Polyp (medicine)

A polyp is an abnormal growth of tissue<ref>Template:Cite web</ref> projecting from a mucous membrane.<ref>Template:Cite journal</ref> Polyps are commonly found in the colon, stomach, nose, ear, sinus(es), urinary bladder, and uterus.<ref>Template:Cite web</ref><ref>Template:Cite web</ref> They may also occur elsewhere in the body where there are mucous membranes, including the cervix, vocal folds, and small intestine.

If it is attached by a narrow elongated stalk, it is said to be pedunculated; if it is attached without a stalk, it is said to be sessile.<ref>Template:Cite web</ref><ref>Template:Cite web</ref><ref>Template:Cite journal</ref><ref>Template:Citation</ref>

Some polyps are tumors (neoplasms) and others are non-neoplastic,<ref>Template:Cite web</ref><ref>Template:Citation</ref> for example hyperplastic or dysplastic, which are benign. The neoplastic ones are usually benign, although some can be pre-malignant, or concurrent with a malignancy.<ref name=":1">Template:Cite web</ref>

Digestive polyps

Relative incidences by location:

• 
  Incidences and malignancy risks of various types of colorectal polyps<ref>References for diagram are located at: Commons:Template:Pie chart of colorectal polyp etiologies - Source.</ref>
• 
  Relative incidences of gastric polyps<ref>Template:Cite journal</ref>

Polyp	Typical location	Histologic appearance	Risk of malignancy	Picture	Syndromes
Hyperplastic polyp	Colorectal (unless otherwise specified)	Serrated unbranched crypts	if polyps are more than 100		Serrated polyposis syndrome
Hyperplastic polyp of the stomach	Stomach	Elongated, tortuous, and cystic foveolae separated by edematous and inflamed stroma.<ref>Template:Cite journal - Attribution 3.0 Unported (CC BY 3.0) license</ref>			Gastric hyperplastic polyposis
Fundic gland polyp	Fundus of stomach	Cystically dilated glands lined by chief cells, parietal cells and mucinous foveolar cells.<ref>Template:Cite web Topic Completed: 1 November 2017. Minor changes: 11 December 2019</ref>	Very low or none, when sporadic.<ref>Template:Cite web Literature review current through: Sep 2020. | This topic last updated: Feb 14, 2019.</ref>		Fundic gland polyposis
Sessile serrated adenoma	Colorectal	Similar to hyperplastic with hyperserration, dilated/branched crypt base, prominent mucin cells at crypt base	Yes		Serrated polyposis syndrome
Inflammatory	Non-specific	Raised mucosa/submucosa with inflammation	If dysplasia develops		Inflammatory bowel disease, ulcers, infections, mucosal prolapse
Tubular Adenoma (Villous, Tubulovillous)	Colorectal	Tubular glands with elongated nuclei (at least low-grade atypia)	Yes
Traditional serrated adenoma	Colorectal	Serrated crypts, often villous architecture, with cytologic atypia, eosinophilic cells	Yes		Serrated polyposis syndrome
Peutz-Jeghers Polyp	All digestive tract	Smooth muscle bundles between nonneoplastic epithelium, "Christmas tree" appearance	No		Peutz–Jeghers syndrome
Juvenile Polyp	Upper GI tract and colon	Cystically dilated glands with expanded lamina propria	Not inherently, may develop dysplasia		Juvenile polyposis syndrome, identical polyps in Cronkhite–Canada syndrome
Hamartomatous Polyp (Cowden Syndrome)	Mainly colorectal	Variable; classical mildly fibrotic polyp with disorganized mucosa and splaying of muscularis mucosae; also inflammatory, juvenile, lipoma, ganglioneuroma, lymphoid	No		Cowden syndrome
Inflammatory fibroid polyp	All digestive tract	Spindle cells, featuring concentric arrangements around blood vessels, and inflammation rich in eosinophils	none

