This is an uncommon lesion, usually affecting young patients (mean age, 30 years), with a male to female ratio of 2:1. The middle ear is involved, although it may extend to the external auditory canal if there is tympanic membrane perforation.

Nasal glial heterotopia is rare, while an encephalocele is uncommon. NGH usually presents in infancy, while encephalocele may present in older children and adults. It is seen in both genders equally.

Inflammatory fibroid polyp, abbreviated IFP, is a benign abnormal growth of tissue projecting into the lumen of the gastrointestinal tract.

99% of cervical polyps will remain benign and 1% will at some point show neoplastic change. Cervical polyps are unlikely to regrow.

The exact cause of nasal polyps is unclear. They are, however, commonly associated with conditions that cause long term inflammation of the sinuses. This includes chronic rhinosinusitis, asthma, aspirin sensitivity, and cystic fibrosis.

Various additional diseases associated with polyp formation include:

Chronic rhinosinusitis is a common medical condition characterized by symptoms of sinus inflammation lasting at least 12 weeks. The cause is unknown and the role of microorganisms remains unclear. It can be classified as either with or without nasal polyposis.

Cystic fibrosis (CF) is the most common cause of nasal polyps in children. Therefore, any child under 12 to 20 years old with nasal polyps should be tested for CF. Half of people with CF will experience extensive polyps leading to nasal obstruction and requiring aggressive management.

An otic polyp (also called aural polyp) is a benign proliferation of chronic inflammatory cells associated with granulation tissue, in response to a longstanding inflammatory process of the middle ear.

Polypoid lesions of the gallbladder affect approximately 5% of the adult population. The causes are uncertain, but there is a definite correlation with increasing age and the presence of gallstones (cholelithiasis). Most affected individuals do not have symptoms. The gallbladder polyps are detected during abdominal ultrasonography performed for other reasons.

The incidence of gallbladder polyps is higher among men than women. The overall prevalence among men of Chinese ancestry is 9.5%, higher than other ethnic types.

Although surgery is the treatment of choice, it must be preceded by imaging studies to exclude an intracranial connection. Potential complications include meningitis and a cerebrospinal fluid leak. Recurrences or more correctly persistence may be seen in up to 30% of patients if not completely excised.

Cervical polyps are most common in women who have had children and perimenopausal women. They are rare in pre-menstrual girls and uncommon in post-menopausal women.

IFPs consist of spindle cells that are concentrically arranged around blood vessels and have inflammation, especially eosinophils.

They may have leiomyoma/schwannoma-like areas with nuclear palisading.

They typically stain with CD34 and vimentin, and, generally, do not stain with CD117 and S100.

The endoscopic differential diagnosis includes other benign, pre-malignant and malignant gastrointestinal polyps.

Epidermoid cysts commonly result from implantation of epidermis into the dermis, as in trauma or surgery. They can also be caused by a blocked pore adjacent to a body piercing. They are also seen in Gardner's syndrome and Nevoid Basal Cell Carcinoma Syndrome on the head and neck. They can be infected by bacteria and form a pimple-like shape.

There are two primary types of nasal polyps: ethmoidal and antrochoanal. Ethmoidal polyps arise from the ethmoid sinuses and extend through the middle meatus into the nasal cavity. Antrochoanal polyps usually arise in the maxillary sinus and extend into the nasopharynx and represent only 4-6% of all nasal polyps. However, antrochoanal polyps are more common in children comprising one-third of all polyps in this population. Ethmoidal polyps are usually smaller and multiple while antrochoanal polyps are usually single and larger.

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. 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 by detecting and removing them.

According to the guidelines established by the American Cancer Society, individuals who reach the age of 50 should perform an occult blood test yearly. Colon polyps as they grow can sometimes cause bleeding within the intestine, which can be detected with the help of this test. Also, persons in their 50s are recommended to have flexible sigmoidoscopies performed once in 3 to 5 years to detect any abnormal growth which could be an adenomatous polyp. If adenomatous polyps are detected during this procedure, it is most likely that the patient will have to undergo a colonoscopy. Medical societies recommend colonoscopies every ten years starting at age 50 as a necessary screening practice for colon cancer. 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, there are several methods of removal including using a snare or a heating device. Colonoscopies are preferred over sigmoidoscopies because they allow the examination of the entire colon; a very important aspect, considering that more than half of the colonic polyps occur in the upper colon, which is not reached during sigmoidoscopies.

It has been statistically demonstrated that screening programs are effective in reducing the number of deaths caused by colon cancer due to adenomatous polyps. While there are risks of complications associated with colonoscopies, those risks are extremely low at approximately 0.35 percent. For comparison, the lifetime risk of developing colon cancer is around 6 percent. As there is a small likelihood of recurrence, surveillance after polyp removal is recommended.

Most juvenile polyps are benign, however, malignancy can occur. The cumulative lifetime risk of colorectal cancer is 39% in patients with juvenile polyposis syndrome.

An epidermoid cyst is a benign cyst usually found on the skin. The cyst develops out of ectodermal tissue. Histologically, it is made of a thin layer of squamous epithelium.

A polyp is an abnormal growth of tissue 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, ear, sinus(es), urinary bladder, and uterus. They may also occur elsewhere in the body where mucous membranes exist like the cervix, vocal folds, and small intestine. Some polyps are tumors (neoplasms) and others are nonneoplastic (for example, hyperplastic or dysplastic). The neoplastic ones are generally benign, although some can be premalignant and/or concurrent with a malignancy.

Diet and lifestyle are believed to play a large role in whether colorectal polyps form. Studies show there to be a protective link between consumption of cooked green vegetables, brown rice, legumes, and dried fruit and decreased incidence of colorectal polyps.

Gallbladder polyps are growths or lesions resembling growths (polypoid lesions) in the wall of the gallbladder. True polyps are abnormal accumulations of mucous membrane tissue that would normally be shed by the body. The main types of polypoid growths of the gallbladder include cholesterol polyp/cholesterosis, cholesterosis with fibrous dysplasia of gallbladder, adenomyomatosis, hyperplastic cholecystosis, and adenocarcinoma.

Cholesteatoma is a destructive and expanding growth consisting of keratinizing squamous epithelium in the middle ear and/or mastoid process. Although cholesteatomas are not classified as either tumors or cancers, they can still cause significant problems because of their erosive and expansile properties resulting in the destruction of the bones of the middle ear (ossicles), as well as their possible spread through the base of the skull into the brain. They are also often infected and can result in chronically draining ears.

No definitive cause of endometrial polyps is known, but they appear to be affected by hormone levels and grow in response to circulating estrogen. Risk factors include obesity, high blood pressure and a history of cervical polyps. Taking tamoxifen or hormone replacement therapy can also increase the risk of uterine polyps. The use of an intrauterine system containing levonorgestrel in women taking tamoxifen may reduce the incidence of polyps.

Juvenile Polyposis Syndrome can occur sporadically in families or be inherited in an autosomal dominant manner.

Two genes associated with Juvenile Polyposis Syndrome are BMPR1A and SMAD4. Gene testing may be useful when trying to ascertain which non-symptomatic family members may be at risk of developing polyps, however having a known familial mutation would be unlikely to change the course of treatment. A known mutation may also be of use for affected individuals when they decide to start a family as it allows them reproductive choices.

While mutations in the gene PTEN were also thought to have caused Juvenile Polyposis Syndrome, it is now thought that mutations in this gene cause a similar clinical picture to Juvenile Polyposis Syndrome but are actually affected with Cowden syndrome or other phenotypes of the PTEN hamartoma tumor syndrome.

Complete removal of a SSA is considered curative.

Several SSAs confer a higher risk of subsequently finding colorectal cancer and warrant more frequent surveillance. The surveillance guidelines are the same as for other colonic adenomas. The surveillance interval is dependent on (1) the number of adenomas, (2) the size of the adenomas, and (3) the presence of high-grade microscopic features.

Endometrial polyps are usually benign although some may be precancerous or cancerous. About 0.5% of endometrial polyps contain adenocarcinoma cells. Polyps can increase the risk of miscarriage in women undergoing IVF treatment. If they develop near the fallopian tubes, they may lead to difficulty in becoming pregnant. Although treatments such as hysteroscopy usually cure the polyp concerned, recurrence of endometrial polyps is frequent. Untreated, small polyps may regress on their own.

Smoking is the number one cause of Reinke's edema. Other factors include gastroesophageal reflux, hypothyroidism and chronic overuse of the voice. Smoking is the only risk factor that may lead to cancer. Additionally, the combination of several risk factors increase the likelihood of an individual developing Reinke's edema. For example, an individual who smokes and also has gastric reflux would have an increased susceptibility for developing Reinke's edema over time.

Reinke's edema is commonly diagnosed in middle-aged females with a history of smoking (aged 50 years or older). Because males have lower pitched voices than females, males are less likely to observe a significant changes in the voice, and are therefore less likely to seek treatment. Females also report more physical discomfort due to Reinke's edema. The risk of Reinke's edema increases with age and also with prolonged exposure to smoking. Additionally, individuals in professions that require constant use of the voice, such as singers, teachers, and radio hosts, may be at an increased risk for developing the disease.

Because the disease is heavily linked to smoking, there is no established way to screen for Reinke's edema. Similarly, the only way to prevent Reinke's edema is to avoid smoking. By adopting a non-smoking lifestyle after being diagnosed with Reinke's edema, it is possible to stop the disease's progression, although it is not possible to reverse it. Therefore, it is critical to maintain a non-smoking lifestyle even after surgery, because the fluid can re-emerge. In fact, in many cases surgeons will not perform surgery without the guarantee that the individual will stop smoking.

These are polyps which are associated with inflammatory conditions such as Ulcerative Colitis and Crohns disease.