Objective: There are different data in the literature about the consequences of the development of metastasis as de novo or recurrent. In this study, we retrospectively investigated the clinicopathologic and prognostic characteristics of HER-2 positive de novo and recurrent metastatic breast cancer patients. Material and Methods: The data of patients admitted to our clinic between 1996- 2017 were analysed retrospectively. The baseline features, treatments and survival data were recorded. Recurrent metastatic patients were further categorized as disease free interval 24 months. The features of two groups were analysed by Pearson chi-square test. Survival were calculated by using the Kaplan-Meier method with the Long-rank test. p
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 National Cancer Institute. Surveillance, Epidemiology, and End Results Program. SEER Stat Fact Sheets: Common Cancer Sites. https://seer.cancer.gov/statfacts/html/common.html. Published 2018. Accessed.
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