Is topical photodynamic therapy with 5-ALA, using Tsai’s protocol, useful in the healing of oral potentially malignant disorders? A systematic review of the literature

Aim The present review was performed in order to assess the effect of topical photodynamic therapy with 5-ALA in pre-malignant lesions, using the Tsai's protocol.Material and methods Studies, using the Tsai's protocol with topical photodynamic therapy with 5-ALA, in oral potentially malignant disorders (oral leukoplakia, oral eryhtroplakia, oral verrucous leukoplakia, oral lichen planus) and with at least 5 months follow-up, were selected. The light source was: 635 nm laser light or LED red light at 635 nm. The main outcome measure was the healing of the potentially malignant disorders evaluated as Complete Response, Partial Response, No Response.Results Of the 12 eligible studies, five studies were included. Seven studies were excluded because they did not followe the Tsai's protocol, 2 because the lesions were analyzed in other studies. The outcomes were: Oral Leucoplakia 7.7% complete response, 50.8% partial response, 41.5% no response; Oral Erythroplakia: 91,7% complete response, 8.3% partial response; Oral Verrucous Hyperplasia 100% complete response.Conclusions Within the limitation of the present systematic review, the selected studies suggested that 5-ALA PDT, using the fractionated Tsai's protocol, had good results in the treatment of oral verrucous hyperplasia, less in erythroplakia and leukoplakia; this could be due to the different epithelial structure of the lesions. Further studies need to be conducted to confirm these data.