Although the causes of craniopharyngioma is unknown, it can occur in both children and adults, with a peak in incidence at 9 to 14 years of age. There are approximately 120 cases diagnosed each year in the United States in patients under the age of 19 years old. In fact, more than 50% of all patients with craniopharyngioma are under the age of 18 years. There is no clear association of the tumor with a particular gender or race. It is not really known what causes craniopharyngiomas, but they do not appear to "run in families" or to be directly inherited from the parents.

According to a Dutch source juvenile pilocytic astrocytoma occurs at a rate of 2 in 100,000 people. Most affected are children ages 5–14 years. According to the National Cancer Institute more than 80% of astrocytomas located in the cerebellum are low grade (pilocytic grade I) and often cystic; most of the remainder are diffuse grade II astrocytomas.

Tumors of the optic pathway account for 3.6-6% of pediatric brain tumors, 60% of which are juvenile pilocytic astrocytomas. Astrocytomas account for 50% of pediatric primary central nervous system tumors. About 80-85% of cerebellar astrocytomas are juvenile pilocytic astrocytomas.

Recent genetic studies of pilocytic astrocytomas show that some sporadic cases have gain in chromosome 7q34 involving the BRAF locus.

Craniopharyngiomas are generally benign but are known to recur after resection. Recent research has demonstrated a malignant (but rare) tendency of craniopharyngiomas. These malignant craniopharyngiomas are very rare, but are associated with poor prognosis.

While there is a wide age range at clinical presentation (12–85 years), most patients come to clinical attention at 55 years (mean). There is no gender difference.

Papillary tumors of pineal region are extremely rare, constituting 0.4-1% of all central nervous system tumors. These tumors most commonly occur in adults with the mean age being 31.5. There have been cases reported for people between the ages 5 to 66 years. There is a slight predominance of females who have these tumors.

Grade I pilocytic astrocytoma and cerebellar gliomas are not associated with recurrence after complete resection. Grade II astrocytomas and cerebellar gliomas are more likely to recur after surgical removal. Pilomyxoid astrocytomas may behave more aggressively than classic pilocytic astrocytoma.

After complete surgical removal, in cases of progressive/recurrent disease or when maximal surgical removal has been achieved, chemotherapy and/or radiation therapy will be considered by the medical team.

Medulloepithelioma carries a dismal prognosis with a median survival of 5 months.

The tumor is rare, affecting adults in the 4th decade most commonly. Patients are usually younger than those who present with a lipoma. There is a slight male predominance. Hibernoma are most commonly identified in the subcutaneous and muscle tissue of the head and neck region (shoulders, neck, scapular), followed by thigh, back, chest, abdomen, and arms. In rare cases hibernoma may arise in bone tissue, however it is an incidental finding.

A nervous system neoplasm is a tumor affecting the nervous system. Types include:

- Nerve sheath tumor

- Brain tumor

- Arachnoid cyst

- Optic nerve glioma

Fibrillary astrocytomas also called low grade or diffuse astrocytomas, are a group of primary slow growing brain tumors. They typically occur in adults between the ages of twenty and fifty.

Most individuals come to clinical attention during the 5th decade, although the age range is broad (20 to 80 years). There is an equal gender distribution.

Epidemiological studies are required to determine risk factors. Aside from exposure to vinyl chloride or ionizing radiation, there are no known environmental factors associated with brain tumors. Mutations and deletions of so-called tumor suppressor genes, such as P53, are thought to be the cause of some forms of brain tumor. Inherited conditions, such as Von Hippel–Lindau disease, multiple endocrine neoplasia, and neurofibromatosis type 2 carry a high risk for the development of brain tumors. People with celiac disease have a slightly increased risk of developing brain tumors.

Although studies have not shown any link between cell phone or mobile phone radiation and the occurrence of brain tumors, the World Health Organization has classified mobile phone radiation on the IARC scale into Group 2B – possibly carcinogenic. Discounting claims that current cell phone usage may cause brain cancer, modern, third-generation (3G) phones emit, on average, about 1% of the energy emitted by the GSM (2G) phones that were in use when epidemiological studies that observed a slight increase in the risk for glioma – a malignant type of brain cancer – among heavy users of wireless and cordless telephones were conducted.

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).

