screening of colon cancer:

in the general population, they tell to start screening at 50 years of age with the following methods:

    1. colonoscopy and repeat every 10 year

    2. guaiac fecal occult blood test or fecal immunochemical test (FIT) every year 

    3. FIT DNA every 1-3 year

    4. CT Colonography every 5 years.

     5. flexible sigmoidoscopy every 5 years and if combined with FIT, do 10 yearly

In a person with a family history of colon cancer start screening at 40 years of age or 10 years earlier whichever comes first and then repeat every 3-5 years.

whom to consider family history positive?

Before answering this question, first, let us talk about what is an advanced adenomatous polyp is. Advanced polyp means either size of polyp more than 1 cm villous or high-grade dysplasia

Now see the definition of family history below:

1. if First degree relative with colon cancer  or advanced adenomatous polyp diagnosed before 60 year of age.

2. if more than 2 relatives (either first or second degree) are diagnosed (then regardless of age) with colorectal cancer or advanced adenomatous polyp.

in patients with ulcerative colitis, they are told to start screening after 5 years of diagnosis of U.C. and then 5 yearly.

in patient with familial syndrome, start at diagnosis of that syndrome, then 2- 3yearly.

in patient who under went polypectomy and margin was more than 2mm, then do repeat after 2-3 months.

if villous adenoma is found on polypectomy (but no muscle invasion), repeat colonoscopy after 2-3 months.