Abstract P3-15-02: Underreporting of Myelotoxicity with Emerging Breast Cancer Regimens

Background: Although many emerging regimens that incorporate targeted agents may produce increased myelosuppressive side-effects, clinical data guiding colony-stimulating factor (CSF) use with these regimens are not readily available. This review assessed the reporting diligence around febrile neutropenia and the related use of CSF and antibiotics in published clinical trials evaluating emerging regimens for breast cancer treatment. Methods: We searched Medline, EMBASE, and Cochrane databases to identify randomized, controlled phase 3 breast cancer studies published between Jan 2005 and June 2009. After excluding trials of vaccines, hormonal therapy alone, and stem cell transplantation/mobilization, corresponding publications were retrieved and data extracted on the incidence of neutropenia and its complications and CSF/antibiotic use. We then calculated the percentage of these publications that reported each outcome. Results: Of 463 trials identified from the search, only 73 met the inclusion criteria. Overall, 70% and 55% of trials reported the incidence of grade 3/4 neutropenia and febrile neutropenia, respectively (Table). Neutropenia-related hospitalizations were reported in 3% of trials. Prophylactic use of CSF and antibiotics was defined in the methods section of 59% and 23% of trials, respectively; and only reported in the results section of 22% and 5% of trials, respectively. Conclusion: Clinically significant neutropenia and neutropenia-related events (including febrile neutropenia) were generally described in the studies evaluated; however, the reported use of CSF and/or antibiotics was infrequent and inconsistent in the published literature of emerging regimens. A standardized approach to reporting neutropenic outcomes as well as the use of supportive care measures can assist cliniciansto prospectively manage the relevant toxicities associated with these emerging regimens and thereby facilitate their safe and effective use in clinical practice. Table: Reporting of myelotoxicity data in published phase 3 trials CSF = colony-stimulating factor Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-15-02.