Hamartomas, while generally benign, can cause problems due to their location. For example, when located on the skin, especially on the face or neck, they can be very disfiguring. Cases have been reported of hamartomas the size of a small orange. They may obstruct practically any organ in the body, such as the colon, eye, etc. They are particularly likely to cause major health issues when located in the hypothalamus, kidneys, lips, or spleen. They can be removed surgically if necessary, and are not likely to recur. Prognosis will depend upon the location and size of the lesion, as well as the overall health of the patient.

Patients treated with complete surgical excision can expect an excellent long term outcome without any problems. Recurrences may be seen in tumors which are incompletely excised.

The majority of cases occur in the second and third decades, with approximately 75% of cases occurring before the age of 30 years 1,12-15. There is no recognised gender predilection. Examples have however been seen in patients up to the age of 75 years. In some series there is a male predilection 12 whilst in others no such distribution is found 2

Fibrillary astrocytomas arise from neoplastic astrocytes, a type of glial cell found in the central nervous system. They may occur anywhere in the brain, or even in the spinal cord, but are most commonly found in the cerebral hemispheres. As the alternative name of "diffuse astrocytoma" implies, the outline of the tumour is not clearly visible in scans, because the borders of the neoplasm tend to send out tiny microscopic fibrillary tentacles that spread into the surrounding brain tissue. These tentacles intermingle with healthy brain cells, making complete surgical removal difficult. However, they are low grade tumors, with a slow rate of growth, so that patients commonly survive longer than those with otherwise similar types of brain tumour, such as glioblastoma multiforme.

Surgical excision is the preferred method of treatment for benign glomus tumors.

Brain, other CNS or intracranial tumors are the ninth most common cancer in the UK (around 10,600 people were diagnosed in 2013), and it is the eighth most common cause of cancer death (around 5,200 people died in 2012).

Because of the rarity of these tumors, there is still a lot of unknown information. There are many case studies that have been reported on patients who have been diagnosed with this specific type of tumor. Most of the above information comes from the findings resulting from case studies.

Since Papillary Tumors of the Pineal Region were first described in 2003, there have been seventy cases published in the English literature. Since there is such a small number of cases that have been reported, the treatment guidelines have not been established. A larger number of cases that contain a longer clinical follow-up are needed to optimize the management of patients with this rare disease.

Even though there is a general consensus on the morphology and the immunohistochemical characteristics that is required for the diagnosis, the histological grading criteria have yet to be fully defined and its biological behavior appears to be variable. This specific type of tumor appears to have a high potential for local recurrence with a high tumor bed recurrence rate during the five years after the initial surgery. This suggests the need for a tumor bed boost radiotherapy after surgical resection.

As stated above, the specific treatment guidelines have not yet been established, however, gross total resection of the tumor has been the only clinical factor associated overall and progression-free survival. The value of radiotherapy as well as chemotherapy on disease progression will need to be investigated in future trials. With this information, it will provide important insight into long-term management and may further our understanding of the histologic features of this tumor.

The most common adverse effect is pain, which is usually associated with solitary lesions. Multiple tumors are less likely to be painful.

In one report, a patient with more than 400 glomus tumors had thrombocytopenia as a result of platelet sequestration (i.e. Kasabach-Merritt syndrome).

Malignant glomus tumors, or glomangiosarcomas, are extremely rare and usually represent a locally infiltrative malignancy. However, metastases do occur and are usually fatal.

Chondromyxoid fibroma is a type of cartilaginous tumor.

Most cases are characterised by GRM1 gene fusion or promoter swapping. It can be associated with a translocation at t(1;5)(p13;p13).

A chondromyxoid fibroma (CMF) is an extremely rare benign cartilaginous neoplasm which accounts for < 1% bone tumours.

Medulloepithelioma most commonly affect children between 6 months and 5 years; rarely, this tumour may occur congenitally or beyond this age range. Incidence is equal in males and females.

Treatment consists of wide resection or amputation. Metastases are rare at presentation but may occur in up to 30% of patients during the disease course. Prognosis is excellent, with overall survival of 85% at 10 years, but is lower when wide surgical margins cannot be obtained. This tumor is insensitive to radiation so chemotherapy is not typically used unless the cancer has metastasized to the lungs or other organs.

Ceruminous adenocarcinoma is a malignant neoplasm derived from ceruminous glands of the external auditory canal. This tumor is rare, with several names used in the past. Synonyms have included cylindroma, ceruminoma, ceruminous adenocarcinoma, not otherwise specified (NOS), ceruminous adenoid cystic carcinoma (ACC), and ceruminous mucoepidermoid carcinoma.