[Protocol for administration of trastuzumab based on cardiac function].

We analyzed 7 patients with breast cancer who suffered from trastuzumab-associated cardiac dysfunction. Left ventricular ejection fraction (EF) was calculated by M-mode echocardiography. We propose a protocol for the administration of trastuzumab based on EF in the clinical courses of the 7 patients and the literatures concernig trastuzumab. If the EF is ≥60%, an echocardiography is performed every 3 months during trastuzumab therapy. If the EF is ≥53% and ≤60%, an echocardiography is performed every 2 months. If the EF is ≤53%, an echocardiography is performed more frequently. If the EF decreases by ≥10% from its previous level, an echocardiography is performed after 3 weeks. Also, trastuzumab is withheld when the EF falls to ≤45%. When the EF falls to ≤40%, the standard treatment for congestive heart failure is initiated. An echocardiography is performed every 2 weeks after trastuzumab is withheld. Trastuzumab therapy can be resumed if the EF improves to ≥50%.