The aetiology of AIN is intricately linked with human papilloma viruses. The pathological processes involved in the progression of AIN are becoming clearer but the natural history, particularly the rate of progression to invasive cancer, remains unknown. There is no standard management for AIN and this is mainly due to difficulties in both diagnosis and treatment. A variety of treatment options have been tried with varying success. Surgery is associated with significant recurrence, particularly in HIV-positive patients. Non surgical approaches with imiquimod, photodynamic therapy and vaccination are appealing, and further work is required. Long-term follow-up of these patients is essential until the natural history of AIN becomes clearer.

Early involvement of a centre with immunological expertise combined with aggressive management of complications significantly improves morbidity and mortality from this rare condition.

These results show a high yield of endosonographic abnormalities in patients who experience symptoms after haemorrhoidectomy. In particular, occult sphincter injury as a cause of incontinence in these patients can frequently be demonstrated.

No abstract

The introduction of 3-dimensional conformal radiation therapy and intensity modulated radiation therapy has been the most significant advance in reducing radiation morbidity.