The registry of digestive tract tumours established for the department of Côte-d'Or was used to study the incidence and the treatment of squamous cell cancer of the anal canal. In the course of 7 years (1976-1982), 45 new cases of anal canal cancer were recorded. Age standardized rates using world standard population are 1.3/100,000 for females, 0.3/100,000 for males. As compared to other cancer registries, Côte-d'Or is in the high range for females, in the average range for males, the cases included 44% with T1-T2 tumours (less than 4 cm), 47% with T3-T4 tumours (more than 4 cm) and 9% unknown (Tx). Lymph node involvement was found in 1/3 of cases, metastatic disease in 11%. Six patients were treated by local excision, 13 by abdomino-perineal resection (combined with postoperative radiotherapy in 5 cases), 20 by radiotherapy (combined with a derivation in 2 cases) and 6 by symptomatic treatment. For T1-T2 normal anal function was preserved in 79% of cases. The 5 year local recurrence rate for curative treatment was 44%. The 5 year observed survival rate was 42.6%; the 5 year relative survival rate was 53.3%. The survival was related to the age, to the sex, to the size of the tumour, and to the nodal status.