Malignant colo-duodenal fistula; case report and review of the literature

BACKGROUND: Colo-duodenal fistula is a rare complication of malignant and inflammatory bowel disease. Cases with malignant colo-duodenal fistulae can present with symptoms from the primary, from the fistula or from metastatic disease. The fistula often results in diarrhoea and vomiting with dramatic weight loss. Upper abdominal pain is usually present as is general malaise both from the presence of the disease and from the metabolic sequelae it causes. The diarrhoea relates to colonic bacterial contamination of the upper intestines rather than to a pure mechanical effect. Vomiting may be faeculant or truly faecal and eructation foul smelling but in the case reports this 'classic' symptomatology was often absent despite a fistula being present and patent enough to allow barium through it. Occasionally patients will present with a gastro-intestinal bleed. CASE PRESENTATION: We present an unusual case of colorectal carcinoma, where a 65 year old male patient presented with diarrhoea and vomiting secondary to a malignant colo-duodenal fistula near the hepatic flexure. Adenocarcinoma was confirmed on histology from a biopsy obtained during the patient's oesophageogastroduodenoscopy, and the fistula was demonstrated in his barium enema. Staging computed tomography showed a locally advanced carcinoma of the proximal transverse colon, with a fistula to the duodenum and regional lymphadenopathy. The patient was also found to have subcutaneous metastasis. Following discussions at the multidisciplinary meeting, this patient was referred for palliation, and died within 4 months after discharge from hospital. CONCLUSION: We present the case, discuss the management and review the literature. Colo-duodenal fistulae from colonic primaries are rare but early diagnosis may allow curative surgery. This case emphasises the importance of accurate staging and repeated clinical examination.