Familial adenomatous polyposis: a case report

Abstract

Abstract Background Familial adenomatous polyposis is characterized by the presence of multiple colorectal adenomatous polyps and caused by germline mutations in the tumor suppressor gene and adenomatous polyposis coli, located on chromosome 5q21–q22. Familial adenomatous polyposis occurs in approximately 1/10,000 to 1/30,000 live births, and accounts for less than 1% of all colorectal cancers in the USA. It affects both sexes equally and has a worldwide distribution. The incidence of colon cancer in low- and middle-income countries is rising. In addition to the increasing incidence, lack of early detection and impeded access to optimal multidisciplinary treatment may worsen survival outcomes. Developing quality diagnostic services in the proper health context is crucial for early diagnosis and successful therapy of patients with colorectal cancer, and applying a resource-sensitive approach to prioritize essential treatments on the basis of effectiveness and cost-effectiveness is key to overcoming barriers in low- and middle-income countries. We report a case of familial adenomatous polyposis presenting as adenocarcinoma with multiple colorectal adenomatous polyps. The diagnosis of familial adenomatous polyposis was made by the presence of numerous colorectal adenomatous polyps and family history of colonic adenocarcinoma. Due to its rarity, we decided to report it. Case presentation A 22-year-old Ethiopian female patient presented to Addis Ababa University College of Health science, Addis Ababa, Ethiopia with rectal bleeding. Abdominopelvic computed tomography scan was done and showed distal rectal asymmetric anterior wall thickening in keeping with rectal tumor. Colonoscopy was done and she was diagnosed to have familial adenomatous polyposis with severe dysplasia. In the meantime, colonoscopy guided biopsy was taken and the diagnosis of adenocarcinoma with familial adenomatous polyposis was rendered. For this, total proctocolectomy was carried out. On laparotomy there was also incidental finding of left ovarian deposition for which left salpingo-oophorectomy was done, and 4 weeks after surgical resection, the patient was started on oxaliplatin, leucovorin, fluorouracil chemotherapy regimen. Conclusion In the clinical evaluation of a patient with rectal bleeding, familial adenomatous polyposis must be considered as a differential diagnosis in subjects having family history of colonic adenocarcinoma for early diagnostic workup, management, family genetic counseling, and testing.

Keywords

• Adenomatous polyposis coli
• Colorectal adenocarcinoma
• Familial adenomatous polyposis
• Low- and middle-income countries