In premenopausal women, elevated prolactin can lead to reduction or loss of menstrual periods and/or breast milk production (galactorrhea). With stalk effect, prolactin levels are usually only slightly elevated, as opposed to prolactinomas in which the prolactin level is usually very high. Diabetes insipidus occurs due to the absence of a posterior pituitary hormone called antidiuretic hormone. Symptoms include:
Excessive thirst
Excessive urination
Adrenal insufficiency occurs because of a reduction in ACTH production, a reduction in cortisol. In severe cases, it can be fatal. Symptoms include:
Fatigue
Low blood pressure
Electrolyte abnormalities

Mechanisms
Craniopharyngioma is a rare, usually suprasellar neoplasm, which may be cystic, that develops from nests of epithelium derived from Rathkes pouch. Rathkes pouch is an embryonic precursor of the anterior pituitary.Craniopharyngiomas are typically very slow-growing tumors. They arise from the cells along the pituitary stalk, specifically from nests of odontogenic (tooth-forming) epithelium within the suprasellar/diencephalic region, so contain deposits of calcium that are evident on an X-ray. Diagnosis
Imaging scans for craniopharyngioma
A physician can conduct a few scans and tests to diagnose a person with craniopharyngioma. High-resolution magnetic resonance imaging (MRI) is valuable because it allows the neuroradiologist to view the tumor from different angles.In some cases, a powerful 3T (Tesla) MRI scanner can help define the location of critical brain structures affected by the tumor. 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.
Malignant craniopharyngiomas can occur at any age, are slightly more common in females, and are usually of the adamantinomatous type.The malignant transformations can take years to occur (although one in five of the diagnosed cases were de novo transformations), hence the need for lengthier follow-up in patients diagnosed with the more common benign forms.No link has been found between malignancy and initial chemoradiotherapy treatment, and the overall survival rate was very poor with median survival being 6 months after diagnosis of malignancy. Prevention
Although the causes of craniopharyngioma are unknown, it can occur in both children and adults, with a peak in incidence at 9 to 14 years of age. About 120 cases are diagnosed each year in the United States in patients under the age of 19. More than 50% of all patients with craniopharyngioma are under the age of 18 years. No clear association of the tumor exists with a particular gender or race. Craniopharyngiomas do not appear to "run in families" or to be directly inherited from the parents. Treatment
Treatment generally consists of subfrontal or transsphenoidal excision. Endoscopic surgery through the nose often performed by a joint team of neurosurgeons and ENT, is increasingly being considered as an alternative to transcranial surgery done by making an opening in the skull. 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.Additional radiotherapy is also used if total removal is not possible.