Stage I colon cancer that spreads into a colovesical fistula-mediated bladder due to crohn's disease: A case report

Abstract

Introduction: Colovesical fistulas are one of the most frequent complications in fistulizing Crohn's disease. Fistulizing Crohn's disease and tumor coexistence may lead to tumor spread through the fistula. Case report: In this study, a 62-year-old male patient with colon cancer spreading to bladder mucosa through the colovesical fistula due to Crohn's disease is presented. He was treated and followed up for Crohn's disease and in the routine follow-up colonoscopy, a mass was observed in sigmoid colon. Computed tomography demonstrated the mass as a local disease. The patient underwent both left hemicolectomy and due to intraoperative colovesical fistula, subsequently, fistulectomy. Pathologic evaluation revealed stage 1 adenocarcinoma of the colon. Transurethral resection was performed for postoperative evaluation and a mass was detected and resected in the bladder. Pathologic findings of resected specimens were consistent with metastasis of adenocarcinoma of the colon. The clinical features, diagnosis and treatment data were analyzed retrospectively and it was thought that the existing tumor spreads to the bladder through the colovesical fistula due to no invasion into the muscularis propria layer of the bladder. Management and outcome: Since muscle invasion was not detected in the bladder after TUR-T, cystectomy was not planned. 8 cycles of systemic adjuvant chemotherapy (Oxaliplatin and Capecitabine) were planned for 6 months. Gastroenterology consultation was requested for Crohn's disease treatment. It was recommended to discontinue azathioprine and continue with adalimumab therapy. Discussion: Colovesical fistula may develop in Crohn's disease that is not in remission and the fistulae can lead the metastasis of tumors.

Keywords

• Crohn's disease
• colon cancer
• colovesical fistula