L W C Chow1,2,3, L Biganzoli4, A D Leo4, K Kuroi5, H S Han6, J Patel6, C S Huang7, Y S Lu8, L Zhu9, C Y C Chow3, W T Y Loo2,3, S Glück10, M Toi2,11. 1. State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute of Applied Medicine and Health, Macau University of Science and Technology, Macau. 2. Organisation for Oncology and Translational Research, Hong Kong. 3. UNIMED Medical Institute, Hong Kong. 4. Sandro Pitigliani Medical Oncology Unit, Hospital of Prato, Italy. 5. Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Tokyo, Japan. 6. Department of Women's Oncology, H. Lee Moffitt Cancer Center and Research Institute, USA. 7. Department of Surgery, National Taiwan University Hospital, Taiwan. 8. Department of Oncology, National Taiwan University Hospital, Taiwan. 9. Department of Surgery, Shanghai Jiao Tong University, Shanghai, China. 10. Sylvester Comprehensive Cancer Center, Leonard M. Miller School of Medicine, University of Miami, USA. 11. Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Abstract
AIM: For early-stage breast cancer, four cycles of docetaxel and cyclophosphamide (TC) was proven superior to doxorubicin plus cyclophosphamide in the US Oncology 9375 trial. Given primary prophylactic antibiotics, 5% febrile neutropenia was recorded in a population comprising 75.5% Caucasians. Smaller trials and retrospective studies reviewing TC use in Asian patients did not produce similar incidence rates. This study aims to discover the variable hematological toxicities with TC use in Caucasian and Asian patients. METHODS: Breast cancer data was retrospectively reviewed for patients receiving adjuvant docetaxel 60-75 mg/m2 plus cyclophosphamide 600 mg/m2 from six countries (China, Hong Kong, Japan, Taiwan, Italy, and United States). Similar number of patients with relatively balanced baseline characteristics were chosen for analysis of hematological and nonhematological toxicities and survival data. RESULTS: From March 2004 to July 2013, data of 227 patients (127 Asians and 100 Caucasian) patients were analyzed for treatment-related toxicities. During the four cycles of TC, Asians had a significantly higher rate of grade ≥2 neutropenia than Caucasians (45.7% vs 6.0%; P <0.001) and significantly more grade ≥3 neutropenia events were documented (respectively 30.7% vs 4.0%, P <0.001). The prophylactic use of G-CSF was similar; 26.0% in Asians and 28.0% in Caucasian (P = 0.764). There were no differences in nonhematological toxicities. No significant difference in disease-free survival was observed between Asians and Caucasians (log-rank P = 0.910). CONCLUSIONS: Ethnic differences in toxicity profile exist between Asian and Caucasian patients given adjuvant TC. Over 30% Asians but less than 5% Caucasians experienced grade ≥3 neutropenia.
AIM: For early-stage breast cancer, four cycles of docetaxel and cyclophosphamide (TC) was proven superior to doxorubicin plus cyclophosphamide in the US Oncology 9375 trial. Given primary prophylactic antibiotics, 5% febrile neutropenia was recorded in a population comprising 75.5% Caucasians. Smaller trials and retrospective studies reviewing TC use in Asian patients did not produce similar incidence rates. This study aims to discover the variable hematological toxicities with TC use in Caucasian and Asian patients. METHODS:Breast cancer data was retrospectively reviewed for patients receiving adjuvant docetaxel 60-75 mg/m2 plus cyclophosphamide 600 mg/m2 from six countries (China, Hong Kong, Japan, Taiwan, Italy, and United States). Similar number of patients with relatively balanced baseline characteristics were chosen for analysis of hematological and nonhematological toxicities and survival data. RESULTS: From March 2004 to July 2013, data of 227 patients (127 Asians and 100 Caucasian) patients were analyzed for treatment-related toxicities. During the four cycles of TC, Asians had a significantly higher rate of grade ≥2 neutropenia than Caucasians (45.7% vs 6.0%; P <0.001) and significantly more grade ≥3 neutropenia events were documented (respectively 30.7% vs 4.0%, P <0.001). The prophylactic use of G-CSF was similar; 26.0% in Asians and 28.0% in Caucasian (P = 0.764). There were no differences in nonhematological toxicities. No significant difference in disease-free survival was observed between Asians and Caucasians (log-rank P = 0.910). CONCLUSIONS: Ethnic differences in toxicity profile exist between Asian and Caucasian patients given adjuvant TC. Over 30% Asians but less than 5% Caucasians experienced grade ≥3 neutropenia.