Most cutaneous squamous cell carcinomas (SCCs) of the trunk and extremities are small enough to be cured by simple surgical excision. Because the risk of metastasis of SCCs of the head and neck arising from mucosal surfaces is higher than the risk of metastasis of SCCs arising from cutaneous surfaces, it may be more appropriate to review case reports of the trunk and extremities separately from those of the head and neck when seeking prognostic indicators. A small group of advanced lesions, however, is more difficult to treat and has an increased risk of local recurrence or metastasis and a poorer prognosis. We describe a patient with high-risk cutaneous SCC who is disease-free 1 year after adjuvant radiotherapy subsequent to excision by Mohs micrographic surgery. This report discusses prognostic indicators of cutaneous SCC and suggests adjuvant modalities for the treatment of high-risk disease after surgical excision. Radiotherapy is a rational choice as adjuvant therapy for the treatment of high-risk cutaneous SCC after excision.