Familial adenomatous polyposis (FAP) is a rare, hereditary disease whose main characteristic is the presence of a large number of polyps in the colon and rectum, which, in the absence of timely treatment, 100% progresses to colorectal cancer. The early diagnosis of this condition is the pillar of the prevention of complications. We present the case of a patient with a low digestive tract syndrome, without previous diagnosis, who after a careful review of clinical and family history, the diagnosis of PAF and later colorectal cancer, is reached. A review of the literature on current advances and recommendations on this disease is made.