title: Combined diffuse optical spectroscopy and contrast-enhanced magnetic resonance imaging for monitoring breast cancer neoadjuvant chemotherapy: a case study.
abstract: Monitoring tumor response to therapy can enable assessment of treatment efficacy, maximizing patient outcome and survival. We employ a noninvasive, handheld laser breast scanner (LBS) based on broadband diffuse optical spectroscopy (DOS) in conjunction with contrast-enhanced magnetic resonance imaging (cMRI) to assess tumor response to presurgical neoadjuvant chemotherapy. DOS and cMRI scans are performed after the first and fourth cycles of a doxorubicin/cyclophosphamide regimen in a patient with invasive ductal carcinoma. DOS measurements are used to quantify bulk tissue optical and physiological parameters, which are mapped to T2- and T1-weighted cMRI images. Initial DOS measurements show high tumor/normal contrast in total hemoglobin concentration (THC, 56+/-7 versus 27+/-4 microM) and water fraction (81.4+/-1% versus 24+/-3%) colocalized with regions of strongly enhancing T2-weighted and cMRI signals. After the fourth cycle of chemotherapy, we observe decreases in peak MRI contrast-enhancement values (37.6%) and apparent lesion volume (21.9 versus 13.7 cm3), which corresponds to physiological changes measured by DOS, including a 20 to 25% reduction in the spatial extent of the tumor and a 38.7% drop in mean total hemoglobin content (THC, 41.6 versus 23.4 microM). These data provide in vivo validation of the accuracy of broadband DOS and the sensitivity of optical methods to changes in tumor physiology.
authors.affiliation: University of California-Irvine, Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, Irvine, California 92162-1475, USA.
authors.forename: Natasha
authors.initials: N
authors.lastname: Shah
authors.forename: Jessica
authors.initials: J
authors.lastname: Gibbs
authors.forename: Dulcy
authors.initials: D
authors.lastname: Wolverton
authors.forename: Albert
authors.initials: A
authors.lastname: Cerussi
authors.forename: Nola
authors.initials: N
authors.lastname: Hylton
authors.forename: Bruce J
authors.initials: BJ
authors.lastname: Tromberg
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000188:drug therapy*; D044584:Carcinoma, Ductal / Q000175:diagnosis* / Q000188:drug therapy*; D017024:Chemotherapy, Adjuvant; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007834:Lasers; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013057:Spectrum Analysis / Q000379:methods*; D013382:Subtraction Technique; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA