Analyzing Biological Factors Of Bone Metastases In Newly-diagnosis Breast Cancer

Objective: Recently,breast cancer is one of the highest incidence of female malignant tumors in the world.The most common metastasis site is bone,with an incidence of 65-75%.The propose of this study was to evaluate if and how different biological factors such as diagnosis of age,gender,race,histological grade,the operation of primary breast lesions and breast cancer subtypes influence the development of bone metastases.And the effective biological parameters can provide the reference for newly diagnosed bone metastases individualized as well as personalized prevention and treatment.Methods: This retrospective study included 8617 cases of stage IV metastatic breast cancer from 2010 to 2013 in the US SEER database,of which 5658 cases had bone metastases.Evaluating the predictive value of these factors in the newly diagnosed bone metastasis of breast cancer was accessed in Chi-square test,Logistic regression,Cox proportional hazards model and Kaplan-Meier survival curve.Results: In the HR+/HER-2+ breast cancer,there are 409 bone-only metastases(30.8%)and 442 bone+visceral metastases(33.3%).And in the HR+/HER-2-breast cancer,there are also 2126 bone-only metastases(46.4%)and 1280 bone+visceral metastasis(27.9%).Factors influencing the development of bone metastasis in breast cancer are age at diagnosis,BC subtypes,histological grade and race.The risk prognostic factors are elderly patients,no resection of the primary breast lesion,triple negative breast cancer,high-grade histological grade,and the blacks,which influence both the breast cancer-specific mortality and all-cause mortality.The leading risk factors: elderly patients(>80 years old)VS young patients(18-40 years old),HR=2.916,P<0.001,resection of the primary breast lesion VS no resection,HR=0.520,P<0.001,and triple negative BC VS HR+/HER-2+ BC,HR=3.452,P<0.001.There is statistically significant difference among different BC subtypes.The longest median survival time was 42 months for HR+/HER-2+ BC,while the shortest median survival time for HR-/HER-2-BC was 11 months.Surgical resection of primary breast lesions can significantly improve the survival of BC with bone metastases.The median survival time of surgery was 51 months,while the median survival time of non-surgical treatment was only 26 months.Conclusions: Hormone receptor positive BC is prone to metastasize to the bone.Young patients,HR+ breast cancer,low-grade histological grade and the Whites are the susceptibility factors of skeletal metastasis.The elderly patients,no resection of the primary breast lesions,triple negative breast cancer,high histological grade and the Blacks are the risk prognostic factors for breast cancer.It is recommended to strengthen the examinations about the bone metastases in the treatment and follow-up process,and actively take comprehensive treatment for these patients.