title: Monitoring breast tumor progression by photoacoustic measurements: a xenograft mice model study.
abstract: The current study reports the photoacoustic spectroscopy-based assessment of breast tumor progression in a nude mice xenograft model. The tumor was induced through subcutaneous injection of MCF-7 cells in female nude mice and was monitored for 20 days until the tumor volume reached 1000  mm3. The tumor tissues were extracted at three different time points (days 10, 15, and 20) after tumor inoculation and subjected to photoacoustic spectral recordings in time domain ex vivo at 281 nm pulsed laser excitations. The spectra were converted into the frequency domain using the fast Fourier transformed tools of MATLAB® algorithms and further utilized to extract seven statistical features (mean, median, area under the curve, variance and standard deviation, skewness and kurtosis) from each time point sample to assess the tumor growth with wavelet principal component analysis based logistic regression analysis performed on the data. The prediction accuracies of the analysis for day 10 versus day 15, day 15 versus day 20, and day 10 versus day 20 were found to be 92.31, 87.5, and 95.2%, respectively. Also, receiver operator characteristics area under the curve analysis for day 10 versus day 15, day 15 versus day 20, and day 10 versus day 20 were found to be 0.95, 0.85, and 0.93, respectively. The ability of photoacoustic measurements in the objective assessment of tumor progression has been clearly demonstrated, indicating its clinical potential.
authors.affiliation: Manipal University, School of Life Sciences, Department of Biophysics, Manipal, Karnataka 576 104, India.
authors.forename: Mallika
authors.initials: M
authors.lastname: Priya
authors.affiliation: Manipal University, School of Life Sciences, Department of Radiation Biology and Toxicology, Manipal, Karnataka 576 104, India.
authors.forename: Bola Sadashiva
authors.initials: BS
authors.lastname: Satish Rao
authors.affiliation: Manipal University, School of Life Sciences, Department of Biophysics, Manipal, Karnataka 576 104, India.
authors.forename: Subhash
authors.initials: S
authors.lastname: Chandra
authors.affiliation: Manipal University, School of Life Sciences, Department of Biophysics, Manipal, Karnataka 576 104, IndiacManipal University, Manipal Institute of Technology, Department of Electronics & Communications, Manipal, Karnataka 576 104, India.
authors.forename: Anirbit
authors.initials: A
authors.lastname: Datta
authors.affiliation: Manipal University, Manipal Institute of Technology, Department of Electronics & Communications, Manipal, Karnataka 576 104, India.
authors.forename: Subramanya G
authors.initials: SG
authors.lastname: Nayak
authors.affiliation: Manipal University, School of Life Sciences, Department of Biophysics, Manipal, Karnataka 576 104, India.
authors.forename: Krishna Kishore
authors.initials: KK
authors.lastname: Mahato
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000473:pathology*; D045744:Cell Line, Tumor; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation* / Q000379:methods*; D061986:MCF-7 Cells; D051379:Mice; D008819:Mice, Nude; D009361:Neoplasm Invasiveness; D061088:Photoacoustic Techniques / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity