Systematic review and meta-analysis of febrile neutropenia risk with TCH(P) in HER2-positive breast cancer

Background Docetaxel, carboplatin and trastuzumab, with or without pertuzumab (TCH(P)), has become the preferred (neo)adjuvant regimen for HER2-positive breast cancer. However, its associated febrile neutropenia (FN) risk is unclear: pivotal studies reported FN risks < 10%, but in clinical practice, a high FN rate (> 20%) was observed. This systematic review and meta-analysis determine the FN risk associated with TCH(P) and the indication for primary prophylactic granulocyte colony-stimulating factor (PP G-CSF). Methods The MEDLINE, Embase, Web of Science and Cochrane databases were searched for full-text English articles reporting the FN incidence in early breast cancer patients receiving (neo)adjuvant TCH(P). The primary endpoint was the pooled crude FN incidence in patients treated without PP G-CSF using the random effects method. Secondary endpoints were the FN risk with PP G-CSF support, age-related differences in FN and differences in risk with TCH versus TCHP. Results Seventeen studies were included in the systematic review. The pooled estimates of FN incidences were 27.6% (95% CI 18.6 to 37.1) in patients who did not receive PP G-CSF (primary meta-analysis, 9 studies, n = 889) versus 5.0% (95% CI 2.6 to 8.0) in patients administered PP G-CSF (secondary meta-analysis, 7 studies, n = 445). Two studies reported non-significant age-related differences in FN. The risk comparison between TCH and TCHP was inconclusive. Conclusions The crude FN risk associated with (neo)adjuvant TCH(P) is over 20%, the upper limit above which the international guidelines unanimously advise PP G-CSF administration. G-CSF prophylaxis effectively reduces FN risk and should become the standard of care with (neo)adjuvant TCH(P).