Papillary tumor of the pineal region.

ABSTRACT

Primary pineal gland malignancies are uncommon and seldom have papillary architecture. We report a case of a 22-year-old male patient who presented with progressive headache, horizontal nystagmus and worsening diplopia. MRI of the brain showed a lesion in the pineal region. The patient was taken for resection of the lesion which was classified as papillary tumor of pineal region (PTPR). Histologically, the neoplasm was cellular, characterized by eosinophilic cells with indistinct borders, large pleomorphic nuclei, numerous apoptotic figures without necrosis or microvascular proliferation. Prominent perivascular pseudorosettes were seen. Diffuse immunoreactivity for cytokeratin 8-18 was noted. Synaptophysin antibody showed membranous and cytoplasmic positivity. Weak staining for GFAP, vimentin, S-100 protein, and neuron specific enolase (NSE) were observed only focally. This is a case report of this rare pineal region neoplasm which only recently has been described as a histopathologic entity. Although the clinicopathological characteristics of this tumor are not entirely understood, a brief review of the literature as well as our contribution suggest an indolent neoplasm with a tendency for local recurrence. Histologically, PTPR demonstrates a unique assortment of epithelial, ependymal, and neuroendocrine features. The differential diagnosis of papillary neoplasms of the pineal region is reviewed.