This is a very rare neoplasm accounting for approximately 0.0003% of all tumors and about 2.5% of all external ear neoplasms. There is a wide age range at initial presentation, although the mean age is about 50 years of age. Females are affected slightly more often (1.5:1).

Taste disturbance and mouth dryness are frequent for a few weeks following surgery. In a few patients this disturbance is longer or permanent.

The cause of acoustic neuromas is usually unknown; however there is a growing body of evidence that sporadic defects in tumor suppressor genes may give rise to these tumors in some individuals. In particular, loss or mutation of a tumor suppressor gene on the long arm of chromosome 22 is strongly associated with vestibular schwannomas. Other studies have hinted at exposure to loud noise on a consistent basis. One study has shown a relationship between acoustic neuromas and prior exposure to head and neck radiation, and a concomitant history of having had a parathyroid adenoma (tumor found in proximity to the thyroid gland controlling calcium metabolism). There are even controversies on hand held cellular phones. Whether or not the radiofrequency radiation has anything to do with acoustic neuroma formation, remains to be seen. To date, no environmental factor (such as cell phones or diet) has been scientifically proven to cause these tumors. The Acoustic Neuroma Association (ANA) does recommend that frequent cellular phone users use a hands free device to enable separation of the device from the head.

Although there is an inheritable condition called Neurofibromatosis Type 2 (NF2) which can lead to acoustic neuroma formation in some people, most acoustic neuromas occur spontaneously without any evidence of family history (95%). NF2 occurs with a frequency of 1 in 30,000 to 1 in 50,000 births. The hallmark of this disorder is bilateral acoustic neuromas (an acoustic neuroma on both sides) usually developing in late childhood or early adulthood, frequently associated with other brain and spinal chord tumors.

Wide, radical, complete surgical excision is the treatment of choice, with free surgical margins to achieve the best outcome and lowest chance of recurrence. Radiation is only used for palliation. In general, there is a good prognosis, although approximately 50% of patients die from disease within 3–10 years of presentation.

In most cases, the cause of acoustic neuromas is unknown. The only statistically significant risk factor for developing an acoustic neuroma is having a rare genetic condition called neurofibromatosis type 2 (NF2). There are no confirmed environmental risk factors for acoustic neuroma. There are conflicting studies on the association between acoustic neuromas and cellular phone use and repeated exposure to loud noise. In 2011, an arm of the World Health Organization released a statement listing cell phone use as a low grade cancer risk. The Acoustic Neuroma Association recommends that cell phone users use a hands-free device.

Meningiomas are significantly more common in women than in men; they are most common in middle-aged women. Two predisposing factors associated with meningiomas for which at least some evidence exists are exposure to ionizing radiation (cancer treatment of brain tumors) and hormone replacement therapy.

Familial and genetic factors are identified in 5-15% of childhood cancer cases. In <5-10% of cases, there are known environmental exposures and exogenous factors, such as prenatal exposure to tobacco, X-rays, or certain medications. For the remaining 75-90% of cases, however, the individual causes remain unknown. In most cases, as in carcinogenesis in general, the cancers are assumed to involve multiple risk factors and variables.

Aspects that make the risk factors of childhood cancer different from those seen in adult cancers include:

- Different, and sometimes unique, exposures to environmental hazards. Children must often rely on adults to protect them from toxic environmental agents.

- Immature physiological systems to clear or metabolize environmental substances

- The growth and development of children in phases known as "developmental windows" result in certain "critical windows of vulnerability".

Also, a longer life expectancy in children avails for a longer time to manifest cancer processes with long latency periods, increasing the risk of developing some cancer types later in life.

There are preventable causes of childhood malignancy, such as delivery overuse and misuse of ionizing radiation through computed tomography scans when the test is not indicated or when adult protocols are used.

Adult survivors of childhood cancer have some physical, psychological, and social difficulties.