<ref>Fletcher's Diagnostic Histopathology of Tumors, 3rd Ed..</ref><ref>Sternberg's Diagnostic Surgical Pathology, 5th Ed.</ref>

Colorectal polyp

Template:Main While colon polyps are not commonly associated with symptoms, occasionally they may cause rectal bleeding, and on rare occasions pain, diarrhea or constipation.<ref>Template:Cite web</ref> They are a concern because of the potential for colon cancer being present microscopically, and the risk of benign colon polyps becoming malignant over time.<ref>Template:Cite web</ref> Since most polyps are asymptomatic, they are usually discovered at the time of colon cancer screening. Common screening methods are occult blood test, colonoscopy with a modern flexible endoscope, sigmoidoscopy (usually with the older rigid endoscope), lower gastrointestinal series (barium enema), digital rectal examination (DRE), virtual colonoscopy or Cologuard.<ref name="AGAfive">Template:Citation</ref>

The polyps are routinely removed at the time of colonoscopy, either with a wire loop known as a polypectomy snare (first description by P. Deyhle, Germany, 1970),<ref>Template:Cite journal</ref> or with biopsy forceps. If an adenomatous polyp is found, it must be removed, since such a polyp is pre-cancerous and has a propensity to become cancerous. For certainty, all polyps which are found by any diagnostic modality, are removed by a colonoscopy.

In the US, if a colonoscopy finds polyps that are 10mm or bigger, numerous or abnormal, a repeat colonoscopy may be required (within three years). If one or two are found that are less than 5mm in diameter you may not have to return for a colonoscopy for five or more years. If none are found, a repeat colonoscopy may not be required for 10 years.<ref>Template:Cite web</ref> Most colon polyps can be categorized as sporadic.<ref name=":0">Template:Citation</ref>

Inherited polyposis syndromes

Micrograph of a Peutz–Jeghers colonic polyp – a type of hamartomatous polyp. H&E stain.

• Familial adenomatous polyposis<ref name="Familial Adenomatous Polyposis">Template:Cite web</ref>
• Peutz–Jeghers syndrome
• Turcot syndrome
• Juvenile polyposis syndrome
• Cowden disease
• Bannayan–Riley–Ruvalcaba syndrome (Bannayan–Zonana syndrome)
• Gardner's syndrome
• Serrated polyposis syndrome

Non-inherited polyposis syndromes

• Cronkhite–Canada syndrome

Types of colon polyps

• Malignant
• Hamartomatous
• Hyperplastic
• Inflammatory: Inflammatory fibroid polyp

Adenomatous polyps

Adenomatous polyps, or adenomas, are polyps that grow on the lining of the colon and which carry a high risk of cancer. The adenomatous polyp is considered pre-malignant, i.e., likely to develop into colon cancer.<ref name="A1">Template:Cite web</ref> The other types of polyps that can occur in the colon are hyperplastic and inflammatory polyps, which are unlikely to develop into colorectal cancer.<ref>Template:Cite web</ref>

About 5% of people aged 60 will have at least one adenomatous polyp of 1 cm diameter or greater.<ref name="B2">Template:Cite web</ref> Multiple adenomatous polyps often result from familial polyposis coli or familial adenomatous polyposis, a condition that carries a very high risk of colon cancer.<ref name="Familial Adenomatous Polyposis"/>

Types

Adenomas constitute approximately 10% of digestive polyps. Most polyps (approximately 90%) are small, usually less than 1 cm in diameter, and have a small potential for malignancy. The remaining 10% of adenomas are larger than 1 cm and approach a 10% chance of containing invasive cancer.<ref name="C3">Template:Cite web</ref>

There are three types of adenomatous polyp:

• Tubular adenomas (tube-like shape) are the most common of the adenomatous polyps; they may occur everywhere in the colon and they are the least likely colon polyps to develop into colon cancer
• Tubulovillous
• Villous adenomas are commonly found in the rectal area and they are normally larger in size than the other two types of adenomas. They tend to be non-pedunculated, velvety, or cauliflower-like in appearance and they are associated with the highest morbidity and mortality rates of all polyps. They can cause hypersecretory syndromes characterized by hypokalemia and profuse mucous discharge, and can harbor carcinoma in situ or invasive carcinoma more frequently than other adenomas.

