title: Pineocytoma and pineal parenchymal tumors of intermediate differentiation presenting cytologic pleomorphism: a multicenter study.
abstract: Cytologic pleomorphism has been described in a limited number of benign pineal tumors, namely pineocytoma (PC) and pineal parenchymal tumors (PPTs) of intermediate differentiation (PPTID). We examined the clinicopathologic features in a retrospective series of 14 cases (seven females and seven males aged from 10 to 65 years) of pleomorphic PPT. Seven cases were PC, with no mitoses and with areas of tumoral cells forming large pineocytomatous rosettes and other areas with giant cells containing hyperchromatic nuclei. The other seven were PPTID, presenting few mitoses (< or =2), a Ki67 proliferation index between 3% and 7%, and predominantly composed of small neoplastic cells and scattered giant cells, sometimes multinucleated. In the 14 tumors, the proportion of pleomorphic areas was variable. Most tumoral cells showed extensive neuronal differentiation with strong expression of neuron-specific enolase, synaptophysin and neurofilaments. Some of the neoplastic cells expressed S100 protein. The follow-up period ranged from 1.2 to 13 years and only one PC and one PPTID progressed after stereotactic biopsy or incomplete resection. The lack of invasiveness and the low proliferation index of these tumors suggest a benign clinical course despite the marked pleomorphism, the latter of which can lead to upgrading.
authors: INSERM, U842, Lyon; Université de Lyon, Lyon 1, Faculté de Médecine Laennec, UMRS842, Lyon, France. montange@lyon.inserm.fr
authors: Michelle
authors: M
authors: Fèvre-Montange
authors: Alexandru
authors: A
authors: Szathmari
authors: Jacques
authors: J
authors: Champier
authors: Karima
authors: K
authors: Mokhtari
authors: Fabrice
authors: F
authors: Chrétien
authors: Alix
authors: A
authors: Coulon
authors: Dominique
authors: D
authors: Figarella-Branger
authors: Marc
authors: M
authors: Polivka
authors: Pascale
authors: P
authors: Varlet
authors: Emmanuelle
authors: E
authors: Uro-Coste
authors: François
authors: F
authors: Fauchon
authors: Anne
authors: A
authors: Jouvet
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000378:metabolism / Q000473:pathology*; D002648:Child; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010870:Pineal Gland / Q000378:metabolism / Q000473:pathology*; D010871:Pinealoma / Q000378:metabolism / Q000473:pathology*