109P Updated long-term overall survival of older adjuvant ibandronate-treated patients with intermediate- or high-risk early breast cancer compared with additional adjuvant capecitabine treatment: The ICE randomized clinical trial

Abstract

The majority of breast cancers occur in women over the age of 65, but older breast cancer patients are largely underrepresented in clinical trials. We investigated the effect of adding capecitabine to adjuvant treatment with ibandronate in elderly breast cancer patients. The multicenter phase III ICE trial enrolled women ≥65 years with early node-positive/high-risk node-negative breast cancer and a Charlson Comorbidity Index (CCI) ≤2. Patients were randomized to capecitabine 2000 mg/m2 day 1-14 q3w for 6 cycles plus ibandronate (50 mg p.o. daily or alternatively 6 mg i.v. q4w) or ibandronate alone for 2 years. We present here an update on long-term follow-up for the secondary endpoint of overall survival (OS). 1358 (96.4%) from 1409 randomized patients started treatment. 564 (83.4%) completed 6 cycles of capecitabine. 513 (77.7%) and 516 (78.8%) completed ibandronate in the capecitabine/ibandronate and ibandronate arm, respectively. Median age was 71 (range 64-88) years, 1099 (81%) were hormone receptor (HR)-positive, 705 (51.9%) node-negative, 794 (58.5%) had a CCI of 0. HR-positive patients received additional adjuvant endocrine treatment. After an updated median follow-up time of 74 (IQR 56-126) months for OS in the entire cohort, 7-year OS was 83.5% for capecitabine/ibandronate versus 80.9% for ibandronate, and 10-year OS was 73.1% for capecitabine/ibandronate versus 70.8% for ibandronate (P=0.413). Lack of effect was independent from age, nodal and HR status. Addition of capecitabine caused significantly higher skin and gastrointestinal toxicities. The adjuvant combination of capecitabine and ibandronate did not show significantly better OS than ibandronate alone in elderly breast cancer patients.