Factors influencing bone metastasis in HER-2 negative breast cancer and the efficacy of capecitabine plus docetaxel

Purpose: The clinical data of HER-2 negative breast cancer patients were analyzed to investigate factors that influence bone metastasis. Methods: A total of 754 HER-2 negative breast cancer patients composed of the bone metastasis (237 patients) and non-bone metastasis (481 patients) group, were retrospectively and systematically evaluated for their clinicopathological characteristics, treatment modalities and their influencing factors. Both groups were administered a combined treatment of capecitabine and docetaxel and the statistical association between these factors and the development of bone metastases was investigated. Primary tumor location was identified through imaging while the hormone receptor status and tumour molecular classification were assessed by immunohistochemistry (IHC) on tumor samples and protein expression/genetic profiling, respectively. Results: A significant difference was seen between the groups in terms of T-stage, N-stage, hormone receptors, tumour molecular classification, axillary lymph node metastasis and quality of life scores (FACT-B) after combined therapy with capecitabine plus docetaxel (p < 0.05), while statistical significance was absent in terms of age and location of the primary site (p > 0.05). Furthermore, logistic regression analysis revealed that high T-stage, Luminal A molecular staging and the occurrence of axillary lymph node metastases were all risk factors for bone metastases in HER-2 negative breast cancer patients (p < 0.001). Conclusion: Combined therapy with capecitabine and docetaxel is effective in the treatment of bone metastases in patients with HER-2 negative breast cancer. A more comprehensive study involving a larger population of diverse patients will be conducted in the future to provide more reliable clinical data.