27517 Mohs micrographic surgery for high-risk cutaneous squamous cell carcinoma

Abstract

While most cutaneous squamous cell carcinomas (cSCCs) are readily cured by surgery, there is a subset of cSCCs that are regarded as high-risk tumors that have an increased propensity to locally recur and metastasize. The data on adjuvant therapy following the surgical resection of high risk SCCs (HR-SCCs) is sparse. To date, there has been no study that has demonstrated the utility of adjuvant radiation therapy after MMS with negative margins. Adjuvant radiation may be employed to treat the primary tumor site after wide local excision to minimize the risk of disease recurrence or spread from single cell disease. However, adjuvant radiotherapy may not be needed with superior margin control afforded by MMS. We sought to determine the incidence of negative outcomes in patients with HR-SCCs of the head and neck who were treated with MMS monotherapy at our institution. We found that the overall recurrence rate of these high-risk tumors was 5.0% (4/75). All four recurrences were graded as BWH T3 tumors, none of the BWH T2 tumors or the BWH T4 tumors were found to recur during the patients’ follow-up. Interestingly, in all of the recurrent tumors, the patient was immunosuppressed and the tumors were located on the scalp. We found that the risk of recurrence was associated with immunosuppression and this association was statistically significant (P = .0025). Hence, adjuvant radiotherapy in most cases of HR-SCCs may not afford any additional benefit after clear margins are obtained with MMS but may be considered in immunosuppressed patients.