Colon cancer with colovesical fistula: A report of four cases and a literature review.

Colon cancer with colovesical fistula (CVF) is a rare complication of colon cancer that possesses an extremely poor prognosis. Surgical treatment can improve the prognosis. The current study presents four cases of CVF, in which the first two cases were treated conservatively and the other two were treated surgically. The first case presented with intestinal obstruction for 3 days, and computed tomography (CT) was performed. The patient refused surgery and still exhibited lower abdominal pain 11 months later. The second case presented with urinary frequency and urgency that lasted for 2 days, and CT was performed. The patient refused surgery and died 2 months later. The third case presented with fecaluria that lasted for 1 month, and CT, endoscopy and one-stage palliative surgery were performed. The patient was lost to follow-up 5 months later. The fourth case presented with acute urinary tract symptoms for 4 months, and CT, endoscopy and one-stage radical surgery were performed. The patient remained disease-free 10 months later. The four cases reported in the present study not only represent excellent examples of the disease spectrum, but also act as a reminder of the possibility of detecting CVF at an early stage of the disease. The present study discusses the epidemiology of CVF, and presents the pattern of CVF in terms of signs, symptoms and imaging examinations, including CT, cystoscopy and colonoscopy, as well as treatment in the early stage of the disease.