Mr Michael Powell
National Hospital, London

Mr Richard Hayward
Great Ormond Street Hospital, London

The position of the tumour within the brain determines the complexity of the condition. The simplest situation arises when the tumour lies in or below the pituitary fossa. Cases with Pituitary gland involvement are more complicated, and those where the optic nerves and the third ventricle of the brain are affected may have most problems post-surgery.

Craniopharyngiomas are one of the most difficult and challenging conditions to treat for the multi-disciplinary team. They are very rare benign (non-cancerous) tumours, with 50% occurring in children under 16 years, and the remainder occurring at any time in adult life. About 15-20 new cases arise each year in the UK, so it is difficult to get the concentration of experience and optimise treatment in any one centre. A Craniopharyngioma may be an embryological derivative, but as yet it is not known why they occur. The tumours can be solid, cystic (full of fluid), calcified, or full of debris (keratin). They are slow-growing insidious tumours that can take 2-3 years (or longer) to manifest themselves before a diagnosis is made, and are often picked up when patients experience visual problems.

Symptoms

These are mainly endocrine problems, visual changes and pressure symptoms (headache), or a combination of any or all of these. Once the pituitary gland, stalk and Hypothalamus are involved, the ability to control functions essential for life and well-being are altered, as the hypothalamus controls body metabolism and synchronisation with the outside world. The hypothalamus also controls thirst, eating, weight, body temperature, aggression, memory, concentration and IQ.

Children with hypothalamic damage get hyperphagia (fight and steal for food), altered sleep patterns, learning and behavioural problems, and change in character. This has a devastating effect for the whole family and can ruin family life. Children can accommodate larger tumours due to their anatomy.

Diagnosis

MRI (Magnetic Resonance Imaging) is the scan of choice; CT scanning may be helpful. Visual fields should be tested.

Treatment

Prior to surgery, it is essential to test endocrine function, particularly Cortisol, Thyroxine and Prolactin, to assess which pituitary hormones are deficient. Adrenocorticotrophic Hormone (ACTH) is essential for life and would need to be replaced immediately as Hydrocortisone. Surgery is performed to prevent further pressure symptoms, i.e. visual disturbances, hydrocephalus (fluid on the brain) and to 'cure' the patient. It is a critical situation and management decisions are difficult, so patients must be referred to expert centres that can offer the whole package of care (surgery, Radiotherapy and medical follow-up with an Endocrinologist).

Transsphenoidal surgery is the first choice, but damage can occur to the anterior and posterior pituitary, arteries to the brain or nerves of the eye, as well as a possibility of Cerebrospinal fluid leakage. Transcranial surgery, through the cavity of the brain, is the most challenging surgical technique, but is necessary if the tumour lies above the pituitary gland/fossa. Damage can occur to the carotid vessels, nerves for smell, optic nerves for vision or the hypothalamus (which can dramatically change lifestyle). Exciting photodynamic surgery is being pioneered in Leeds for pituitary adenomas, but is still in the early research stages and may not have any application in craniopharyngioma. Radiotherapy may be used as a follow-up treatment.

Younger patients may be referred for radiotherapy. In adults it is thought that up to 75% of the tumours are sensitive to radiotherapy and will show signs of growth stoppage and shrinkage. As radiotherapy can continue to work for up to 10 years it is vital that all patients, young or old, have regular pituitary function tests to assess hormonal status.