title: Proton magnetic resonance spectroscopy predicts proliferative activity in diffuse low-grade gliomas.
abstract: The aim of the study was to investigate the ability of (1)HMRS to reflect proliferative activity of diffuse low-grade gliomas (WHO grade II). Between November 2002 and March 2007, a prospective study was performed on consecutive patients with suspected supratentorial hemispheric diffuse low-grade tumors. All the patients underwent MR examination using uniform procedures, and then surgical resection or biopsy within 2 weeks of the MR examination. Proliferative activity of the tumors was assessed by Ki-67 immunochemistry (Mb-1) on paraffin embedded tumor sections. Spectroscopic data was compared with Ki-67 labeling index and other histologic data such as histological subtype, cellular atypia, cellular density using univariate and multivariate analysis. 82 of 97 consecutive patients had histologically confirmed WHO grade 2 gliomas. Ki-67 proliferation index (PI) was correlated with specific spectral patterns: (1) low PI (<4%) was associated with increased Cho/Cr and absence of both free lipids or lactates; (2) intermediate PI (4-8%) was associated with resonance of lactates; and (3) high PI (>8%) was characterized by a resonance of free lipids. On multivariate analysis, resonance of lactates and resonance of free lipids appeared as independent predictors of intermediate PI (P < 0.001) and high PI (P < 0.001), respectively; moreover, free lipids resonance was correlated with cellular atypia (P < 0.05). This study suggests that (1)HMRS is a reliable tool to evaluate the proliferation activity of WHO grade 2 glioma and to identify potentially more aggressive clinical behavior.
authors.affiliation: Department of Neuroradiology, Pitié Salpêtrière Hospital, Paris, France. remy.guillevin@psl.aphp.fr
authors.forename: Remy
authors.initials: R
authors.lastname: Guillevin
authors.forename: Carole
authors.initials: C
authors.lastname: Menuel
authors.forename: Hugues
authors.initials: H
authors.lastname: Duffau
authors.forename: Michel
authors.initials: M
authors.lastname: Kujas
authors.forename: Laurent
authors.initials: L
authors.lastname: Capelle
authors.forename: Agnès
authors.initials: A
authors.lastname: Aubert
authors.forename: Sophie
authors.initials: S
authors.lastname: Taillibert
authors.forename: Ahmed
authors.initials: A
authors.lastname: Idbaih
authors.forename: Joan
authors.initials: J
authors.lastname: Pallud
authors.forename: Giovanni
authors.initials: G
authors.lastname: Demarco
authors.forename: Robert
authors.initials: R
authors.lastname: Costalat
authors.forename: Khê
authors.initials: K
authors.lastname: Hoang-Xuan
authors.forename: Jacques
authors.initials: J
authors.lastname: Chiras
authors.forename: Jean-Noel
authors.initials: JN
authors.lastname: Vallée
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000175:diagnosis*; D049109:Cell Proliferation; D005260:Female; D005910:Glioma / Q000175:diagnosis*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D011522:Protons
chemical_list: D019394:Ki-67 Antigen; D011522:Protons