The pineal gland is situated below an area which divides the two cerebral hemispheres. Tumours in this part of the brain are extremely rare. The commonest pineal tumours are germinomas, others include teratomas, pineocytomas and pineoblastomas. They can occur in most parts of the brain or spinal cord and usually grow very slowly. Most meningiomas are benign and do not spread from their original site.
Malignant meningiomas are very rare.
Acoustic neuromas are benign tumours that develop in the acoustic or auditory nerve which controls hearing. The nerve contains cells called schwann cells from which the tumour arises, which is why it is also known as a schwannoma. Acoustic neuromas are usually found only in adults and can be connected with the genetic disease called neurofibromatosis type II . This is a rare type of tumour that develops from blood vessel cells. Haemangioblastomas are almost always benign and grow very slowly.