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Benign Tumor of the Colon and Rectum

Different benign tumours may occur in the rectum and colon but the epithelial tumours are only the common varieties. These benign epithelial tumours of the rectum and the colon are collectively termed as polyps . These are divided into four main groups:
  1. Hemartomatous Polyps
  2. Neoplastic Polyps
  3. Inflammatory Polyps
  4. Metaplastic Polyps
1. Hemartomatous Polyps:
These are local tissue malformations, having no malignant potentials. There are mainly two types:
  1. Juvenile Polyp: The common rectal polyp of the children. There is a spherical mass, usually of the size of a pea, having a long narrow pedicle. The child presents with passage of fresh blood (sometimes with mucous) in the stool. Sometimes the fleshy mass is prolapsed through the anus during defecation. Rarely, following such a prolapse, the pedicle may be tightly caught by the sphincter and auto-amputation of the polyp may occur. Diagnosis is easily made by digital examination and with an anal speculum.

    As the pedicle is long, the tumour can well be delivered thought the anus, the pedicles ligated and the polyp excised. If the tumour is high up or if the pedicle is short, a snare may have to be used.


  2. Peutz-Jeghers Syndrome: This syndrome was first described by Hutchinson in 1896 but later in 1949, the existence of hematopolyp was originally Peutz and later Jegher. This syndrome causes well documented risk of breast cancer, cervix, ovary, fallopian tubes, thyroid glands, lungs, kidneys, gall bladder, bile duct, testicles etc.
    This syndrome is rare in the rectum or colon and is typical of small intestine. Its characteristic features are:
    1. it is familial
    2. there are multiple polyps, particularly in the jejunum (but malignancy never occurs, c.f. colonic polyposis)
    3. there is melanosis of the oral mucosa and the lips.
2. Neoplastic Polyps:
These are actually benign tumours of the large gut. There are mainly two types:
     1. Adenoma
     2. Villous Papilloma
While an adenoma arises from the cells at the depth of crypts of Leiberkuhn, a papilloma originates from the cells at the surface of crypts.

Adenoma: An adenoma (or adenomatous polyp), as compared to the juvenile polyp, is either a sessile or has a tougher stalk and, therefore, cannot be plucked off the rectal wall so easily. The tumour may occasionally turn malignant and should, therefore, be removed by the following procedures:

   1. If there is a pedicle:
  • For growths in the lower two third of the rectum, the tumour can be delivered through the anus, the pedicle transfixed and the growth excised.
  • For growths higher up, a sigmoidoscope has to be used and then the tumour is removed with a snare.
   2. If there is no pedicle i.e. sessile adenoma:
    The tumour has to be fulgurated with a stiff insulated electrode, passed through a sigmoidoscope
Villous papilloma: The surface of the tumour has fine finger like projections i.e. villi. Hence it is called villous papilloma. Like papilloma elsewhere, it has a central connective tissue stroma, on which columnar epithelium is laid down. The tumour may sometimes attain a considerable size.

While papilloma may remain benign throughout, some of them do turn malignant; the chances of malignancy are a little more than with adenomas.

The patient presents with passage of profuse mucous (which may occasionally be as high a 2 – 3 litres a day).

For smaller growth, either excision or diathermy-coagulation of the tumour is the treatment. For large growths, excision of the rectum has to be undertaken.

3. Inflammatory Polyps:
These are so called pseudopolyps because they are not actually tumours and consist of granulation tissue covered with mucosa. They may be found in cases of ulcerative colitis, amoebic colitis and Crohn’s disease. They are usually multiple (pseudopolyposis) .

4. Metastatic Polyps:
They are only sessile mucosal excrescences.

Familial Polyposis of the colon and rectum:
This is a hereditary condition transmitted from both the sexes to both the sexes, characterized by multiple (hundreds) adenomas, scattered over the colon, particularly the sigmoid and often the rectum as well.

If the rectum is free then total colectomy is done and the ileum is anastomosed to rectum. If the rectum is involved as well then a proctocolectomy is undertaken and a permanent terminal ileostomy has to be done.

Familial Adenomatous Polyposis (FAP):
Familial Adenomatous Polyposis includes Gardener’s syndrome, Turcot’s syndrome and familial polyposis.

Familial polyposis: is described above.
Gardener’s syndrome: includes epidermal cysts, bone osteomas and adenomatous polyps in the upper GIT.
Turcot’s syndrome: includes colonic polyposis, intracranial gliomas and medulloblastomas.

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This article has been written by Dr. M. Javed Abbas.
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21:05 21/12/2002