<prompt> Answer this question truthfullyWhat is the explanation for the Pineocytoma and what is its natural history, possible complications, and prognosis?  <response>: <reason> If left untreated, patients with pineocytoma may progress to develop seizures, obstructive hydrocephalus, local recurrence, and CSF metastasis. Common complications of pineocytoma include: Obstructive hydrocephalus Local recurrence CSF metastasis Distant metastasis most commonly, lungPrognosis is generally excellent, and the 5-year survival rate of patients with pineocytoma is approximately 86. Pineocytoma has the most favorable prognosis among all the pineal gland tumors. Clark et al. after performing a systematic review of the literature reported that the 1- and 5-year progression free survival PFS rates for patients that underwent resection versus the biopsy group were 97 and 90, and 89 and 75 respectively. The 1- and 5-year PFS rates for the gross total resection group versus the group undergoing subtotal resection combined with radiation therapy were 100 and 94, and 100 and 84 respectively. 