Adjuvant trastuzumab in routine clinical practice and the impact of cardiac monitoring guidelines on treatment delivery.

Trastuzumab delivery and changes in left ventricular ejection fraction (LVEF) in 110 patients receiving adjuvant trastuzumab in routine practice are investigated. The potential impact of new, less stringent UK cardiac monitoring guidelines is examined. 86 patients (78%) completed trastuzumab on schedule. 11 (10%) completed treatment despite delay(s) to allow LVEF recovery, 7 (6%) discontinued trastuzumab because of insufficient LVEF recovery, 2 (2%) of whom developed symptomatic cardiotoxicity. 6 (5%) discontinued trastuzumab for non-cardiac reasons. With the newer guidelines, the value of LVEF lower limit of normal is important in determining the proportion of patients who require angiotensin-converting enzyme inhibitors (ACEIs) and cardiology referral: up to 100% could potentially complete trastuzumab on schedule with up to 60% receiving ACEIs and 25% requiring cardiology referral. Adjuvant trastuzumab was well tolerated overall. The new guidelines potentially allow more patients to complete trastuzumab on schedule but require higher levels of cardiological intervention.