Basosquamous carcinoma: Treatment with Mohs micrographic surgery

BACKGROUND. Basosquamous carcinoma (BSC) is a rare tumor defined as a basal cell carcinoma (BCC) differentiating into squamous cell carcinoma (SCC). It is reported to have a high rate of recurrence with standard wide local excision. The aim of the current study was to report a large series of patients with BSC treated with Mohs micrographie surgery (MMS). METHODS. The prospective, multicenter case series included all patients in Australia treated with MMS for BSC, who were monitored by the Skin and Cancer Foundation Australia between 1993 and 2002. RESULTS. Most of the 178 tumors (95.6%) were located in the head and neck area. Recurrent tumors occurred in 47.8% of patients. The tumors were diagnosed initially as BCC in 87.4% and as SCC in 12.0% of patients. Perineural invasion was recorded in 7.9% of patients with data available. Most of these (69.0%) were previously recurrent tumors. Of 98 patients who completed a 5-year follow-up period after MMS, 4 (4.1%) had disease recurrence. CONCLUSIONS. The low 5-year disease recurrence rate of BSC with MMS emphasized the importance of margin-controlled excision using MMS.