Premature heart disease is a major long-term complication in adult survivors of childhood cancer. Adult survivors are eight times more likely to die of heart disease than other people, and more than half of children treated for cancer develop some type of cardiac abnormality, although this may be asymptomatic or too mild to qualify for a clinical diagnosis of heart disease.

The overall complication rate following surgery is around 20%; cerebrospinal fluid leak is the most common.

Prognosis is highly variable and dependent upon a multitude of factors. Reoccurrence does occur. Treatment is determined on a case-by-case basis.

A urogenital neoplasm is a tumor of the urogenital system.

Types include:

- Cancer of the breast and female genital organs: (Breast cancer, Vulvar cancer, Vaginal cancer, Cervical cancer, Uterine cancer, Endometrial cancer, Ovarian cancer)

- Cancer of the male genital organs (Carcinoma of the penis, Prostate cancer, Testicular cancer)

- Cancer of the urinary organs (Renal cell carcinoma, Bladder cancer)

The clinical spectrum of the condition is broad. In other words, people with NF II may develop a wide range of distinct problems.

1. Acoustic nerve: 90% of the patients show bilateral acoustic schwannomas on magnetic resonance imaging (MRI).

2. Other cranial nerves and meninges: About 50% of patients develop tumours in other cranial nerves or meningiomas.

3. Spinal cord: About 50% of the patients develop spinal lesions. Only 40% of the spinal lesions are symptomatic. The spinal tumours in NF II are separated in two groups. Intramedullary lesions are located within the spinal tissue and usually belong to the so-called spinal astrocytomas or ependymomas. The extramedullary lesions are located within the small space between the surface of the spinal cord and the bony wall of the spinal canal. These tumours belong to the schwannomas and meningiomas.

4. Skin: If children show neurofibromas, a diagnostic procedure should be performed to decide which form of neurofibromatosis causes the alterations.

5. Eyes: Studies on patients with NF II show that more than 90% of the affected persons suffer eye lesions. The most common alteration in NF II is the juvenile subcapsular cataract (opacity of the lens) in young people.

"Presenting symptoms" (initial concern that brings a patient to a doctor) of a lesion of the nervus vestibulocochlearis due to a tumour in the region of the cerebello-pontine angle are the following: hearing loss (98%), tinnitus (70%), dysequilibrium (67%), headache (32%), facial numbness and weakness (29% and 10% respectively).

"Clinical signs" (alterations that are not regarded by the patient and that can be detected by the doctor in a clinical examination) of the lesion in discussion are: abnormal corneal reflex (33%), nystagmus (26%), facial hypesthesia (26%).

Evaluation (study of the patient with technical methods) shows the enlargement of the porus acousticus internus in the CT scan, enhancing tumours in the region of the cerebello-pontine angle in gadolinium-enhanced MRI scans, hearing loss in audiometric studies and perhaps pathological findings in electronystagmography. Some times there are elevated levels of protein in liquor study.

In NF II, acoustic neuromas usually affect young people, whereas in sporadic forms of acoustic neuromas, the appearance of the tumour is limited to the elderly.

There are two forms of the NF II:

- The "Wishart-Phenotype" is characterized by multiple cerebral and spinal lesions in patients younger than 20 years and with rapid progression of the tumours.

- Patients that develop single central tumours with slow progression after age of 20 are thought to have the "Feiling-Gardner-Phenotype".

Because hearing loss in those with NF-2 almost always occurs after acquisition of verbal language skills, patients do not always integrate well into the Deaf culture and are more likely to resort to auditory assistive technology.

The most sophisticated of these devices is the cochlear implant, which can sometimes restore a high level of auditory function even when natural hearing is totally lost. However, the amount of destruction to the cochlear nerve caused by the typical NF2 schwannoma often precludes the use of such an implant. In these cases, an auditory brainstem implant (ABI) can restore a primitive level of hearing, which, when supplemented by lip reading, can restore a functional understanding of spoken language.

