Located approximately halfway along the anus, the dentate line marks the transition from the squamous epithelium to the intestinal mucosa. Clin Colon Rectal Surg. N Engl J Med. Mullen et al 83 found that various independent favorable prognostic factors for anal cancer which include recurrence as compared to persistence after chemo-radiation when salvage is potentially curative , absence of lymph node involvement at salvage, and negative resectional margins.
Their report was based upon retrospective analysis of 26 cases of anal margin SCC who were cured with RT between and at University of Florida. State-of-the-art imaging with magnetic resonance imaging MRI using phased-array coils and volumetric multidetector computed tomography CT provides detailed visualisation of anal disorders, identification and extent assessment of neoplastic tissue, detection and characterisation of nodal and visceral metastases. Malignant melanoma arising from a perianal fistula and harbouring a BRAF gene mutation: Above the dentate line, the venous blood drains through the terminal branches of the superior rectal vein into the inferior mesenteric vein and portal system, and below the dentate line via the inferior rectal vein into the pudendal vein which itself drains into the internal iliac vein.