Abstract PD3-7: Disease-free survival and Ki67 analysis of a randomized controlled trial comparing zoledronic acid plus chemotherapy with chemotherapy alone as a neoadjuvant treatment in patients with HER2-negative primary breast cancer (JONIE-1 study)

Abstract

Abstract Background: Zoledronic acid (ZOL) has been found to have a synergistic anti-proliferative effect when used in combination with antitumor drugs. We suggested that the addition of ZOL to neoadjuvant chemotherapy (CT) has potential anti-cancer benefit in postmenopausal patients with triple-negative breast cancer in JONIE-1 Trial (50% pCR rate in ZOL+CT: CTZ versus 0% in CT, p = 0.029). We analyzed the disease-free survival (DFS) as a secondary endpoint and baseline Ki67 levels between two groups. Methods: Women with Stage IIA-IIIB HER-2-negative breast cancer were randomly assigned 1:1 to CTZ group or CT group, CT was FEC100 q3w × 4 cycles followed by weekly paclitaxel for 12 cycles and ZOL 4mg was administered every 3-4 weeks. Among 188 patients recruited between March 2010 and April 2012 excluding 10 from the primary assessment, 178 patients were assessed. The aims of this study were to compare the relative efficacy or CTZ with the efficacy of CT in prolonging DFS in all patients and also to compare the pCR rates between baseline Ki67 high (20% and >20%) with Ki67 low (<20%) in ER positive cohort. Results: During a mean follow-up period of 34.4 months, breast cancer specific events (recurrence and death) occurred 17 participants, 7 in CTZ group and 10 in CT group. The 1-year, 2-year, and 3-year DFS rates were 97.7%, 88.4%, and 88.4% in CTZ versus 100%, 84.8%, and 81.1% in CT, respectively. In the ER positive cohort studied for Ki67 consist of 109 patients, 40 were in Ki67 low group and 69 were in Ki67 high group. Among Ki67 low group, number of pCR was none out of 18 in CTZ and 1 out of 22 in CT (p = .550). Among Ki high group, that was 6 out of 38 in CTZ and 3 out of 31 (p = .352). Conclusion: We could not find a modest improvement in disease-free survival compared the addition of ZOL to neoadjuvant CT with CT alone. Ki67 study for central analysis has been under investigation. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD3-7.