No evidence for increased skin cancer risk in Koreans with skin phototypes III-V treated with narrowband UVB phototherapy.

Narrowband ultraviolet B (nbUVB) phototherapy is used around the world for the treatment of various skin diseases. However, the carcinogenic risk associated with nbUVB treatment in patients with skin phototypes III-V has not been studied. This retrospective study compared the incidence of skin cancer in Korean patients with skin phototypes III-V treated with nbUVB with that in a control Korean population. A total of 445 nbUVB-treated patients were followed for 1,274 person-years (mean follow-up period 34.4 months). No melanoma cases were detected during the follow-up period. How-ever, one patient developed basal cell carcinoma four months after the start of nbUVB phototherapy. For non-melanoma skin cancer, the expected number of cases was 0.059 and the standardized incidence ratio 17.0 (95% confidence interval 0.4-94.8). There were no statistically significant differences between the nbUVB and control groups. Thus, nbUVB phototherapy using TL-01 lamps seems to be a safe therapeutic modality for patients with skin phototypes III-V.