title: The Association Between Body Size and Breast Cancer in Han Women in Northern and Eastern China.
abstract: BACKGROUND
  Although obesity has been reported worldwide as a risk factor for breast cancer, there are still some inconsistencies regarding the association between obesity and breast cancer. Body mass index (BMI) is used most to assess the extent of obesity; however, the association of other body size characteristics, such as waist and hip circumference, with susceptibility to breast cancer in Chinese Han women needs to be better assessed.
  
  
  METHODS
  Female Chinese Han patients (N= 2,800) were recruited from 21 hospitals in northern and eastern China from April 2012 to April 2013 for a case-control study. The significant differences of factors related to body size between the breast-cancer case and control groups were determined by Student'sttest and chi-square tests.
  
  
  RESULTS
  Premenopausal women with breast cancer had higher BMI and larger waist and hip circumferences (p= 2 × 10-4, <1 × 10-6, and 2 × 10-5, respectively). However, these body-size factors were not associated with postmenopausal breast cancer (p= .45, 0.32, and 0.12, respectively). BMI between 28 and 30 kg/m2or greater than 32 kg/m2was related to breast cancer incidence in the overall study population and in premenopausal women but not in the postmenopausal group.
  
  
  CONCLUSIONS
  Obesity is significantly associated with breast cancer in Chinese Han premenopausal women but not in postmenopausal women. Thus, it is important to realize that weight control, as well as avoiding abdominal obesity, should be considered as one of the most effective methods of reducing breast cancer risk.
  
  
  CONCLUSIONS
  To better understand the characteristics and risk factors for breast cancer in Han women in northern and eastern China, a case-control study of 2,800 Chinese Han women was conducted. Obesity was significantly associated with breast cancer in Chinese Han premenopausal women but not in postmenopausal women. Consequently, controlling body weight and avoiding abdominal obesity should be considered as one of the most effective methods of reducing breast cancer susceptibility. However, the diversity between this study's finding among Chinese Han women and other data previously reported among European and American populations still needs further investigation.
authors: Department of Breast Surgical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
authors: Xin
authors: X
authors: Wang
authors: Department of Breast Surgery, The Second Hospital of Shandong University, Jinan, Shandong, People's Republic of China.
authors: Liang
authors: L
authors: Li
authors: Department of Breast Surgical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
authors: Jidong
authors: J
authors: Gao
authors: Department of Breast Surgical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
authors: Jiaqi
authors: J
authors: Liu
authors: Department of Breast Surgery, The Second Hospital of Shandong University, Jinan, Shandong, People's Republic of China.
authors: Mingming
authors: M
authors: Guo
authors: Department of Breast Surgery, The Second Hospital of Shandong University, Jinan, Shandong, People's Republic of China.
authors: Liyuan
authors: L
authors: Liu
authors: Department of Breast Surgical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
authors: Wenyan
authors: W
authors: Wang
authors: Department of Breast Surgical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
authors: Jie
authors: J
authors: Wang
authors: Department of Breast Surgical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
authors: Zeyu
authors: Z
authors: Xing
authors: Department of Breast Surgery, The Second Hospital of Shandong University, Jinan, Shandong, People's Republic of China yzg@medmail.com.cn xiangw@vip.sina.com.
authors: Zhigang
authors: Z
authors: Yu
authors: Department of Breast Surgical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China yzg@medmail.com.cn xiangw@vip.sina.com.
authors: Xiang
authors: X
authors: Wang
keywords: Body mass index; Breast cancer; Chinese Han population; Menopause