BACKGROUND:Topical photodynamic therapy (PDT) is a widely applied treatment for basal cell carcinoma (BCC). PDT-induced immunosuppression leading to reduced antitumour immune responses may be a factor in treatment failure. OBJECTIVES: To examine the impact of topical PDT on leucocyte trafficking following clinical treatment of BCC. METHODS:Superficial BCCs in eight white caucasian patients were treated with methyl aminolaevulinate (MAL)-PDT. Biopsies for immunohistochemical assessment were taken from BCCs pre-PDT, 1 h and 24 h post-PDT and from untreated healthy skin. RESULTS: Treatment of BCC with MAL-PDT produced a rapid neutrophil infiltration, commencing by 1 h and significantly increased at 24 h post-PDT (P < 0·05 compared with baseline). An associated increase in the number of blood vessels expressing E-selectin was observed at 1 h and 24 h post-PDT (both P < 0·05 compared with baseline). In contrast, the number of epidermal Langerhans cells fell sharply by 1 h post-PDT, and remained significantly reduced at 24 h post-PDT (both P < 0·05 compared with baseline). CONCLUSIONS: Reduction of Langerhans cells during clinical treatment of BCC might potentially impact negatively on antitumour responses through reduced activation of tumour-specific effector cells. Investigation of modified PDT protocols with the aim to minimize immunosuppressive effects while maintaining antitumour efficacy is warranted.
RCT Entities:
BACKGROUND: Topical photodynamic therapy (PDT) is a widely applied treatment for basal cell carcinoma (BCC). PDT-induced immunosuppression leading to reduced antitumour immune responses may be a factor in treatment failure. OBJECTIVES: To examine the impact of topical PDT on leucocyte trafficking following clinical treatment of BCC. METHODS: Superficial BCCs in eight white caucasian patients were treated with methyl aminolaevulinate (MAL)-PDT. Biopsies for immunohistochemical assessment were taken from BCCs pre-PDT, 1 h and 24 h post-PDT and from untreated healthy skin. RESULTS: Treatment of BCC with MAL-PDT produced a rapid neutrophil infiltration, commencing by 1 h and significantly increased at 24 h post-PDT (P < 0·05 compared with baseline). An associated increase in the number of blood vessels expressing E-selectin was observed at 1 h and 24 h post-PDT (both P < 0·05 compared with baseline). In contrast, the number of epidermal Langerhans cells fell sharply by 1 h post-PDT, and remained significantly reduced at 24 h post-PDT (both P < 0·05 compared with baseline). CONCLUSIONS: Reduction of Langerhans cells during clinical treatment of BCC might potentially impact negatively on antitumour responses through reduced activation of tumour-specific effector cells. Investigation of modified PDT protocols with the aim to minimize immunosuppressive effects while maintaining antitumour efficacy is warranted.
Authors: Francesco Borgia; Roberta Giuffrida; Emanuela Caradonna; Mario Vaccaro; Fabrizio Guarneri; Serafinella P Cannavò Journal: Biomedicines Date: 2018-01-29