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Full-Text Articles in Medicine and Health Sciences

Automated Classification Of Breast Pathology Using Local Measures Of Broadband Reflectance, Ashley M. Laughney, Venkataramanan Krishnaswamy, Pilar Beatriz Garcia-Allende, Olga M. Conde, Wendy A. Wells, Keith D. Paulsen, Brian W. Pogue Nov 2010

Automated Classification Of Breast Pathology Using Local Measures Of Broadband Reflectance, Ashley M. Laughney, Venkataramanan Krishnaswamy, Pilar Beatriz Garcia-Allende, Olga M. Conde, Wendy A. Wells, Keith D. Paulsen, Brian W. Pogue

Dartmouth Scholarship

We demonstrate that morphological features pertinent to a tissue's pathology may be ascertained from localized measures of broadband reflectance, with a mesoscopic resolution (100-μm lateral spot size) that permits scanning of an entire margin for residual disease. The technical aspects and optimization of a k-nearest neighbor classifier for automated diagnosis of pathologies are presented, and its efficacy is validated in 29 breast tissue specimens. When discriminating between benign and malignant pathologies, a sensitivity and specificity of 91 and 77% was achieved. Furthermore, detailed subtissue-type analysis was performed to consider how diverse pathologies influence scattering response and overall classification efficacy. The …


Image Guided Near-Infrared Spectroscopy Of Breast Tissue In Vivo Using Boundary Element Method, Subhadra Srinivasan, Colin M. Carpenter, Hamid R. Ghadyani, Senate J. Taka, Peter A. Kaufman, Roberta M. Diflorio-Alexander, Wendy A. Wells, Brian W. Pogue, Keith D. Paulsen Nov 2010

Image Guided Near-Infrared Spectroscopy Of Breast Tissue In Vivo Using Boundary Element Method, Subhadra Srinivasan, Colin M. Carpenter, Hamid R. Ghadyani, Senate J. Taka, Peter A. Kaufman, Roberta M. Diflorio-Alexander, Wendy A. Wells, Brian W. Pogue, Keith D. Paulsen

Dartmouth Scholarship

We demonstrate quantitative functional imaging using image-guided near-infrared spectroscopy (IG-NIRS) implemented with the boundary element method (BEM) for reconstructing 3-D optical property estimates in breast tissue in vivo. A multimodality MRI-NIR system was used to collect measurements of light reflectance from breast tissue. The BEM was used to model light propagation in 3-D based only on surface discretization in order to reconstruct quantitative values of total hemoglobin (HbT), oxygen saturation, water, and scatter. The technique was validated in experimental measurements from heterogeneous breast-shaped phantoms with known values and applied to a total of seven subjects comprising six healthy individuals …


Breast Cancer Dna Methylation Profiles Are Associated With Tumor Size And Alcohol And Folate Intake, Brock C. Christensen, Karl T. Kelsey, Shichun Zheng, E. Andres Houseman, Carmen J. Marsit, Margaret R. Wrensch, Joseph L. Wiemels, Heather H. Nelson, Margaret R. Karagas Jul 2010

Breast Cancer Dna Methylation Profiles Are Associated With Tumor Size And Alcohol And Folate Intake, Brock C. Christensen, Karl T. Kelsey, Shichun Zheng, E. Andres Houseman, Carmen J. Marsit, Margaret R. Wrensch, Joseph L. Wiemels, Heather H. Nelson, Margaret R. Karagas

Dartmouth Scholarship

Although tumor size and lymph node involvement are the current cornerstones of breast cancer prognosis, they have not been extensively explored in relation to tumor methylation attributes in conjunction with other tumor and patient dietary and hormonal characteristics. Using primary breast tumors from 162 (AJCC stage I-IV) women from the Kaiser Division of Research Pathways Study and the Illumina GoldenGate methylation bead-array platform, we measured 1,413 autosomal CpG loci associated with 773 cancer-related genes and validated select CpG loci with Sequenom EpiTYPER. Tumor grade, size, estrogen and progesterone receptor status, and triple negative status were significantly (Q-values <0.05) associated with altered methylation of 209, 74, 183, 69, and 130 loci, respectively. Unsupervised clustering, using a recursively partitioned mixture model (RPMM), of all autosomal CpG loci revealed eight distinct methylation classes. Methylation class membership was significantly associated with patient race (P<0.02) and tumor size (P<0.001) in univariate tests. Using multinomial logistic regression to adjust for potential confounders, patient age and tumor size, as well as known disease risk factors of alcohol intake and total dietary folate, were all significantly (P<0.0001) associated with methylation class membership. Breast cancer prognostic characteristics and risk-related exposures appear to be associated with gene-specific tumor methylation, as well as overall methylation patterns.


Inspired Gas-Induced Vascular Change In Tumors With Magnetic-Resonance-Guided Near-Infrared Imaging: Human Breast Pilot Study, Colin M. Carpenter, Rebecca Rakow-Penner, Shudong Jiang, Bruce L. Daniel, Brian W. Pogue, Gary H. Glover, Keith D. Paulsen May 2010

Inspired Gas-Induced Vascular Change In Tumors With Magnetic-Resonance-Guided Near-Infrared Imaging: Human Breast Pilot Study, Colin M. Carpenter, Rebecca Rakow-Penner, Shudong Jiang, Bruce L. Daniel, Brian W. Pogue, Gary H. Glover, Keith D. Paulsen

Dartmouth Scholarship

This study investigates differences in the response of breast tumor tissue versus healthy fibroglandular tissue to inspired gases. Cycles of carbogen and oxygen gas are administered while measuring the changes with magnetic-resonance-guided near-infrared imaging in a pilot study of breast cancers. For two patients, analyses are performed with cross-correlation techniques, which measure the strength of hemodynamic modulation. The results show that the overall vasoresponse, indicated by total hemoglobin, of healthy tissue has approximately a 72% and 41% greater correlation to the gas stimulus than the tumor region, in two patients respectively, when background physiological changes are controlled. These data support …