A Retrospective Analysis Of The Risk Of Developing Second Primary Malignancy In Breast Cancer Patients Based On SEER Database

Objective:To analyze the clinicopathological features of primary breast cancer patients and to explore the risk factors of developing second primary malignancy in breast cancer patients.Methods:We utilized the Surveillance,Epidemiology and End Results database to construct a retrospective study of women diagnosed with a first primary,pathologically confirmed BC between January 1,2010 and December 31,2016.A total of 323,435 cases with first breast cancer were divided into two groups: single primary breast cancer and primary breast cancer with second cancer.The clinicopathological features in both two groups were compared.We evaluated the risk factors of developing a second primary cancer in breast cancer survivors.All analysis were performed with SPSS AU and SPSS software,version 23.0.The graphics were drawn using Python programming language.Standardized incidence ratios(SIRs)for second primary breast cancer patients were determined by the Multiple Primary Standardized Incidence Patios in SEER*Stat.The differences in the clinicopathological features between breast cancer patients with or without second cancer were analyzed by chi-square tests.Univariate and multivariate analysis of the risk factors of second breast cancer was performed by using Cox regression models and Poisson regression analysis was used to analyze the treatment-related factors separately.P values<0.05 was considered of statistical significance.Result:Total,323,435 female patients were enrolled in our study.There were 315,147 women with breast cancer only and 8,288 breast cancer survivors with second primary cancer in this database fitting our criteria.The average age of morbidity of two groups were 60.34 and 64.29 years old and the median age of them were 60 and 65 years old.The median survival time were 32 and 27 months.The average age at diagnosis of second primary cancer was 66.88 years old and the median age of them was 67 years old.Breast(27.56%)、lung and bronchus(13.26%)、corpus uteri(6.28%)、thyroid(5.76%)、 melanoma of the skin(4.59%)、 pancreas(3.81%)、 kidney(3.08%)、ovary(2.61%)、 urinary bladder(2.33%)and Hodgkin-nodal(2.11%)were the common sites which second primary preferentially occurs of primary breast cancer in decreasing order of frequency.The incidence of second primary cancer was positively correlated with older age,black race,widowed,unmarried or had domestic partner,other histologic type,triple negative breast subtype,undergoing partial mastectomy or modified radical mastectomy and radiotherapy.The risk related to American Indian or Alaska Native or underwent chemotherapy was relatively minor.Conclusion:1、The incidence of second primary cancer was positively correlated with older age,black race,widowed,unmarried or had domestic partner,other histologic type,triple negative breast subtype,undergoing partial mastectomy or modified radical mastectomy and radiotherapy.The risk related to American Indian or Alaska Native or underwent chemotherapy was relatively minor.2、Significant statistical differences were found in clinicopathological features between the two groups.It should be provided for the breast cancer patients who were in high-risk of developing second cancer more personalized cancer screening guidance.