Toxicity of docetaxel plus cyclophosphamide as adjuvant therapy for breast cancer in Chinese patients - the Hong Kong experience

Abstract

Aims: The docetaxel and cyclophosphamide (TC) regimen is increasingly popular as adjuvant chemotherapy for operable breast cancers. We conducted a retrospective study in Hong Kong to evaluate the toxicity of this regimen in Chinese patients. Methods: Between January 2007 and May 2008 76 female Chinese patients with resected stage I–III operated invasive breast cancer were treated with 4 cycles of TC (75 and 600 mg/m2, respectively, administered i.v. every 3 weeks for four cycles) in two public regional cancer centers of Hong Kong. A total of 24 (32%) patients also received primary prophylactic ciprofloxacin (500 mg twice daily, day 5–14). Chemotherapy-related toxicities were graded by the CTCAE version 3.0. Results: The median age was 50 (range 26–67). A total of 68 (89%) patients successfully completed four cycles of chemotherapy. 72 (95%) and 16 (21%) patients developed grade 3–4 neutropenia and febrile neutropenia (FN) infection, respectively, in one or more cycles. However, no grade 3–4 anemia or thrombocytopenia events were observed. Other grade 3–4 non-hematological toxicities were also uncommon, apart from allergic reactions in two (3%) patients. No viral reactivation was observed among the 8 hepatitis B carriers. Patients with prophylactic ciprofloxacin had less grade 3–4 FN infection (13% vs 25%, P = 0.214) and a higher chance of receiving the full scheduled dose (88% vs 62%, P = 0.045) than patients without. Conclusion: The myelotoxicity of TC was substantially higher in Chinese patients compared with non-Chinese patients in developed countries. Routine prophylactic measures are recommended to maintain the dose levels and reduce the risk of FN.