Narrow-band UV-B (TL-01) Phototherapy Exposure and Skin Cancer Risk: A Nested Case-control Study

Authors

  • Petra Åkerla Department of Dermatology, Tampere University Hospital, Wellbeing Services County of Pirkanmaa, Tampere, Finland; Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland https://orcid.org/0009-0004-2679-0925
  • Eero Pukkala Health Sciences Unit, Faculty of Social Sciences, Tampere University, Tampere, Finland; Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research, Helsinki, Finland https://orcid.org/0000-0001-9536-6440
  • Mika Helminen Health Sciences Unit, Faculty of Social Sciences, Tampere University, Tampere, Finland; Health Sciences Unit, Faculty of Social Sciences, Tampere University, Tampere, Finland https://orcid.org/0000-0001-5695-2084
  • Niina Korhonen Department of Dermatology, Tampere University Hospital, Wellbeing Services County of Pirkanmaa, Tampere, Finland; Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland https://orcid.org/0000-0003-2990-679X
  • Toni Karppinen Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland https://orcid.org/0000-0002-8153-8106

DOI:

https://doi.org/10.2340/actadv.v106.adv-2025-0274

Keywords:

basal cell carcinoma, keratinocyte cancer, narrow band UVB radiation, photocarcinogenicity, phototherapy, skin cancer risk

Abstract

Narrow-band TL-01 ultraviolet B phototherapy (TL-01) is generally considered a relatively safe treatment for skin diseases, although conflicting findings have also been reported. This study aimed to evaluate the association between TL-01 exposure and skin cancer risk using a nested case-control design within a Finnish cohort of 4,815 patients treated with TL-01 monotherapy, with subsequent 38 cases of basal cell carcinoma, 13 cases of cutaneous melanoma, and 9 cases of cutaneous squamous cell carcinoma. Four matched controls were selected for each skin cancer case. Personal TL-01 exposure data were obtained from hospital records. Conditional logistic regression was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs). An increased risk for basal cell carcinoma was observed with higher TL-01 exposure (OR per 20 sessions 1.36, 95% CI 1.08–1.72), whereas no association was found for cutaneous melanoma or cutaneous squamous cell carcinoma. In a categorical analysis, with category of 1–29 TL-01 sessions as the reference, the risk of basal cell carcinoma was markedly elevated among patients who received ≥60 sessions (OR 4.16, 95% CI 1.49–11.6). Occupational outdoor work was considered a potential confounder, but it had no effect. Further studies with larger cohorts and longer follow-up are needed to confirm these findings.

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Additional Files

Published

2026-09-09

How to Cite

Åkerla, P., Pukkala, E., Helminen, M., Korhonen, N., & Karppinen, T. (2026). Narrow-band UV-B (TL-01) Phototherapy Exposure and Skin Cancer Risk: A Nested Case-control Study. Acta Dermato-Venereologica, 106, adv–2025. https://doi.org/10.2340/actadv.v106.adv-2025-0274