Papillary Tumor of the Pineal Gland: Series of Four Clinical Cases.

The papillary tumor of the pineal region (PTPR) is a rare neuroepithelial tumor originating from specialized ependymocytes. It primarily affects structures within the pineal region, including the pineal gland, epithalamus, quadrigeminal cistern, and posterior wall of the third ventricle. Here, we present a series of four cases characterized by symptoms associated with obstructive hydrocephalus such as headaches, seizures, visual disturbances, gait disturbances, and Parinaud syndrome. Imaging studies revealed lesions in the pineal region, prompting surgical intervention. Histopathological examination, including biopsy and intraoperative analysis, confirmed the diagnosis of PTPR. Despite advancements, the etiology and pathogenesis of PTPR remain incompletely understood, warranting further research to refine management strategies.

Teratoma With Malignant Ectomesenchymoma in the Pineal Region: A Case Report.

Tumors involving the pineal gland include germinomas, non-germinomatous, and parenchymal tumors. Sometimes these tumors can be differentiated into rhabdomyosarcoma, which is an aggressive and rapidly recurring sarcoma but is a rare event. We present the case of a 23-year-old male, with an eight-year-long history of a non-treated brain tumor compatible with a teratoma. Chemotherapy and radiotherapy were offered, and two years later, malignant transformation to astrocytoma, rhabdomyosarcoma, neural cell carcinoma, ganglioglioma, and low-grade chondrosarcoma was noted. Immunohistochemistry was valuable in differentiating these entities that confirmed the diagnosis. Malignant transformations may be secondary to the normal transformation of multipotent embryonic cells into more developed tissues after radiotherapy of teratoma and malignant ectomesenchymoma transformation.

Case Report of a Hemangioblastoma With Large Blood Vessels and Rare Vascular Anomalies: Is It Fibromuscular Dysplasia or Arteriovenous Malformation Association?

Hemangioblastoma is considered a benign neoplasm characterized by abnormal vasculature and stromal cells; several pathophysiological mechanisms have been proposed, such as genetic predisposition, hormonal factors, and arterial wall ischemia. Fibromuscular dysplasia is characterized by hyperplasia or thinning of the smooth muscle, elastic fibre destruction, fibrous tissue proliferation, and arterial wall disorganization. We present a cerebellar hemangioblastoma case not associated with Von Hippel Lindau syndrome. Histologically we evidenced big vessels with anomalies of the vascular walls corresponding to fibromuscular dysplasia, and those changes have not been described in these types of tumors. In this light, rare findings could be called vascular malformations or degenerative vascular changes, fibromuscular dysplasia or vascular anomalies. Arterio-venous malformation and hemangioblastoma pathology are rarely presented together. Notwithstanding, we could say that it is a stromal stem cell tumor in a varied stage of differentiation.