Clin Transl Oncol. 2026 Jun 6. doi: 10.1007/s12094-026-04388-4. Online ahead of print.
ABSTRACT
BACKGROUND: Tattoo inks may contain carcinogenic compounds, and pigment migration to lymphatic tissues raises concerns regarding potential cancer risk. Epidemiological evidence remains inconclusive.
OBJECTIVES: To assess the association between tattoo exposure and the incidence of skin cancer and hematological malignancies.
METHODS: PubMed, Embase, and the Cochrane Library were searched from inception to January 2026 for cohort and case-control studies comparing cancer incidence in tattooed versus non-tattooed adults. Random-effects meta-analyses using restricted maximum-likelihood estimators were performed to pool odds ratios (ORs) with 95% confidence intervals (CIs). Heterogeneity was quantified using I2 statistics. Risk of bias was assessed using ROBINS-E, and certainty of evidence was evaluated with GRADE. Leave-one-out sensitivity analyses were conducted.
RESULTS: Seven observational studies including 140,841 participants were analyzed. Tattoo exposure was not associated with overall skin cancer (OR 0.92; 95%CI 0.83-1.04; I2 = 0%; p = 0.179). Stratified analyses by number of tattoo sessions showed no significant associations: one session (OR 1.08; 95%CI 0.55-2.12; I2 = 92.4%), two-to-three sessions (OR 0.90; 95%CI 0.62-1.32; I2 = 63.2%), and ≥ 4 sessions (OR 0.70; 95%CI 0.29-1.70; I2 = 88.5%). For hematological malignancies, pooled analysis showed no significant association (OR 1.02; 95%CI 0.78-1.32; I2 = 64.9%; p = 0.910). Subtype analyses were non-significant: non-Hodgkin lymphoma (OR 1.00; 95%CI 0.73-1.36; I2 = 3.7%), Hodgkin lymphoma (OR 1.19; 95%CI 0.59-2.40; I2 = 91.7%), diffuse large B-cell lymphoma (OR 0.90; 95%CI 0.57-1.44; I2 = 61.7%), T-cell lymphoma (OR 1.07; 95%CI 0.61-1.88; I2 = 0%), and follicular lymphoma (OR 0.99; 95%CI 0.72-1.36; I2 = 1.9%). Sensitivity analysis excluding one influential study rendered the association for overall hematological malignancies statistically significant (OR 1.20; 95%CI 1.05-1.39; I2 = 0%). Certainty of evidence ranged from low to moderate.
CONCLUSIONS: Tattoo exposure was not associated with increased skin cancer risk and showed no significant association with hematological malignancies in primary analyses. A significant association emerged only after sensitivity analysis, warranting cautious interpretation and further prospective investigation.
PMID:42250187 | DOI:10.1007/s12094-026-04388-4
