Risk of skin cancer after ultraviolet phototherapy in patients with vitiligo: a systematic review and meta-analysis

Summary Background Although ultraviolet (UV) phototherapy is an effective treatment for vitiligo, its effect on the risk of skin cancer remains controversial. Aim To investigate the association between UV phototherapy and skin cancer risk in patients with vitiligo. Methods A systematic review was performed for studies published before 5 May 2021 in the PubMed, Embase, Web of Science and Cochrane Library databases. The primary outcome was the association of UV phototherapy with the risk of skin cancer in patients with vitiligo. A meta-analysis with a random-effects model was conducted. Results Five retrospective cohort studies covering a total of 228 607 patients with vitiligo (110 038 who had been treated with UV phototherapy and 118 569 patients who had not) were included in the meta-analysis. The risk of nonmelanoma skin cancer [Mantel–Haenszel risk ratio (MHRR) = 0.95; 95% CI 0.44–2.05] and melanoma (MHRR = 1.11; 95% CI 0.33–3.82) did not significantly increase after phototherapy in patients with vitiligo. In the subgroup analysis, we also found no significant association between phototherapy with narrowband UVB phototherapy specifically and risk of skin cancer in patients with vitiligo. There was no significant difference in risk of skin cancer between patients from Europe and those from East Asia and the risk was not affected by the number of narrowband UVB phototherapy sessions. Conclusions The findings of this systematic review and meta-analysis suggest that UV phototherapy is a safe treatment for vitiligo with no significant risk of skin cancer.