Department of Radiation Oncology, Maastricht University Medical Centre, The Netherlands.
Radiother Oncol. 2011 May;99(2):172-5. doi: 10.1016/j.radonc.2011.03.014. Epub 2011 May 14.
Many patients with stage I-III small cell lung cancer (SCLC) experience disease progression short after the completion of concurrent chemoradiotherapy (CRT). The purpose of the current study was to evaluate whether CT or FDG metabolic response early after the start of chemotherapy, but before the beginning of chest RT, is predictive for survival in SCLC.
Fifteen stage I-III SCLC patients treated with concurrent CRT with an FDG-PET and CT scan available before the start of chemotherapy and after or during the first cycle of chemotherapy, but before the start of radiotherapy, were selected. The metabolic volume (MV) was defined both within the primary tumour and in the involved nodal stations using the 40% (MV40) and 50% (MV50) threshold of the maximum SUV. Metabolic and CT response was assessed by the relative change in MV and CT volume, respectively, between both time points. The association between response and overall survival (OS) was analysed by univariate cox regression analysis. The minimum follow-up was 18 months.
Reductions in MV40 and MV50 were -36±38% (126.4 to 68.7cm(3)) and -44±38% (90.2 to 27.8cm(3)), respectively. The median CT volume reduction was -40±64% (190.6 to 113.8cm(3)). MV40 and MV50 changes showed a significant association with survival (HR=1.02, 95% CI: 1.00-1.04 (p=0.042); HR=1.02, 95% CI: 1.00-1.04 (p=0.048), respectively), indicating a 2% increase in survival probability for 1% reduction in metabolic volume. The CT volume change was also significantly correlated with survival (HR=1.01, 95% CI: 1.00-1.03, p=0.007).
This hypothesis generating study shows that both the early CT and the MV changes show a significant correlation with survival in SCLC. A prospective study is planned in a larger patient cohort to allow multivariate analysis, with the final aim to select patients early during treatment that could benefit from dose intensification or alternative treatment.
许多局限期 I-III 期小细胞肺癌（SCLC）患者在同步放化疗（CRT）完成后不久即出现疾病进展。本研究旨在评估在开始胸部放疗前，化疗开始后但在第一周期化疗期间或之后，进行 CT 或 FDG 代谢反应是否对 SCLC 的生存具有预测价值。
选择了 15 例接受同步 CRT 治疗且在化疗前、化疗第一周期期间或之后但在放疗开始前进行了 FDG-PET 和 CT 扫描的局限期 I-III SCLC 患者。使用最大标准摄取值（SUV）的 40%（MV40）和 50%（MV50）阈值，在原发肿瘤和受累淋巴结站内部定义代谢体积（MV）。通过两次时间点之间的 MV 和 CT 体积的相对变化来评估代谢和 CT 反应。采用单因素 COX 回归分析来分析反应与总生存期（OS）之间的关联。最小随访时间为 18 个月。
MV40 和 MV50 的减少分别为 -36±38%（126.4 至 68.7cm³）和 -44±38%（90.2 至 27.8cm³）。CT 体积的中位数减少为 -40±64%（190.6 至 113.8cm³）。MV40 和 MV50 的变化与生存显著相关（HR=1.02，95%CI：1.00-1.04（p=0.042）；HR=1.02，95%CI：1.00-1.04（p=0.048）），表明代谢体积每减少 1%，生存概率增加 2%。CT 体积的变化也与生存显著相关（HR=1.01，95%CI：1.00-1.03，p=0.007）。
这项探索性研究表明，早期 CT 和 MV 变化与 SCLC 的生存显著相关。计划在更大的患者队列中进行前瞻性研究，以允许进行多变量分析，最终目的是在治疗早期选择可能受益于剂量强化或替代治疗的患者。