Risks

The risks of progression to colorectal cancer increase if the polyp is larger than 1 cm and contains a higher percentage of villous component. Also, the shape of the polyps is related to the risk of progression into carcinoma. Polyps that are pedunculated (with a stalk) are usually less dangerous than sessile polyps (flat polyps). Sessile polyps have a shorter pathway for migration of invasive cells from the tumor into submucosal and more distant structures, and they are also more difficult to remove and ascertain. Sessile polyps larger than 2 cm usually contain villous features, have a higher malignant potential, and tend to recur following colonoscopic polypectomy.<ref name="D4">Template:Cite web</ref>

Although polyps do not carry significant risk of colon cancer, tubular adenomatous polyps may become cancerous when they grow larger. Larger tubular adenomatous polyps have an increased risk of malignancy when larger because then they develop more villous components and may become sessile.<ref>Template:Citation</ref>

It is estimated that an individual whose parents have been diagnosed with an adenomatous polyp has a 50% greater chance to develop colon cancer than individuals with no family history of colonic polyps.<ref>Template:Cite web</ref> Research suggests approximately 5 percent of colon cancer cases are due to an inherited genetic mutation.<ref name=":0" />

Screening

Screening for colonic polyps as well as preventing them has become an important part of the management of the condition. Medical societies have established guidelines for colorectal screening in order to prevent adenomatous polyps and to minimize the chances of developing colon cancer.<ref>Template:Cite web</ref><ref>Template:Cite web</ref> It is believed that some changes in the diet might be helpful in preventing polyps from occurring, but there is no other way to prevent the polyps from developing into cancerous growths than detecting and removing them.<ref name=":2">Template:Cite web</ref>

Colon polyps as they grow can sometimes cause bleeding within the intestine, which can be detected by an occult blood test. According to American Cancer Society guidelines, people over 50 should have an annual occult blood test. People in their 50s are recommended to have flexible sigmoidoscopies performed once every 3 to 5 years to detect any abnormal growth which could be an adenomatous polyp. If adenomatous polyps are detected during this procedure, a colonoscopy is recommended. Medical societies recommend colonoscopies every ten years starting at age 50 as a necessary screening practice for colon cancer.<ref name="AGAfive"/><ref name="coloscreen">Template:Cite journal</ref> The screening provides an accurate image of the intestine and also allows the removal of the polyp, if found.

Once an adenomatous polyp is identified during colonoscopy, they can be treated with a polypectomy, minimally invasive surgery or in cases with additional risk factors, a total proctocolectomy.<ref name=":1" /> Colonoscopies are preferred over sigmoidoscopies because they allow the examination of the entire colon and can detect polyps in the upper colon, where more than half of polyps occur.<ref>Template:Cite web</ref>

It has been statistically demonstrated that screening programs are effective in reducing the number of deaths caused by colon cancer due to adenomatous polyps. The risk of complications associated with colonoscopies is approximately 0.35 percent, compared to a lifetime risk of developing colon cancer of around 6 percent.<ref>Template:Cite web</ref> As there is a small likelihood of recurrence, further screening after polyp removal is recommended.<ref name=":2" />

Endometrial polyp

Template:Main 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.<ref name="PGU">Template:Cite book</ref> They may have a large flat base (sessile) or be attached to the uterus by an elongated pedicle (pedunculated).<ref name="PGU" /><ref name="Mayo"> Template:Cite web</ref> Pedunculated polyps are more common than sessile ones.<ref name="SDS">Template:Cite book</ref> They range in size from a few millimeters to several centimeters.<ref name="Mayo" /> If pedunculated, they can protrude through the cervix into the vagina.<ref name="PGU" /><ref name="Merck">Template:Cite web</ref> Small blood vessels may be present in polyps, particularly large ones.<ref name="PGU" />

