TREATMENT OF BASAL-CELL CARCINOMA WITH INTRALESIONAL RECOMBINANT INTERFERON-BETA - A DOSE-FINDING STUDY

Recombinant interferon (IFN)-alpha has been shown to be effective in t he therapy of basal cell carcinoma (BCC). IFN-beta has been reported t o have higher tissue affinity when injected intratumorally owing to a higher content of hydrophobic amino acids. Our purpose was to determin e the lowest dose and frequency of administration of IFN-beta required to bring about a complete remission in BCC in order to find out wheth er IFN-beta would be more effective for intralesional tumor therapy th an IFN-alpha in BCC. Sixty-nine evaluable patients with basal cell car cinoma received intralesional injections of recombinant human IFN-beta for three weeks. The patients were assigned to seven therapy groups. Efficacy (i.e. biopsy verified complete remission) was determined 12 w eeks after the initiation of therapy. Systemic and local side effects were evaluated. Best results were found in the groups treated with 1 o r 0.5 x 10(6) international units (MU) 3 times a week with complete re mission rates of 86% or 64%, respectively. In these groups systemic si de effects occurred in 27% and 37%, respectively. IFN-beta is effectiv e in BCC at a dose of only 0.5 to 1 MU when administered 3 times a wee k for 3 weeks. The higher dose of 1 MU seemed to be more effective. Th us IFN-beta can induce complete remission of BCC at one- to two-thirds of the dose of required IFN-alpha to induce complete remission of BCC and leads to a lower rate of systemic side effects during treatment. Therefore, IFN-beta appears to be superior to IFN-alpha for intralesio nal BCC therapy.