A 9-year-old boy comes to the office for health screening after his older brother was found to have colonic polyps. The patient is asymptomatic and has no chronic health conditions. He takes no medications and does not use tobacco, alcohol, or illicit drugs. His father died in a motor vehicle collision several years ago and his mother has no medical conditions. Vital signs are within normal limits. The abdomen is soft, nontender, and nondistended without organomegaly, masses, or ascites. Rectal examination is normal with negative stool occult blood. Colonoscopy is performed and several small nondysplastic adenomatous polyps are removed. Genetic testing of the patient is positive for a germline adenomatous polyposis coli gene mutation. Which of the following is the best initial management for this patient?

Question

A 9-year-old boy comes to the office for health screening after his older brother was found to have colonic polyps.  The patient is asymptomatic and has no chronic health conditions.  He takes no medications and does not use tobacco, alcohol, or illicit drugs.  His father died in a motor vehicle collision several years ago and his mother has no medical conditions.  Vital signs are within normal limits.  The abdomen is soft, nontender, and nondistended without organomegaly, masses, or ascites.  Rectal examination is normal with negative stool occult blood.  Colonoscopy is performed and several small nondysplastic adenomatous polyps are removed.  Genetic testing of the patient is positive for a germline adenomatous polyposis coli gene mutation.  Which of the following is the best initial management for this patient?

Quizplus · Accepted Answer

This patient with a family history of colon polyps and a germline mutation in the adenomatous polyposis coli tumor suppressor gene has familial adenomatous polyposis (FAP). Patients with classic FAP have >100 (and sometimes thousands) of polyps and almost universally develop colorectal cancer (CRC) at an early age (eg, age <40) if left untreated. Some patients may have an attenuated form that carries a slightly decreased risk of CRC compared to classic FAP. Due to their exceedingly high risk of CRC, patients with classic FAP (and sometimes attenuated FAP) need an elective total proctocolectomy in their late teens or early twenties. However, in younger patients (such as this 9-year-old boy), surgery is usually delayed in favor of close surveillance with frequent colonoscopy until patients have completed puberty and matured both physically and emotionally. Urgent total proctocolectomy is performed no matter the patient's age in those with CRC or adenomas with high-grade dysplasia; other indications for colectomy include severe symptoms related to colonic neoplasia (eg, hemorrhage) and a significant increase in polyp number during the screening interval (Choice E). (Choices A and D) Colon cancer screening for the general population, which can be accomplished by colonoscopy or annual fecal immunochemical testing (FIT), usually begins at age 45; this is much too late for patients with FAP, who can develop CRC before this age. In addition, FIT is an inadequate screening test for patients with FAP because it is less sensitive for colonic neoplasia than colonoscopy. (Choice B) Regular aspirin or nonsteroidal anti-inflammatory drug use has been associated with reduced incidence of CRC in patients at average risk but does not influence the chances of developing CRC in FAP. Educational objective: Patients with familial adenomatous polyposis have a significantly increased risk of colorectal cancer. Frequent screening with colonoscopy is started in childhood, and elective total proctocolectomy is considered in the late teens or early twenties. References: ACG clinical guideline: genetic testing and management of hereditary gastrointestinal cancer syndromes. (http://www.ncbi.nlm.nih.gov/pubmed/25645574) Surgical treatment of familial adenomatous polyposis: dilemmas and current recommendations. (http://www.ncbi.nlm.nih.gov/pubmed/25469031)

A 9-Year-Old Boy Comes to the Office for Health Screening