Snapshot quiz 17/6
Authors: Sutton PA, McWhirter D and Walsh C
This 44-year-old man presented with a history of rectal bleeding and tenesmus. Investigation revealed a mid-rectal adenocarcinoma. Examination under anaesthetic, but not previous clinical examination or colonoscopy, revealed the appearances in this photograph. This is histologically proven tumour implantation (arrow) from the more proximally situation middle-third rectal adenocarcinoma, within an idopathic posterior midline fissure in ano. The swab in the anal canal illustrates that this is implantation and not contiguous with the primary tumour. The most appropriate treatment is neoadjuvant chemoradiotherapy followed by abdominoperineal excision and perineal reconstruction.