While there is no cure, most people with tinnitus get used to it over time; for a minority, it remains a significant problem.

Ototoxic effects are also seen with quinine, pesticides, solvents, asphyxiants and heavy metals such as mercury and lead. When combining multiple ototoxins, the risk of hearing loss becomes greater.

Ototoxic chemicals in the environment (from contaminated air or water) or in the workplace interact with mechanical stresses on the hair cells of the cochlea in different ways. For organic solvents such as toluene, styrene or xylene, the combined exposure with noise increases the risk of hearing loss in a synergistic manner. Carbon monoxide, has been shown to increase the severity of the hearing loss from noise. Given the potential for enhanced risk of hearing loss, exposures and contact with products such as paint thinners, degreasers, white spirits, exhaust, should be kept to a minimum. Noise exposures should be kept below 85 decibels, and the chemical exposures should be below the recommended exposure limits given by regulatory agencies.

Drug exposures mixed with noise potentially lead to increased risk of ototoxic hearing loss. Noise exposure combined with the chemotherapeutic cisplatin puts individuals at increased risk of ototoxic hearing loss. Noise at 85 dB SPL or above added to the amount of hair cell death in the high frequency region of the cochlea In chinchillas. The American Academy of Audiology includes in their position statement that exposure to noise at the same time as aminoglycosides may exacerbate ototoxicity. The American Academy of Audiology recommends people being treated with ototoxic chemotherapeutics avoid excessive noise levels during treatment and for several months following cessation of treatment. Opiates in combination with excessive noise levels may also have an additive affect on ototoxic hearing loss.

Previous noise exposure has not been found to potentiate ototoxic hearing loss.

NF1 occurs in 1 in 3000 individuals and is equally prevalent among men and women. It is among the most common inherited nervous system disorders. Affected individuals have a 10- to 15-year reduction in life expectancy compared to the average person.

In most cases, symptoms of NF1 are mild, and individuals live normal and productive lives. In some cases, however, NF1 can be severely debilitating and may cause cosmetic and psychological issues. The course of NF2 varies greatly among individuals. In some cases of NF2, the damage to nearby vital structures, such as other cranial nerves and the brain stem, can be life-threatening. Most individuals with schwannomatosis have significant pain. In some extreme cases the pain will be severe and disabling.

Invasive urothelial carcinoma is a type of transitional cell carcinoma or TCC and urothelial cell carcinoma or UCC. It is a type of cancer that develops in the urinary system: the kidney, urinary bladder, and accessory organs. It is the most common type of bladder cancer and cancer of the ureter, urethra, renal pelvis, the ureters, the bladder, and parts of the urethra and urachus.. It originates from tissue lining the inner surface of these hollow organs - transitional epithelium. The invading tumors can extend from the kidney collecting system to the bladder.

Carcinoma (from the Greek "karkinos", or "crab", and "-oma", "growth") is a type of cancer. A carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that generally arises from cells originating in the endodermal or ectodermal germ layer during embryogenesis.

Tinnitus is commonly thought of as a symptom of adulthood, and is often overlooked in children. Children with hearing loss have a high incidence of tinnitus, even though they do not express the condition or its effect on their lives. Children do not generally report tinnitus spontaneously and their complaints may not be taken seriously. Among those children who do complain of tinnitus, there is an increased likelihood of associated otological or neurological pathology such as migraine, juvenile Meniere’s disease or chronic suppurative otitis media. Its reported prevalence varies from 12% to 36% in children with normal hearing thresholds and up to 66% in children with a hearing loss and approximately 310% of children have been reported to be troubled by tinnitus.

About 22 million workers are exposed to hazardous noise, with additional millions exposed to solvents and metals that could put them at increased risk for hearing loss. Occupational hearing loss is one of the most common occupational diseases. 49% of male miners have hearing loss by the age of 50. By the age of 60, this number goes up to 70%. Construction workers also suffer an elevated risk. A screening program focused on construction workers employed at US Department of Energy facilities found 58% with significant abnormal hearing loss due to noise exposures at work. Occupational hearing loss is present in up to 33% of workers overall. Occupational exposure to noise causes 16% of adult disabling hearing loss worldwide.

