title: Relationship between focal cortical dysplasia and epilepsy-associated low-grade tumors: an immunohistochemical study.
abstract: We retrospectively analyzed 29 seizure-associated temporal lobe low-grade tumors to evaluate the utility of CD34 and bcl-2 expression in clarifying the relationship of these tumors with different classes of focal cortical dysplasia (FCD). CD34 immunostained 75% of gangliogliomas (GG) and 60% of pleomorphic xanthoastrocytomas. FCD type IIIb [i.e. abnormal cortical layering associated with a glioneuronal tumor, according to the new International League Against Epilepsy (ILAE) classification] presented CD34-immunopositive cells in 2/9 (22.2%) cases, whereas FCD type II in 6/7 (85.7%) cases, a difference statistically significant (p = 0.0117). Bcl-2 immunostained 9/12 (75%) gangliogliomas and 2/3 (66.6%) gangliocytomas. The cases of FCD type IIIb resulted negative for Bcl-2, whereas 4/7 cases (57.1%) of FCD type II showed immunopositive cells. These differences in Bcl-2 expression between FCD type IIIb and FCD type II resulted statistically significant (p = 0.0088). Abnormal cortical layering, overall, represents the kind of FCD more commonly associated with seizure-related low-grade tumors, whereas FCD type II is more frequently associated with GG. The profile of CD34 and Bcl-2 expression exhibited by GG is more similar to that observed in FCD type II. Such immunoprofile suggests the existence of a common pathogenesis linking glioneuronal tumors and FCD type II.
authors.affiliation: Section of Pathology "M. Malpighi", Bellaria Hospital, University of Bologna, Italy. gianluca.marucci@ausl.bologna.it.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Marucci
authors.forename: Matteo
authors.initials: M
authors.lastname: Martinoni
authors.forename: Marco
authors.initials: M
authors.lastname: Giulioni
mesh_terms: D000293:Adolescent; D000328:Adult; D018952:Antigens, CD34 / Q000096:biosynthesis; D001927:Brain Diseases / Q000378:metabolism* / Q000473:pathology; D001932:Brain Neoplasms / Q000378:metabolism* / Q000473:pathology; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D054220:Malformations of Cortical Development / Q000378:metabolism* / Q000473:pathology; D065703:Malformations of Cortical Development, Group I; D008875:Middle Aged; D060787:Neoplasm Grading; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D018952:Antigens, CD34; D019253:Proto-Oncogene Proteins c-bcl-2