The patient was diagnosed with familial adenomatous polyposis (FAP) after a medical history that showed that most of his predecessors died of tumors. What an abomination! Familial adenomatous polyposis, commonly known as FAP, is an autosomal dominant disease characterized by the growth of hundreds or thousands of polyps in the colorectum. If left unattended, almost 100% of them will develop into colorectal cancer, mainly due to mutations in the adenomatous polyposis gene (APC). Genetic disease, sounds weird and scary. Nowadays, it is more popular to fight for your father, but for FAP, you still have to fight for your family line, so you can avoid a lot of troubles if you come from a better background. But not everyone has a good family without a good family, do we have to leave it to fate. The FAP is actually not as scary as you might think, so let’s learn more about what it is! The common manifestation of FAP is colon polyps, hundreds or thousands of which grow in the colon. Most patients have polyps in childhood, and by the time they reach adolescence, the polyps increase in size and number, causing colorectal bleeding and even anemia, changes in bowel habits, constipation, diarrhea, abdominal pain, palpable abdominal masses, weight loss, etc. In addition to the scourge of the colon, FAP is also found in other parts of the body. 70% of patients have extra-intestinal manifestations, such as congenital hypertrophy of the retinal epithelium The majority of patients with AP have a wide range of extraintestinal manifestations, such as congenital retinal epithelial hypertrophy, bone marrow and dental malformations, duodenal adenomas, fundic gland polyps, adenomas in the gastric sinus, epidermoid cysts and lipomas, sclerofibromas, and other malignancies such as thyroid cancer and hepatoblastoma. Thankfully, however, most extraintestinal manifestations are benign. Although the symptoms of FAP are still typical, there are no uniform clinical diagnostic criteria. However, the diagnosis generally includes the following conditions: the patient has more than 100 colorectal adenomatous polyps (light phenotype FAP usually has 10-100) with an early age of onset; often accompanied by extraintestinal manifestations such as congenital retinal pigment epithelial hypertrophy and sclerofibroma; and autosomal dominant inheritance (patients are found in several generations). The seriousness of FAP lies in its high rate of carcinogenesis, which is often multicentric and more than one, and the high rate of carcinogenesis when FAP is untreated, with adenomatous polyps appearing when the patient is 12 or 13 years old and spreading throughout the large intestine by the age of 20. However, surgical treatment can effectively reduce the risk of cancer, which is a ray of hope for FAP patients. At present, the main surgical methods for FAP patients are: total colectomy + ileorectal anastomosis (TAC/IRA) total colectomy + ileostomy (TPC/EI); total colectomy + ileal pouch-anal tube anastomosis (TPC/IPAA). Different surgical approaches have their own advantages and disadvantages, and the specific choice of which approach should be based on the actual situation of the patient in order to develop the optimal surgical plan. Currently, TAC/IRA surgery is usually recommended for patients with mild phenotype FAP and TPC/IPAA surgery is usually recommended for patients with FAP. In addition, one thing that is particularly important for people with a family history of FAP is early colonoscopic monitoring. The incidence of colorectal cancer in patients with FAP who undergo colonoscopic surveillance is 3-10%, much lower than in patients who do not undergo colonoscopic testing and are seen for the development of symptoms, where the incidence of colorectal cancer is 50-70%. Therefore, genetic testing and colonoscopic surveillance are particularly important. In general, people with FAP or those with a hereditary family history should be vigilant and not wait until symptoms or even irreversible and serious lesions appear before seeking medical attention. Regular medical checkups should be performed for early detection and early management so as to provide effective prevention and early management after lesions are detected to prevent cancer and improve survival rates.