Craniopharyngioma

Craniopharyngioma is a type of brain tumor derived from pituitary gland embryonic tissue, that occurs most commonly in children but also in men and women in their 50s and 60s. It arises from nests of odontogenic (tooth-forming) epithelium within the suprasellar/diencephalic region and, therefore, contains deposits of calcium, which are evident on an x-ray. Histologically, craniopharyngiomas resemble adamantinomas (the most common tumors of the tooth). Patients may present with bitemporal inferior quadrantanopia leading to bitemporal hemianopia, as the tumor may compress the optic chiasm.

It has a point prevalence of approximately 2/100,000.

Craniopharyngiomas are also known as Rathke pouch tumors, hypophyseal duct tumors, or adamantinomas.

Presentation
Craniopharyngiomas are typically very slow growing tumors. They arise from the cells along the pituitary stalk. They are classified by histology as benign; however, as with many brain tumors, their treatment can be difficult, and significant morbidities are associated with both the tumor and treatment.

Craniopharyngioma is a rare, usually suprasellar neoplasm, which may be cystic, that develops from nests of epithelium derived from Rathke's pouch. Rathke's pouch is an embryonic precursor of the anterior pituitary.

Histology
The histologic pattern consists of nesting of squamous epithelium bordered by radially arranged cells. It is frequently accompanied by calcium deposition and may have a microscopic papillary architecture.

Two distinct types are recognized:
 * Adamantinomatous craniopharyngioma and,
 * Papillary craniopharyngioma.

In the adamantinomatous type, calcifications are visible on neuroimaging and are helpful in diagnosis. The papillary type rarely calcifies.

On macroscopic examination, craniopharyngiomas are cystic or partially cystic with solid areas. On light microscopy, the cysts are seen to be lined by stratified squamous epithelium. Keratin pearls may also be seen. The cysts are usually filled with a yellow, viscous fluid which is rich in cholesterol crystals. In addition to a long list of possible symptoms, the most common presentation include: headaches, growth failure, and bitemporal hemianopsia.

Prognosis
Craniopharyngiomas are generally benign but are known to recur after resection.

Treatment
Treatment generally consists of subfrontal or transsphenoidal excision. Surgery using the transsphenoidal route is often performed by a joint team of ENT and neurosurgeons. Because of the location of the craniopharyngioma near the brain and skullbase, a surgical navigation system might be used to verify the position of surgical tools during the operation. Adjuvant radiotherapy is also used if total removal is not possible. Due to the morbidities associated with damage to the pituitary and hypothalamus from surgical removal and radiation, experimental therapies using intracavitary phosphorus-32, yttrium, or bleomycin delivered via an external reservoir are frequently employed, especially in young patients. The tumor, being in the pituitary gland, can cause secondary health issues such as the following. Unstable growth hormone levels (either too little or too much, the latter causing gigantism). The immune system, thyroid levels, and testosterone levels can also be compromised from Crainopharyngioma. All of the before mentioned health issues can be treated with modern medicine.

Possible symptoms

 * Amenorrhea
 * Anorexia
 * Balance disorder
 * Dry skin
 * Fatigue
 * Fever
 * Headache (obstructive hydrocephalus)
 * Hypersomnia
 * Lethargy
 * Myxedema
 * Nausea
 * Short stature
 * Polydipsia
 * Polyuria (diabetes insipidus)
 * Vision loss (bitemporal hemianopia)
 * Vomiting
 * Weight gain