Initial outcomes analysis for large multicenter integrated cancer network implementation of intensity modulated radiation therapy for breast cancer.

To analyze the initial clinical outcomes for breast cancer patients treated with intensity-modulated radiation therapy (IMRT) in a large integrated cancer center network. A total of 495 patients with breast cancer received IMRT following breast conserving surgery among nine cancer centers. Seven community cancer centers span a 100-mile radial distance from the two central academic sites. All nine cancer centers followed the same clinical pathway guidelines for the radiotherapeutic management of breast cancer. IMRT planning for all centers was performed at one central location, D3 Advanced Radiation Planning Service. The median IMRT prescription dose was 50 Gy followed by a boost with median dose of 10 Gy. The median breast volume was 918 cm(3). The median Dose Homogeneity Index (DHI) was 93%. The median % of ipsilateral lung volume receiving >20 Gy was 4.6%. For left breast IMRT, the median % heart volume receiving more than 5% of prescription dose was 13.1. There was no statistical difference in the mean DHI, heart and lung dose between the academic and community sites. For all patients, NCI CTC Grades 0,1,2,3 for acute skin erythema was 16%, 55%, 28%, and 1%, respectively. The rates of Grade 0,1,2,3 acute skin desquamation were 75%, 20%, 4%, and 1%, respectively. There was no statistically significant difference in acute skin toxicities (>grade 2) among the academic and community cancer centers. With centralized processes, IMRT can be safely and effectively delivered in a large health system with an admixture of academic and community centers but long-term follow-up is necessary.