title: Diffusion changes precede size reduction in neoadjuvant treatment of breast cancer.
abstract: Traditionally, tumor response has been assessed via tumor size measurements during the course of a treatment. However, changes in these morphologically based measures occur relatively late in the course of a treatment. Alternative biomarkers are currently being evaluated to enable an earlier assessment of treatment to facilitate early cessation and cost savings. Diffusion-weighted imaging (DWI) has been identified by preclinical studies to be a likely alternative to tumor size measurements. In this study, 10 patients were examined prior to and after the first and second chemotherapy cycle time points. Longest diameter tumor measurements and apparent diffusion coefficients (ADCs) were recorded at each exam. An increase in the mean (normalized) ADC was noted as early as the first cycle time point. However, a reduction in the mean (normalized) longest diameter was only noted at the second cycle time point. Significant alterations from the baseline value were noted for ADC at the first (P=.005) and second cycle time points (P=.004). Longest diameter measurements only achieved a borderline significance at the second time point (P=.057). These results indicate that DWI may provide a suitable biomarker capable of providing an indication of response to treatment prior to tumor size measurements.
authors.affiliation: Centre for Magnetic Resonance Investigations, Division of Cancer, Postgraduate Medical School, University of Hull, HU3 2JZ Hull, UK. m.d.pickles@medschool.hull.ac.uk
authors.forename: Martin D
authors.initials: MD
authors.lastname: Pickles
authors.forename: Peter
authors.initials: P
authors.lastname: Gibbs
authors.forename: Martin
authors.initials: M
authors.lastname: Lowry
authors.forename: Lindsay W
authors.initials: LW
authors.lastname: Turnbull
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D017024:Chemotherapy, Adjuvant; D003520:Cyclophosphamide / Q000008:administration & dosage; D038524:Diffusion Magnetic Resonance Imaging; D015251:Epirubicin / Q000008:administration & dosage; D005260:Female; D006801:Humans; D020360:Neoadjuvant Therapy; D018709:Statistics, Nonparametric; D016896:Treatment Outcome
chemical_list: D015251:Epirubicin; D003520:Cyclophosphamide