Update on Neutropenia and the Use of Myeloid Growth Factors

s from the ASCO 40th Annual Meeting and the Multinational Association for Supportive Care in Cancer (MASCC)/International Society for Oral Oncology (ISOO) 16th International Symposium, both held earlier this year. The frequency of neutropenia in clinical practice remains alarmingly high, and the complications in terms of inpatient hospitalization, morbidity, mortality, and economic cost from the University HealthSystem Consortium database is staggering. In 2002, a second-generation granulocyte colony-stimulating factor (pegfilgrastim [Neulasta]) was approved for use in the prevention of chemotherapy-related neutropenia. Clinical benefit from a single injection postchemotherapy was equivalent to that of daily dosing for more than 10 days of filgrastim (Neupogen) in randomized trials.[4] In addition to the advantages of improved technology and better patient and provider convenience, subsequent clinical trials have not only helped us better understand the utility of pegfilgrastim, but also helped us refine our use of colonystimulating factors. Included in the 2004 ASCO/MASCC abstracts are important prospective studies that evaluate the benefits of filgrastim or pegfilgrastim in primary prevention of neutropenic complications in patient populations receiving chemotherapy where the risk of febrile neutropenia is substantially less than 40%. As the reader will see in the pages ahead, risk reduction may be even greater in these lower-risk myelosuppressive settings. In addition to improving our understanding of the epidemiology of neutropenia and its consequences and the ability to redefine our threshold of primary prophylaxis with colonystimulating factors, the 2004 ASCO and MASCC/ISOO abstracts also provide a wealth of information in the disease-specific areas of breast cancer, lung cancer, lymphoma, and hematologic malignancies. I invite the reader to review all of the sections carefully to better refine your understanding of the prevention and management of neutropenia in cancer chemotherapy patients within your own practice. In 2005 the ASCO guidelines will be updated, and we will see for the first time the National Comprehensive Cancer Network guidelines on the use of