COMPARATIVE ASSESSMENT OF THE EFFICACY OF PHOTODYNAMIC THERAPY OF BASAL CELL SKIN CANCER WITH THE INTRALESIONAL ADMINISTRATION OF RADACHLORIN AND FOTODITAZIN

Background: Photodynamic therapy (PDT) is increasingly used for non-invasive destruction of basal cell skin cancer mediated by a photochemical reaction. There is no evidence-based data on its efficacy. Aim: To compare the objective response of basal cell skin cancer of various clinical types, stages, histological types, course and localization to PDT with the intralesional administration of photosensitizers Radachlorin and Fotoditazin. Materials and methods: From March 2007 to March 2010, the study recruited 74  patients with primary and relapsing solid basal skin cancer (ulcerated, 40.5%  of patients, superficial, 24%, nodular, 21.5%, scleroderma-like, 14%), stage  Ι–ΙI (mostly Т₂N₀M₀); with localization that was unfavorable in terms of relapses and inconvenient for treatment application. The tumors were of a uniform complex histological type and of a morphea type. The patients were administered one course of PDT with an intralesional administration of chlorine photosensitizers. The group I (n=45) was administered Radachlorin (0.5–1 mL per 1 cm² of the tumor surface), group II (n=34) was administered Fotoditazin (0.3–0.5  mL per 1  cm² of the tumor surface). For all patients the light dose was chosen at 300 J/cm², the light source being the medical laser device LAMI with a wave length of 662±3 nm, class II А. Clinical and cytological regression of the lesions at 3 months after treatment was chosen as a  primary study endpoint. The secondary endpoints were a  stable clinical and cytological response at 12 months after treatment. Thereafter, a relapse-free period was assessed annually up to 5 years after treatment. In addition, adverse reactions to treatment were registered up to 2 months and cosmetic results were assessed at 12 months after PDT. The treatment results were assessed in all patients. Results: Complete regression of basal cell skin cancer was found in 43 (95.5%) of patients from the group I  and in 31  (91.2%) patients from the group II. Partial regression was seen in 2 (4.5%) and 3  (8.8%) of patients, respectively; these patients were subsequently cured by repeated courses of PDT. In both groups, there was no difference in the early treatment results in patients with various clinical forms of basal cell skin cancer at Т₁N₀M₀ (p>0.05). There was a  significant improvement in the treatment results for the ulcer type of the tumor at stage T₂N₀M₀: 92.8%  in the group  I  and 77.8% in the group II (р<0.05). The long-term follow-up  showed  a  5-year  relapse-free  disease  in 42 (97.7%) of 43 cured patients of the group I and in 30 (96.8%) of 31 patients in the group II. Adverse events  were  seen  in  all  patients;  however,  they were  limited  to  short-term  unavoidable  adverse reactions such as skin hyperemia, edema, exudation, paresthesia and pain. Eight (8) per cent of patients from the group I and 6% from the group II had  their  blood  pressure  values  increase.  An  excellent  and  good  cosmetic  result  after  PDT  was observed in the majority of patients (74.4% in the group  I  and  77.4%  in  the  group  II).  Conclusion: PDT with the intralesional administration of pho- tosensitizers Radachlorin and Fotoditazin is an effective treatment approached for any clinical and morphological type of basal cell skin cancer. It is associated with minimal adverse reactions and has an acceptable cosmetic result.