Article

Controlled 15-year trial on screening for colorectal cancer in families with hereditary nonpolyposis colorectal cancer.

Second Department of Surgery, Helsinki University Central Hospital, Helsinki, Finland.
Gastroenterology (Impact Factor: 13.93). 06/2000; 118(5):829-34. DOI: 10.1016/S0016-5085(00)70168-5
Source: PubMed

ABSTRACT Identification of the hereditary nonpolyposis colorectal cancer (HNPCC) syndrome enables prevention of colorectal cancer (CRC) by means of colonoscopy and polypectomies. We evaluated the efficacy of screening in a controlled trial over 15 years.
Incidence of CRC and survival were compared in 2 cohorts of at-risk members of 22 families with HNPCC. Colonic screening at 3-year intervals was arranged for 133 subjects; 119 control subjects had no screening. Genetic testing was offered to subjects in whose families the causative mutation was known.
CRC developed in 8 screened subjects (6%) compared with 19 control subjects (16 %; P = 0.014). The CRC rate was reduced by 62%. In mutation-positive subjects alone, the CRC rates were 18% in screened subjects and 41% in controls (P = 0.02). The decrease resulted from the removal of adenomas in 13 mutation-positive individuals (30%) and in 6 subjects with unknown mutation status (40%). All CRCs in the study group were local, causing no deaths, compared with 9 deaths caused by CRC in the controls. The overall death rates were 10 vs. 26 subjects in the study and control groups (P = 0.003), 4 vs. 12 in mutation-positive subjects (P = 0.05).
Colonoscopic screening at 3-year intervals more than halves the risk of CRC, prevents CRC deaths, and decreases overall mortality by about 65% in HNPCC families.

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