1Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California.
2Advanced Cancer Research Group, Kirkland, Washington.
J Natl Compr Canc Netw. 2023 Sep;21(9):945-950.e16. doi: 10.6004/jnccn.2023.7044.
Prophylactic growth-factor therapy with granulocyte colony-stimulating factor (G-CSF) reduces the risk of febrile neutropenia (FN) in patients with breast cancer initiating myelosuppressive chemotherapy. However, little is known about the protective benefit early in the chemotherapy cycle.
To assess the relationship between G-CSF prophylaxis and incidence of FN/infection in week 1 versus beyond week 1 of the first chemotherapy cycle, a retrospective study was conducted using Medicare claims from 2005 through 2020 among patients with breast cancer initiating high-risk chemotherapy. Two cohorts were compared based on G-CSF prophylaxis within 3 days following chemotherapy initiation. The primary outcome was FN or infection, defined as hospitalization with neutropenia, fever, or infection diagnosis. Secondary outcomes were a stricter definition of FN and infection-related hospitalization. Unadjusted and regression-adjusted proportions of patients experiencing each outcome during week 1 versus beyond week 1 of the first chemotherapy cycle were compared.
Of 78,810 patients meeting all inclusion criteria (>98% female; mean age, 69 years), 79% initiated TC (docetaxel/cyclophosphamide), 14% TCH (docetaxel/carboplatin/trastuzumab), and 7% TAC (docetaxel/doxorubicin/cyclophosphamide). Among patients receiving G-CSF (74%), incidence of first-cycle FN/infection was lower compared with patients not receiving G-CSF (overall, 6% vs 13%; TAC, 12% vs 19%; TC, 6% vs 12%; TCH, 5% vs 15%). However, patients who received G-CSF were generally more likely to experience FN/infection in week 1 (adjusted odds ratio [aOR], 1.24 for all; 1.73 for TAC; 1.35 for TC; and 0.76 for TCH). Results were similar for strictly defined FN (overall aOR, 1.29 for week 1 and 0.12 for beyond week 1) and infection-related hospitalization (overall aOR, 1.33 for week 1 and 0.27 for beyond week 1).
Overall, the rates of chemotherapy-related FN and infection in week 1 of the first chemotherapy cycle are similar for patients receiving and not receiving G-CSF, suggesting continued risk in week 1 despite prophylactic G-CSF.
粒细胞集落刺激因子（G-CSF）预防性治疗可降低开始骨髓抑制化疗的乳腺癌患者发热性中性粒细胞减少症（FN）的风险。然而，人们对化疗周期早期 G-CSF 预防的保护益处知之甚少。
为了评估 G-CSF 预防与首次化疗周期第 1 周与第 1 周以后 FN/感染发生率之间的关系，对 2005 年至 2020 年期间开始接受高风险化疗的乳腺癌患者进行了一项基于医疗保险索赔的回顾性研究。根据化疗开始后 3 天内是否接受 G-CSF 预防，比较了两组患者。主要结局为 FN 或感染，定义为中性粒细胞减少症、发热或感染诊断的住院。次要结局为更严格的 FN 和感染相关住院定义。比较了首次化疗周期第 1 周和第 1 周以后每个结局的患者比例。
在符合所有纳入标准的 78810 名患者中（>98%为女性；平均年龄 69 岁），79%的患者开始接受 TC（多西他赛/环磷酰胺），14%的患者开始接受 TCH（多西他赛/卡铂/曲妥珠单抗），7%的患者开始接受 TAC（多西他赛/多柔比星/环磷酰胺）。在接受 G-CSF 的患者中（74%），与未接受 G-CSF 的患者相比，首次化疗周期 FN/感染的发生率较低（总体为 6% vs 13%；TAC 为 12% vs 19%；TC 为 6% vs 12%；TCH 为 5% vs 15%）。然而，接受 G-CSF 的患者在第 1 周发生 FN/感染的可能性通常更高（所有患者调整后的优势比[aOR]为 1.24；TAC 为 1.73；TC 为 1.35；TCH 为 0.76）。严格定义 FN（总体 aOR 为第 1 周 1.29，第 1 周以后 0.12）和感染相关住院（总体 aOR 为第 1 周 1.33，第 1 周以后 0.27）的结果相似。
总的来说，接受和未接受 G-CSF 的患者在首次化疗周期第 1 周发生化疗相关 FN 和感染的发生率相似，提示尽管进行了预防性 G-CSF 治疗，但第 1 周仍存在持续风险。
