Pineal region metastasis with intraventricular seeding: A case report and literature review.

Introduction: Tumors of the pineal region are rare, and metastatic carcinoma occurring in the pineal region is extremely rare. No previous reports have described pineal region metastasis with intraventricular seeding.
Patient Concerns: We report a case of a 51-year-old woman presented with a 1-week history of severe headache, nausea, and vomiting. Imaging examination revealed 2 lesions in the pineal region and the right lateral ventricle.
Diagnosis: Pinealocytoma or germinoma was considered as the preoperative diagnosis. The postoperative pathological diagnosis was small cell neuroendocrine carcinoma. After bronchoscopic biopsy, small cell lung cancer was confirmed.
Interventions: A right frontal craniotomy and a translateral ventricle approach were performed to remove 2 lesions completely. And regular radiotherapy and chemotherapy were initiated after surgery.
Outcomes: The patient was discharged from the hospital 2 weeks after operation and went to another cancer hospital for bronchoscopic biopsy, radiotherapy, and chemotherapy. Finally, the patient died 2 years after surgical treatment.
Conclusion: Metastatic tumors of the pineal region are very rare. For patients with pineal lesions, a diagnosis of a metastatic tumor should be considered. Retrograde cerebrospinal fluid circulation might be the reason for a secondary metastasis.