- A stronger effect was suggested among people tattooed for more than ten years, though small subgroup numbers limit certainty, and authors call for long-term studies and better tattoo recording in health records.