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, lung)
Prognosis 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.
What is the explanation for the Pineocytoma and what is its natural history, possible complications, and prognosis?
<s>[INST] Answer the question truthfully, you are a medical professional. This is the question: What is the explanation for the Pineocytoma and what is its natural history, possible complications, and prognosis? [/INST] \n 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, lung)
Prognosis 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.</s>