Endocrine Abstracts

Introduction: Tumors of the pineal region are rare, constitute 0.5% to 1% of intracranial tumors in adults in Europe and the United States. Anatomical location deeply buried under the cerebral hemispheres behind the third ventricle and the brainstem, and the variety of different histological types explain management difficulties. Cysts of the pineal gland, often calcified, may go unnoticed and be discovered during autopsy especially in the elderly, but some cysts are symptomatic and cause signs related to compression of the aqueduct of Sylvius or the tectal blade.

Observation: Patient aged 20, with no particular history, was brought by his father to the psychiatry department for behavioral disorder such as psychomotor instability with subtotal insomnia. During his stay in psychiatry, and given the negative dosage of toxicants, an organic cause was suspected justifying his transfer to our department where a brain magnetic resonance imaging revealed a simple cystic lesion of the pineal gland measuring 18.5 × 13 mm. However, there was no intracranial expansive process or hypothalamopituitary anomaly. 6-sulfatomelatonin in urine (ELISA) returned to 26.4 μg/24 hours (15.6-58.1), which is correct; plasma beta hCG returned to 0.1 mIU/ml (0-1) so normal, and the alpha-fetoprotein returned to 1.01 IU/ml (00-5.8) also normal. A neurosurgical opinion is requested recommending six-monthly radiological monitoring, with possible evacuation puncture at the slightest clinical deterioration or appearance of signs of compression.

Discussion-Conclusion: Epithelial cysts of the pineal region are benign formations with fluid content, asymptomatic in most cases, developed at the expense of the pineal parenchyma. Magnetic resonance imaging most often makes the diagnosis. Some of these cysts increase in size and cause clinical decompensation by compressing the quadrigeminal plate leading to extrinsic stenosis of the aqueduct of Sylvius or by mass syndrome in the posterior fossa.