Polyp (medicine)

Overview
A polyp is an abnormal growth of tissue (tumor) projecting from a mucous membrane. If it is attached to the surface by a narrow elongated stalk it is said to be pedunculated. If no stalk is present it is said to be sessile. Polyps are commonly found in the colon, stomach, nose, sinus(es), urinary bladder and uterus. They may also occur elsewhere in the body where mucous membranes exist like the cervix and small intestine.

Colorectal polyp
Colon polyps are uncommonly associated with symptoms. Occasionally rectal bleeding, and on rare occasions pain, diarrhea or constipation may occur because of colon polyps. Colon polyps are a concern because of the potential for colon cancer being present microscopically and the risk of benign colon polyps transforming with time into colon cancer. Since most polyps are asymptomatic, they are usually discovered at the time of colon cancer screening with either digital rectal exam (DRE), flexible sigmoidoscopy, Barium enema, colonoscopy or virtual colonoscopy. The polyps are routinely removed at the time of colonoscopy either with a polypectomy snare (P.Deyhle, 1970) or with biopsy forceps. If an adenomatous polyp is found with flexible sigmoidoscopy or if a polyp is found with any other diagnostic modality, the patient must undergo colonoscopy for removal of the polyp(s). Even though colon cancer is usually not found in polyps smaller than 2.5 cm, all polyps found are removed since the removal of polyps reduces the future likelihood of developing colon cancer. When adenomatous polyps are removed, a repeat colonoscopy is usually performed in three to five years.

Most colon polyps can be categorized as sporadic.

Inherited Polyposis Syndromes

 * Familial adenomatous polyposis
 * Peutz-Jeghers syndrome
 * Familial polyposis coli
 * Turcot syndrome
 * Juvenile polyposis syndrome
 * Cowden disease
 * Ruval-Caba-Myhre-Smith syndrome

Non-inherited Polyposis Syndromes

 * Cronkhite-Canada disease

Types of colon polyps

 * malignant polyp
 * Adenomatous
 * Hamartomatous
 * Hyperplastic
 * Inflammatory

Endometrial polyp
An endometrial polyp or uterine polyp is a polyp or lesion in the lining of the uterus (endometrium) that takes up space within the uterine cavity. Commonly occurring, they are experienced by up to 10% of women. They may have a large flat base (sessile) or be attached to the uterus by an elongated pedicle (pedunculated). Pedunculated polyps are more common that sessile ones. They range in size from a few millimeters to several centimeters. If pedunculated, they can protrude through the cervix into the vagina. Small blood vessels may be present in polyps, particularly large ones.

Cervical polyp
A cervical polyp is a common benign polyp or tumour on the surface of the cervical canal. They can cause irregular menstrual bleeding but often show no symptoms. Treatment consists of simple removal of the polyp and prognosis is generally good. About 1% of cervical polyps will show neoplastic change which may lead to cancer. They are most common in post-menstrual, pre-menopausal women who have given birth.