Secondary gastric cancer malignancies following a breast cancer diagnosis: A population-based analysis.

OBJECTIVE: To quantify the population-risk of developing gastric cancer (GC) following breast cancer (BC). METHODS: GC incidence following a ductal or lobular BC were separately compared to incidence in the general United States population using SEER data. RESULTS: GC rates were similar to the general population for ductal BC. Women aged 35-75 with lobular BC had a significantly higher incidence of GC; women aged 40-44 had the highest risk. CONCLUSION: The risk of secondary GC is high among young women diagnosed with lobular BC. More studies investigating the etiology and prevalence of familial GC syndromes at the population-level are needed.