title: Tumor apparent diffusion coefficient as an imaging biomarker to predict tumor aggressiveness in patients with estrogen-receptor-positive breast cancer.
abstract: The purpose of this retrospective study was to evaluate whether tumor apparent diffusion coefficient (ADC) was correlated with pathologic biomarkers such as tumor cellularity, Ki67, tumor-infiltrating lymphocytes (TILs), and peritumoral lymphocytic infiltrate (PLI) in patients with estrogen receptor (ER)-positive breast cancer. The study was approved by the institutional review board and informed consent was waived. From July 2014 to December 2014, we reviewed 140 ER-positive tumors in 138 consecutive patients (range, 28-77 years; mean, 52 years) who underwent preoperative breast MRI and definitive surgery. All patients underwent diffusion-weighted imaging with a 3T scanner. Two radiologists drew the region of interest of the entire tumor and obtained the mean and pixel-based histogram of ADC. On pathology, two pathologists reviewed tumor cellularity, Ki67, TILs, and PLI. Multiple linear regression analysis was used to determine pathologic variables independently associated with ADC. Tumors with high tumor cellularity and high Ki67 had significantly lower ADCs than those with low tumor cellularity and low Ki67 (P < 0.05 for all). Tumors without PLI had significantly higher standard deviation than those with PLI (0.23 ± 0.08 versus 0.18 ± 0.05; P < 0.001). Median ADC was negatively correlated with tumor cellularity (r = -0.441), and Ki67 (r = -0.382). The standard deviation of ADC was also negatively correlated with the degree of PLI (r = -0.319). On multivariate linear regression analysis, tumor cellularity and Ki67 were independently associated with tumor ADC. Tumor ADC would be an MRI biomarker for the prediction of tumor aggressiveness indicators such as Ki67, tumor cellularity, and PLI in ER-positive breast cancer. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: Hee Jung
authors.initials: HJ
authors.lastname: Shin
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: So Hee
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Pathology, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Pathology, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: Gyungyub
authors.initials: G
authors.lastname: Gong
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: Seunghee
authors.initials: S
authors.lastname: Baek
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Chae
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: Woo Jung
authors.initials: WJ
authors.lastname: Choi
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: Joo Hee
authors.initials: JH
authors.lastname: Cha
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Songpa-gu, Seoul, South Korea.
authors.forename: Hak Hee
authors.initials: HH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology*; D004058:Diffusion; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019394:Ki-67 Antigen / Q000378:metabolism*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011960:Receptors, Estrogen / Q000378:metabolism; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D011960:Receptors, Estrogen
keywords: Ki67; breast neoplasm; diffusion-weighted imaging; tumor cellularity