In children, tumors of the pineal area account for 3–8% of all intracranial lesions. Pinealocytes, supporting cells of the pineal gland, or glial cells from the nearby midbrain or thalamus can cause neoplasms in this area, which can range from benign to mali- -gnant. Up to 53% of malignant tumour’s identified in the pinealarea are germ cell tumor’s. Malignant somatic transformation ofgerm cell tumour’s in the pineal area is uncommon and seldomdescribed. After multiple cycles of neoadjuvant treatment, a pinealyolk sac tumour with an enteric type of mucinous adenocarcinomaregrew relatively quickly.
