Division of Pharmaceutical, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka, Osaka 541-8567, Japan.
Department of Thoracic Oncology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka, Osaka 541-8567, Japan.
Cancer Treat Res Commun. 2024;40:100836. doi: 10.1016/j.ctarc.2024.100836. Epub 2024 Jul 30.
The most recommended treatment for stage IV EGFR-positive lung cancer is osimertinib monotherapy. The dosage of osimertinib is fixed at 80 mg/day regardless of body surface area (BSA), however some patients withdraw or reduce the dosage due to adverse events (AEs).
We performed a retrospective cohort study of 98 patients with EGFR mutation-positive non-small cell lung cancer (NSCLC), who received 80 mg osimertinib as the initial treatment. We investigated the impact of BSA on efficacy and safety of osimertinib.
The cut-off value of BSA was estimated using the receiver operating characteristics curve, and was determined to be 1.5 m. There were 44 patients in the BSA < 1.5 group and 54 patients in the BSA ≥ 1.5 group. There was no significant difference in the incidence of AEs (hematologic toxicity of ≥grade 3 or higher, and non-hematologic toxicity of ≥grade 3) between the two groups. However, the incidence of dose reduction due to AEs was significantly higher in the BSA < 1.5 group compared with the BSA ≥ 1.5 group (16 patients vs 5 patients, p = 0.003). The main reasons were fatigue, anorexia, diarrhea, and liver disfunction. Median progression-free survival (PFS) was not significantly different (16.9 months in the BSA < 1.5 group vs 18.1 months in the BSA ≥ 1.5 group, p = 0.869).
Differences in BSA affected the optimal dose of osimertinib. However, the PFS with osimertinib treatment was not affected by BSA. Therefore, when using osimertinib as an initial treatment for patients with EGFR-mutant NSCLC, dose reduction to control AEs should be considered, especially in the BSA<1.5 group.
对于 IV 期 EGFR 阳性肺癌，最推荐的治疗方法是奥希替尼单药治疗。奥希替尼的剂量固定为 80mg/天，与体表面积（BSA）无关，但由于不良反应（AE），有些患者会停药或减少剂量。
我们对 98 例接受奥希替尼 80mg 初始治疗的 EGFR 突变阳性非小细胞肺癌（NSCLC）患者进行了回顾性队列研究。我们研究了 BSA 对奥希替尼疗效和安全性的影响。
使用受试者工作特征曲线估计 BSA 的截止值，确定为 1.5m。BSA<1.5 组有 44 例患者，BSA≥1.5 组有 54 例患者。两组患者 AE（≥3 级血液学毒性和≥3 级非血液学毒性）发生率无显著差异。然而，BSA<1.5 组因 AE 而减少剂量的发生率明显高于 BSA≥1.5 组（16 例与 5 例，p=0.003）。主要原因是疲劳、厌食、腹泻和肝功能异常。中位无进展生存期（PFS）无显著差异（BSA<1.5 组 16.9 个月，BSA≥1.5 组 18.1 个月，p=0.869）。
BSA 的差异影响奥希替尼的最佳剂量。然而，BSA 并不影响奥希替尼治疗的 PFS。因此，当使用奥希替尼作为 EGFR 突变型 NSCLC 患者的初始治疗时，应考虑减少剂量以控制 AE，尤其是在 BSA<1.5 组。