Cervical polyp

Template:Main A cervical polyp is a common benign polyp or tumor on the surface of the cervical canal.<ref name="PAP">Template:Cite book</ref> They can cause irregular menstrual bleeding or increased pain but often show no symptoms.<ref name="Bates1997">Template:Cite book</ref>

Nasal polyps

Template:Main Nasal polyps are polypoidal masses arising mainly from the mucous membranes of the nose and paranasal sinuses. They are overgrowths of the mucosa that frequently accompany allergic rhinitis. They can be caused by inflammation and chronic sinusitis. Small nasal polyps may cause no symptoms, but larger nasal polyps can cause nasal congestion, headaches or rhinorrhea, along with other symptoms.<ref>Template:Cite web</ref><ref>Template:Cite web</ref><ref>Template:Cite web</ref>

Laryngeal polyps

Polyps on the vocal folds can take on many different forms, and can sometimes result from vocal abuse, although this is not always the cause. They can occur on one or both vocal folds, and appear as swelling, a bump (similar to a nodule), a stalk-like growth, or a blister-like lesion. Most polyps are larger than nodules, which are more similar to callouses on the vocal folds. Polyps and nodules can exhibit similar symptoms including hoarseness or breathiness, "rough" or "scratchy" voice, harshness in vocal quality, shooting pain from ear to ear, sensation of having "a lump in the back of the throat", neck pain, decreased pitch range in the voice, and vocal and bodily fatigue.<ref>Template:Cite web</ref><ref>Template:Cite journal</ref><ref>Template:Cite web</ref>

If an individual experiences symptoms for more than 2 to 3 weeks, they should see a physician. For a diagnosis, a thorough evaluation of the voice should include a physical examination, preferably by an otolaryngologist (ear, nose, and throat doctor) who specializes in voice, a voice evaluation with a speech-language pathologist (SLP), a neurological examination (in certain cases) The qualities of the voice that will be evaluated include quality, pitch, loudness, and ability to sustain voicing. In some cases, an instrumental examination may be performed with an endoscope into the mouth or nose; this gives a clear look at the vocal folds and larynx in general. In addition to this, a stroboscope (flashing light) may be used to observe the movement of the vocal folds during speech.<ref>Template:Cite journal</ref>

Polyps may be treated with medical, surgical, or behavioral intervention. Surgical intervention involves removing the polyp from the vocal fold. This approach is only used when the growth(s) are very large or have existed for an extended amount of time. In children, surgical intervention is rare. Existing medical problems may be treated in an effort to reduce the strain and negative impact on the vocal cords. This could include treatment for gastrointestinal reflux disease, allergies, and thyroid problems. Intervention to stop smoking and reduce stress may also be needed. Most people receive behavioral intervention, or vocal therapy, from an SLP. This might involve teaching good vocal hygiene, and reducing or stopping vocal abuse behaviors. Direct voice treatments may be used to alter pitch, loudness, or breathe support to promote good voicing.<ref>Template:Cite journal</ref><ref>Template:Cite web</ref>

Etymology

The name is of ancient origin, in use in English from about 1400 for a nasal polyp, from Latin Template:Lang through Greek.<ref>Template:Cite OED</ref> The animal of similar appearance called polyp is attested from 1742, although the word was earlier used for an octopus.<ref>Template:Cite web</ref>

External links

• National Institutes of Health polyp website
• Thorough review of polyposis syndromes by Dr. Ali Nawaz Khan with CME available
• "How I Do It" – Removing large or sessile colonic polyps. Dr. Brian Saunders MD FRCP; St. Mark's Academic Institute; Harrow, Middlesex, UK. Retrieved April 9, 2008.
• FAP Patient Information Sheet