MO2-4-2Cardiac monitoring among stage 0-III and stage IV breast cancer patients treated with trastuzumab

Abstract Background Trastuzumab has significantly improved the survival of HER2 positive breast cancer both in early stage and metastatic diseases. Cardiotoxicity is the major adverse event that limits the use of trastuzumab. Every guidelines recommend regular assessment of left ventricular ejection fraction (LVEF) at baseline and every 3 months during therapy for stage 0-III, and at baseline for stage IV. However, there are no large studies that describe current practice. Methods We used a database that linked the National Database of the Hospital-Based Cancer Registry (HBCR) and health insurance claims data from the Diagnosis Procedure Combination (DPC) survey. We collected claims data from October 2011 to December 2016 to allow inclusion of all treatments performed for breast cancers treated with trastuzumab newly diagnosed from 2012 to 2015. The annual echocardiogram examination rate in stage 0-III and stage IV were analyzed. We also explored factors associated with the performance of echocardiogram. Results In all, stage 0-III patients treated with trastuzumab were 18,968(12.7%) and mean age was 58(±12), stage IV patients treated with trastuzumab were 1,702(21.4%) and mean age was 58(±12). In stage 0-III, appropriate echocardiogram rate were increasing year by year (2012 13.4%, 2013 38.5%, 2014 40.3% and 2015 43%, p  Conclusion Appropriate echocardiogram rate improved, however a large proportion of patients still received suboptimal cardiac monitoring especially those among stage 0-III.