Haematologic toxicities associated with the addition of bevacizumab in cancer patients

Background: Bevacizumab is currently approved for the treatment of several malignancies. Haematologic toxicities are not among the main concerns associated with bevacizumab, but they have been occasionally reported. We performed a meta-analysis to determine the incidence and risk of haematologic toxicities associated with bevacizumab. Methods: Pubmed databases from 1966 to September 2010 were searched for studies reported, as well as American Society of Clinical Oncology meetings. Bevacizumab randomised clinical trials with adequate safety data profile were included. Statistical analyses were conducted to calculate the summary incidence, relative risk (RR) and 95% confidence intervals (CI). Results: 15,263 patients were included. The incidence of bevacizumab-associated all-grade and high-grade haematologic toxicities were, respectively: anaemia: 18.7% and 3.9%; neutropenia: 25.0% and 18.5%; and thrombocytopenia: 13.9% and 3.4%. Febrile neutropenia incidence was 3.8%. Compared to placebo/control arms, bevacizumab was associated with a decreased risk of all-grade (RR = 0.81; 95%CI 0.68-0.96; p = .016) and high-grade (RR = 0.73; 95%CI 0.60-0.89; p = .002) anaemia, and increased risks of all-grade (RR = 1.15; 95%CI 1.01-1.30; p = .033) and high-grade (RR = 1.08; 95%CI 1.02-1.13; p = .005) neutropenia, all-grade thrombocytopenia (RR = 1.22; 95%CI 1.00-1.48; p = .047) and febrile neutropenia (RR = 1.31; 95%CI 1.08-1.58; p = .006). Conclusions: Bevacizumab is associated with a lower risk of anaemia and increased risks of neutropenia, thrombocytopenia and febrile neutropenia.