Management of Keratoacanthoma: 157 Tumors Managed With Surgery or Intralesional Methotrexate.

BACKGROUND Keratoacanthomas (KAs) are common tumors of squamous cell origin that grow rapidly and may regress; however, differentiation from an aggressive squamous cell carcinoma is problematic. OBJECTIVE To report the authors' experience in managing KA with intralesional methotrexate (MTX) or surgical excision. MATERIALS AND METHODS The authors collected data on 157 tumors (136 patients) over 6 months from a single institution. RESULTS There were 73 tumors (54 patients) treated with intralesional MTX. There were 9 tumors that did not resolve with intralesional MTX (88% cure). Nonresolving tumors were excised with no recurrences or complications. In all 9 cases, the nonresolving tumors were of the same size or smaller after MTX. Of the 73 tumors treated with MTX, 29 tumors (11 patients) were multiple KAs. All 29 tumors resolved (100% tumor clearance). There were no complications in any of the MTX-treated patients. Tumor clearance was defined by clinical resolution for a minimum of 6 weeks without a recurrence. There were 84 tumors (83 patients) treated with surgical excision. There were no complications and no recurrences (100% cure) with surgery. CONCLUSION Intralesional MTX may be considered as the initial treatment for solitary KA, multiple KA, or in poor surgical candidates.