title: 3D MRI for Quantitative Analysis of Quadrant Percent Breast Density: Correlation with Quadrant Location of Breast Cancer.
abstract: Breast cancer occurs more frequently in the upper outer (UO) quadrant, but whether this higher cancer incidence is related to the greater amount of dense tissue is not known. Magnetic resonance imaging acquires three-dimensional volumetric images and is the most suitable among all breast imaging modalities for regional quantification of density. This study applied a magnetic resonance imaging-based method to measure quadrant percent density (QPD), and evaluated its association with the quadrant location of the developed breast cancer.
  
  
  
  A total of 126 cases with pathologically confirmed breast cancer were reviewed. Only women who had unilateral breast cancer located in a clear quadrant were selected for analysis. A total of 84 women, including 47 Asian women and 37 western women, were included. An established computer-aided method was used to segment the diseased breast and the contralateral normal breast, and to separate the dense and fatty tissues. Then, a breast was further separated into four quadrants using the nipple and the centroid as anatomic landmarks. The tumor was segmented using a computer-aided method to determine its quadrant location. The distribution of cancer quadrant location, the quadrant with the highest QPD, and the proportion of cancers occurring in the highest QPD were analyzed.
  
  
  
  The highest incidence of cancer occurred in the UO quadrant (36 out of 84, 42.9%). The highest QPD was also noted most frequently in the UO quadrant (31 out of 84, 36.9%). When correlating the highest QPD with the quadrant location of breast cancer, only 17 women out of 84 (20.2%) had breast cancer occurring in the quadrant with the highest QPD.
  
  
  
  The results showed that the development of breast cancer in a specific quadrant could not be explained by the density in that quadrant, and further studies are needed to find the biological reasons accounting for the higher breast cancer incidence in the UO quadrant.
authors.affiliation: Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, 164, Irvine Hall, Irvine, CA 92697-5020; Department of Radiology, E-Da Hospital and I-Shou University, Kaohsiung, Taiwan. Electronic address: jeonhc@uci.edu.
authors.forename: Jeon-Hor
authors.initials: JH
authors.lastname: Chen
authors.affiliation: Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, 164, Irvine Hall, Irvine, CA 92697-5020.
authors.forename: Fuyi
authors.initials: F
authors.lastname: Liao
authors.affiliation: Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, 164, Irvine Hall, Irvine, CA 92697-5020.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, 164, Irvine Hall, Irvine, CA 92697-5020.
authors.forename: Yifan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Radiological Technology, China Medical University, Taichung, Taiwan.
authors.forename: Chia-Ju
authors.initials: CJ
authors.lastname: Chang
authors.affiliation: Department of Radiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Chen-Pin
authors.initials: CP
authors.lastname: Chou
authors.affiliation: Department of Radiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Tsung-Lung
authors.initials: TL
authors.lastname: Yang
authors.affiliation: Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, 164, Irvine Hall, Irvine, CA 92697-5020.
authors.forename: Min-Ying
authors.initials: MY
authors.lastname: Su
mesh_terms: D000328:Adult; D000368:Aged; D001940:Breast / Q000000981:diagnostic imaging* / Q000473:pathology; D000071060:Breast Density; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged
keywords: Breast cancer; dense tissue; magnetic resonance imaging; quadrant percent density