Gastric malignancies in breast cancer survivors: Pathology and outcomes

Background: As the number of breast cancer survivors increases, the appearance of second malignancies and unusual metastatic patterns likely also is increasing. In particular, we and others have observed gastric malignancies in breast cancer survivors. Methods: We reviewed 3 regional hospital system tumor databases, comprising 19,049 analytic breast cancer cases, to determine the number, types, and outcomes of subsequent gastric malignancies. Results: Twenty-eight patients developed subsequent gastric malignancies, representing .15% of breast cancer survivors; 82% of patients had gastric symptoms. Overall survival for the cohort was 39%. Twenty-four patients (86%) had gastric primaries and 13 died of their second cancers. Four patients had gastric metastases; all had lobular histology in both their primary tumors and metastatic lesions. Five patients had gastrointestinal stromal tumors; all patients underwent resection and currently are alive. Conclusion: Gastric symptoms in breast cancer survivors may represent malignant lesions, often second primaries. All gastric metastases in our series were of lobular histology.