Combination of Er:YAG laser and photodynamic therapy in the treatment of nodular basal cell carcinoma

Abstract

Photodynamic therapy (PDT), via topical aminolevulinic acid (ALA) is an effective treatment for basal cell carcinomas not exceeding a depth of 2 mm. This limits the treatment of basal cell carcinoma (non-melanoma skin cancer) to superficial forms and nodular therapy (only in aesthetically desired locations). This paper addresses the effectiveness of reducing tumor mass via initial Er:YAG laser ablation to depths that are therapeutically responsive to PDT with ALA. This study compared three methods for the treatment of recurring nodular basal cell carcinomas (r nBCC). Method A utilized PDT with topical application of ALA methyl ester, method B with solitary Er:YAG laser ablation, and method C combined Er:YAG laser ablation reducing tumor size below 2 mm (method B) with subsequent ALA methyl ester PDT (method A). All three methods were used to treat to each patient, all subjects presenting with three or more basal cell carcinomas in order to eliminate differences in patient responsiveness to treatment. Patients were monitored and interviewed at 3, 6, and 12 month intervals to examine the progress of tumor elimination, aesthetic results as well as the patient's preference of treatment method. In all, 286 patients were treated, of whom 194 were checked at the prescribed intervals and then evaluated. Statistically, the combination therapy demonstrated the most effective treatment at all time intervals, with a final efficacy of 98.97% versus 94.85% (PDT only) and 91.75% (Er:YAG laser only). The combined method also provided the best aesthetic results (scale: 1--best; 4--worst) of 1.23+/-1.23, compared to 1.67+/-0.76 (PDT only) and 1.83+/-0.95 (Er:YAG laser only). Although 67% patients preferred solitary Er:YAG laser treatment over the PDT method (20%) and the combined treatment (13%), because of the simplicity of the treatment, the combination therapy has proven to be both clinically and aesthetically superior. Solitary Er:YAG laser ablation will remain however a fast, effective, and economical treatment alternative for simple manifestations of superficial basal cell carcinoma and has replaced PDT for uncomplicated cases at our facility. The combination of Er:YAG laser ablation and ALA-PDT aspires to be therapy of choice for BCC.