Little Patient Benefit to Using G-CSF to Prevent Neutropenia

There is little patient benefit to using granulocyte colony-stimulating factor (G-CSF) to help white blood cell growth and reduce the risk of infection in women with breast cancer, according to a study published in Journal of Clinical Oncology.

The American Society of Clinical Oncology recommends, through the Choosing Wisely campaign, that oncologists do not use G-CSF to prevent neutropenia in patients with less than a 20% risk of getting an infection. The purpose of this study was to quantify, by chemotherapy regimen, the “correlation between neutropenia-related hospitalization and G-CSF administration.” Three regimens were studied: docetaxel and cyclophosphamide (TC); docetaxel, carboplatin, and trastuzumab (TCH); and doxorubicin and cyclophosphamide.

“In women with breast cancer treated with a conventional dose of doxorubicin and cyclophosphamide, a chemotherapy regimen that has low risk of infection, more than half of them were also treated with G-CSF, with no benefit,” Abiy Agiro, lead author and research manager for HealthCore, said in a statement. “This is unfortunate, especially given that patients can experience uncomfortable side effects from G-CSF, such as bone pain, headache, and nausea. When the chemotherapy risk for neutropenia is low, these high-cost agents place an unnecessary burden on the healthcare system without providing a discernable benefit to the patient.”

The analysis included patients with breast cancer who began first-cycle chemotherapy from 2008 to 2013. Overall, 4815 patients received TC; 2292 received TCH; and 1638 patients received doxorubicin and cyclophosphamide.

Overall, the G-CSF therapy was associated with some reductions in neutropenia-related hospitalizations in the TC and TCH treatment groups. Meanwhile, patients receiving doxorubicin and cyclophosphamide with G-CSF actually had a slightly higher rate of neutropenia compared with patients not taking any G-CSF. However, the difference was not statistically significant.

The researchers also determined that, despite guidelines regarding appropriate use of G-CSF, it is still commonly used in regimens that do not have a high risk for inducing neutropenia-related complications.

“This study confirms previous trials that have shown that G-CSF is effective at decreasing fever and infections with higher-risk chemotherapy treatments but failed to show any benefit with lower-risk regimens,” said Gary Lyman, MD, MPH, co-director of the Hutchinson Institute of Cancer Outcomes Research for the Fred Hutchinson Cancer Research Center. “The study also showed that older age was associated with increased risk of neutropenia-related hospitalization, however the healthcare community needs to study G-CSF further to better understand which patients on which chemotherapies can benefit most.”