To the Editor.—
In their article entitled "Psoriasis Induced at the Injection Site of Recombinant Interferon Gamma," Fierlbeck et al1 reported the occurrence of punctiform psoriasis at the site of subcutaneous injection of interferon gamma in patients with psoriatic arthritis.We observed the development of a psoriasis plaque at the site of injection in a patient receiving recombinant interferon beta for intralesional treatment of a basal cell carcinoma. Our patient, a 75-year-old man, had suffered since his youth from chronic stationary psoriasis, and had been treated with arsenic in the 1940s. For the last 10 years he developed multiple basaliomas that were of both the nodular and the superficial erythematous type on the face and trunk. Several tumors have been excised or treated with X-ray therapy or locally applied fluorouracil. Both interferons, alfa and beta, have been shown to be effective in the treatment of basal cell carcinoma.2,3