- colocrectal polyps
- familial colic polyposis
- inflammatory bowel disease
- familial predisposition
- Lynch syndrome
Colorectal polyps represent a frequent situation in the gastroenterological practice, almost 10% of people 50 years - old and up to 30% of people over 70 years present colonic polyps. These polyps may be adenomatous (adenoma) and hyperplastic.
Adenomatous polyps (real polyps) are of many histological types: tubular, tubulo - villous and villous. The villous polyps have the most increased potential of malignity. The hyperplasic (inflammatory) polyps have no malignant potential.
The evolution of polyps towards malignity seems to be linked to genetic factors (familial), metabolic factors (the co- carcinogen effect of billiary acids) and alimentary factors (the negative effect of lack of vegetables and fibers). The bigger the polyps are (generally over 2 cm diameters), the more numerous and the more severe dysplasia is found at biopsy, the highest is their malignant potential. Starting from these data concerning the relationship polyp - neoplasia, searching polyps by colonoscopy and the endoscopic polypectomia has become a necessity, because it is the best prophylaxis of rectocolic neoplasia.
Familial colic polyposis represents a pathological situation with a genetic character, defined by the presence of more than 100 polyps in the rectum and colon, appearing before the age of 30 years. The genetic transmission is autosomal - dominant and the evolution of polyps to cancer is the rule. Therefore, it becomes a necessoty to check - out actively the transmission is autosomal - dominant and the evolution of polyps to cancer is the rule. Therefore, it becomes a necessity to check - out actively the transmission in the affected families and the most precociously total colectomy, before the malignization.
Inflammatory bowel diseases with prolonged evolution increase the risc of colon neoplasm. This risk is of approx. 10% after 25 years of evolution in ulcero - hemorrhagic rectocolitis (becoming significant after more than 10 years of evolution). The risk is smaller in Chron's disease with prolonged evolution.
Familial predisposition represents an increased risk for the descendants of a family with colon cancer (the frequency of cancer is 2-3 times bigger in first - degree relatives).
The Lynch syndrome or the hereditary nonpolypoidal colorectal cancer (without the intermediate state of polyp and with important hereditary involvement) is characterized by presence in more members of a family, the apparition of cancer at young age and frequently associates other neoplasms (the most eften ovary and endometer).
The Amsterdam criteria for diagnosis of Lynch syndrome are at least 3 members of a family with diagnosis of colonic carcinoma, one of which must be a first-degree relative, in a generation; the transmission be done at two succesive generations and at least one of the casees to be diagnosed before 50 years.
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