Bone metastasis: evaluation of 1100 patients with breast cancer

The aim of this study is to determine the relationship between the demographics and the clinical characteristics of breast cancer (BC) patients with bone metastasis (BM). The study included 1100 BC patients, of whom 174 had BMs and 926 had no BMs. Immunohistochemical methods were employed to understand estrogen receptor (ER)/progesterone receptor (PgR) receptor levels, Ki-67 protein levels and human epidermal growth factor receptor 2 (HER2) expression levels. Data were collected based on the hospital records of these patients, and ultrasonography or magnetic resonance imaging (MRI) results were employed for tumor localization. Positron emission tomography (PET)-computed tomography (CT) data were employed for the BM evaluation. The mean age (P = 0.067) and tumor diameter (P = 0.022) of BC cases who showed BM were significantly different from those who did not show BM. In addition, a significant relationship between the tumor diameter (P = 0.001) and axillary lymph node (ALN) number (P = 0.000) and BM was observed. The percentages of ER and PgR (r = 0.639; P = 0.000) were positively correlated, while the percentage of ER and Ki-67 protein levels (r = -0.505; P = 0.000) were negatively correlated. However, these correlations were not significant between the groups. The tumor diameter and positive ALNs may have an important role in BM of BC. There was no significant effect of ER/PgR receptor levels, Ki-67 protein levels, or HER2 expression levels in BMs of BC.