BACKGROUNDBasal cell carcinomas (BCCs) are usually treated with ablative procedures. A nonsurgical treatment alternative would be of value in selected patients.OBJECTIVEWe evaluated the safety and efficacy of a new preparation for intralesional sustained-release chemotherapy with MPI 5003, 5-Fluorouracil Therapeutic Implant, for treatment of BCCs.METHODSTwo doses of intralesional MPI 5003 (0.25 and 0.5 ml) were compared in a double-blind study of 20 patients with biopsy-proven BCC. One BCC per patient was treated weekly for up to 6 weeks and followed up monthly for 3 months until excisional biopsy for histologic examination. Before excision the cosmetic appearance of the test site was graded.RESULTSEighty percent of 10 BCCs treated with 0.5 ml of MPI 5003 had histologically confirmed cures as compared with 60% of 10 tumors treated with the lower dose (0.25 ml). Cosmetic assessments before excision were typically good to excellent. No systemic side effects occurred.CONCLUSIONResults indicate the potential of MPI 5003 for targeted local chemotherapy for BCC.