title: Evaluation of diffusion parameters as early biomarkers of disease progression in glioblastoma multiforme.
abstract: The purpose of this study was to evaluate diffusion parameters at pre-, mid-, and post-radiation therapy (RT) in contrast-enhancing and nonenhancing lesions of postsurgical glioblastoma multiforme patients treated with the standard of care RT concurrently with temozolomide (TMZ) followed by adjuvant TMZ and an antiangiogenic drug. The diffusion parameters explored include baseline and short-term changes in apparent diffusion coefficient, fractional anisotropy, and eigenvalues. These diffusion parameters were examined as early markers for disease progression by relating them to clinical outcome of 6-month progression-free survival. The results indicated that changes from mid- to post-RT were significantly different between patients who progressed within 6 months vs those who were free of progression for 6 months after initiation of therapy. The study also showed that the changes in diffusion parameters from the mid- to post-RT scan may be more significant than those from pre- to mid-RT and pre- to post-RT. This is important because the mid-RT scan is currently not performed as part of the standard clinical care.
authors.affiliation: UCSF/UCB Joint Graduate Group in Bioengineering, Department of Radiology and Biomedical Imaging, University of California-San Francisco, San Francisco, California 94158-2330, USA. inas.khayal@radiology.ucsf.edu
authors.forename: Inas S
authors.initials: IS
authors.lastname: Khayal
authors.forename: Mei-Yin C
authors.initials: MY
authors.lastname: Polley
authors.forename: Llewellyn
authors.initials: L
authors.lastname: Jalbert
authors.forename: Adam
authors.initials: A
authors.lastname: Elkhaled
authors.forename: Susan M
authors.initials: SM
authors.lastname: Chang
authors.forename: Soonmee
authors.initials: S
authors.lastname: Cha
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Butowski
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Nelson
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000032:analysis*; D001932:Brain Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D003131:Combined Modality Therapy; D003606:Dacarbazine / Q000031:analogs & derivatives / Q000627:therapeutic use; D056324:Diffusion Tensor Imaging; D018450:Disease Progression; D018572:Disease-Free Survival; D005909:Glioblastoma / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D006801:Humans; D011379:Prognosis; D011878:Radiotherapy; D000077204:Temozolomide
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D003606:Dacarbazine; D000077204:Temozolomide