title: Surgery time interval and molecular subtype may influence Ki67 change after core needle biopsy in breast cancer patients.
abstract: BACKGROUND
  To investigate the accuracy of core needle biopsy (CNB) in evaluating breast cancer estrogen receptor (ER), progesterone receptor (PR), HER2, and Ki67 status and to identify factors which might be associated with Ki67 value change after CNB.
  
  
  METHODS
  A retrospective study was carried out on 276 patients with paired CNB and surgically removed samples (SRS). Clinico-pathological factors as well as the surgery time interval (STI) between CNB and surgery were analyzed to determine whether there were factors associated with Ki67 value change after CNB. Five tumor subtypes were classified as follows: Luminal A, Luminal B-HER2-, Luminal B-HER2+, Triple Negative (TN), and HER2+. Ki67 value change was calculated as SRS minus CNB.
  
  
  RESULTS
  Mean STI after CNB was 4.5 (1-37) days. Good agreement was achieved for ER, PR, and HER2 evaluation between CNB and SRS. However, Ki67 expression level was significantly higher in SRS compared with CNB samples: 29.1 % vs. 26.2 % (P < 0.001). Both univariate and multivariate analysis demonstrated that STI and molecular subtype were associated with a Ki67 change after CNB. Luminal A tumors experienced more Ki67 elevation than Luminal B-HER2- diseases (6.2 % vs -0.1 %, P = 0.014). Patients with longer STI after CNB had a higher Ki67 increase: -1.1 % within 1-2 days, 2.1 % with 3-4 days, and 5.6 % more than 4 days, respectively (P = 0.007). For TN and HER2+ tumors, the Ki67 change was apt to be 0 with STI ≤ 4 days, while a >7 % Ki67 increase was noticed in patients with STI ≥ 5 days.
  
  
  CONCLUSIONS
  CNB was accurate in evaluating ER, PR, HER2, and molecular subtype status. Ki67 value significantly increased after CNB, which was associated with STI and molecular subtype. Further translational research needs to consider Ki67 changes following CNB among different breast cancer molecular subtypes.
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. chenxiaosong0156@hotmail.com.
authors.forename: Xiaosong
authors.initials: X
authors.lastname: Chen
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. sjzhu@126.com.
authors.forename: Siji
authors.initials: S
authors.lastname: Zhu
authors.affiliation: Department of Pathology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China. XCF@126.com.
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Fei
authors.affiliation: University of Colorado Comprehensive Cancer Center, Aurora, CO, 80045, USA. david.garfield@earthlink.net.
authors.forename: David H
authors.initials: DH
authors.lastname: Garfield
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. wjyb1011@rjh.com.cn.
authors.forename: Jiayi
authors.initials: J
authors.lastname: Wu
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. ho11649@rjh.com.cn.
authors.forename: Ou
authors.initials: O
authors.lastname: Huang
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. lyf10313@rjh.com.cn.
authors.forename: Yafen
authors.initials: Y
authors.lastname: Li
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. LH11068@rjh.com.cn.
authors.forename: Li
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. HJR11038@rjh.com.cn.
authors.forename: Jianrong
authors.initials: J
authors.lastname: He
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. cwg@rjh.com.cn.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Chen
authors.affiliation: Department of Pathology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China. Jinxiaolong@126.com.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Jin
authors.affiliation: Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai, 20025, China. kwshen@medmail.com.cn.
authors.forename: Kunwei
authors.initials: K
authors.lastname: Shen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D014408:Biomarkers, Tumor; D062005:Biopsy, Large-Core Needle; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000601:surgery*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008875:Middle Aged; D060787:Neoplasm Grading; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012307:Risk Factors; D013997:Time Factors; D047368:Tumor Burden; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone