The major development in the treatment of cancers of the anal canal, over recent years, is the now predominant role of radiotherapy which has replaced amputation surgery as first-line treatment. All stages combined, the average 5-year global survival rate is now 60%, with a local control rate of 70% and good sphincter preservation in the majority of healed patients. However, many questions remain unresolved in these rare cancers: what is the optimal irradiation technique, what is the role of chemotherapy in this very chemosensitive tumour but associated with a low risk of metastases? Amputation surgery still plays an important role, but the exact time at which it should be proposed remains controversial. The rate of inguinal lymph node invasion is approximately 20%. The value of systematic treatment N0 inguinal nodes remains controversial. As for most problems of clinical oncology, only randomized trials rapidly conducted on a large scale will be able to provide an answer to all these questions.