Local radiotherapy in the management of squamous carcinoma of the anus.

This paper describes the results of treating 74 patients with squamous cell carcinoma of the anal canal and perianal skin using interstitial radiotherapy as primary treatment. This technique does not involve irradiation of regional lymph nodes. The local control rate for patients with tumours smaller than 5 cm and with negative inguinal nodes was significantly better than for the remaining patients (64 versus 23 per cent). Only 3 of 41 patients with tumours less than 5 cm diameter had clinically significant nodes at presentation, while in 33 patients with tumours larger than 5 cm there were 6 with involved nodes at presentation. Local treatment using interstitial radiotherapy is suggested as useful primary treatment for small, node-negative carcinomas, with surgery held in reserve for failures.