Topical photodynamic therapy of murine non-melanoma skin carcinomas with aluminum phthalocyanine chloride and a diode laser: pharmacokinetics, tumor response and cosmetic outcomes.

BACKGROUND/PURPOSE: Topical photodynamic therapy (PDT) is potentially useful for the treatment of non-melanoma skin cancer and other skin diseases. We investigated the therapeutic effects of PDT using topical application of aluminum phthalocyanine chloride (AlClPc) and a diode laser emitting at 670 nm in murine non-melanoma skin carcinomas.

METHODS

AlClPc solution (0.7% w/v) was applied to tumors in mice for 1-6 h. The penetration depth and the optimum drug-light interval were assessed using pharmacokinetic studies. Then, PDT was performed on a murine model of non-melanoma skin cancer using seven different combinations of therapeutic parameters (fluence rate and energy dose).

RESULTS

Pharmacokinetic studies revealed that AlClPc was absorbed 40 times more and penetrated 19 times deeper in tumors than normal skin. PDT using AlClPc (0.7% w/v) and a diode laser (75 mW/cm(2), 150 J/cm(2)) resulted in complete tumor remission in 60% of the mice, excellent cosmetic outcomes and growth retardation of tumors with partial remission.

CONCLUSIONS

The results indicate that AlClPc-PDT is an effective treatment for non-melanoma skin carcinomas in experimental mouse models.