The following is a list of occupations that are most susceptible to hearing loss:

- Agriculture

- Mining

- Construction

- Manufacturing

- Utilities

- Transportation

- Military

- Musicians

- Orchestra conductors

At high doses, quinine, aspirin and other salicylates may also cause high-pitch tinnitus and hearing loss in both ears, typically reversible upon discontinuation of the drug.

The erectile dysfunction medications Viagra, Levitra, and Cialis have also been reported to cause hearing loss.

The World Health Organization estimates that nearly 360 million people have moderate to profound hearing loss from all causes. Rates of hearing loss has traditionally been attributed to occupational or firearm-related exposure, as well as recreational exposure. The World Health Organization estimated in 2015 that 1.1 billion young people are at risk for hearing loss caused by unsafe listening practices. The over-exposure to excessive loud noise is partially attributed to recreational exposure, such as the use of personal audio devices with music at high volumes for long durations, or social settings such as bars, entertainment and sporting events.

Approximately 24% adults age 20-69 in the United States has an audiometric notch, suggesting high levels of noise exposure as of 2011. This data identified differences in NIHL based on age, gender, race/ethnicity, and whether or not a person is exposed to noise at work. Among people aged 20–29, 19.2% had an audiometric notch, compared to 27.3% of people aged 50–59. Males in general had a notch more often than females, regardless of occupational noise exposure, for both unilateral and bilateral audiometric notches.

Occupational noise exposure is a risk factor for noise induced hearing loss. One study examined hearing test results obtained between 2000-2008 for workers ages 18–65 who had a higher occupational noise exposure than the average worker. Of the sample taken, 18% of the workers had hearing loss. Of the occupations considered, the Mining industry had the highest prevalence and risk of hearing loss, at approximately 27%. Other industries with a higher prevalence and risk included Construction (23.48%) and Manufacturing, especially Wood Product and Non-metallic Mineral Product (19.89%), Apparel (20.18%), and Machinery (21.51%).

Cancer of the stomach, also called gastric cancer, is the fourth-most-common type of cancer and the second-highest cause of cancer death globally. Eastern Asia (China, Japan, Korea, Mongolia) is a high-risk area for gastric cancer, and North America, Australia, New Zealand and western and northern Africa are areas with low risk. The most common type of gastric cancer is adenocarcinoma, which causes about 750,000 deaths each year. Important factors that may contribute to the development of gastric cancer include diet, smoking and alcohol consumption, genetic aspects (including a number of heritable syndromes) and infections (for example, "Helicobacter pylori" or Epstein-Barr virus) and pernicious anemia. Chemotherapy improves survival compared to best supportive care, however the optimal regimen is unclear.

Although metastasis is widely accepted to be the result of the tumor cells migration, there is a hypothesis saying that some metastases are the result of inflammatory processes by abnormal immune cells. The existence of metastatic cancers in the absence of primary tumors also suggests that metastasis is not always caused by malignant cells that leave primary tumors.

Digestive system neoplasms are tumors which affect the digestive system. Types include:

- esophageal cancer

- gastric cancer

- small intestinal cancer

- colorectal cancer

- anal cancer

A stroke (either ischemic or hemorrhagic) involving the posterior fossa is a cause of central vertigo. Risk factors for a stroke as a cause of vertigo include increasing age and known vascular risk factors. Presentation may more often involve headache or neck pain, additionally, those who have had multiple episodes of dizziness in the months leading up to presentation are suggestive of stroke with prodromal TIAs. The HINTS exam as well as imaging studies of the brain (CT, CT angiogram, and/or MRI) are helpful in diagnosis of posterior fossa stroke.