Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands.
Ann Surg. 2011 Jan;253(1):56-63. doi: 10.1097/SLA.0b013e3181f66596.
Neoadjuvant chemoradiotherapy before surgery can improve survival in patients with potentially curable esophageal cancer, but not all patients respond. Fluorodeoxyglucose positron emission tomography (FDG-PET) has been proposed to identify nonresponders early during neoadjuvant chemoradiotherapy. The aim of the present study was to determine whether FDG-PET could differentiate between responding and nonresponding esophageal tumors early in the course of neoadjuvant chemoradiotherapy.
This clinical trial comprised serial FDG-PET before and 14 days after start of chemoradiotherapy in patients with potentially curable esophageal carcinoma. Histopathologic responders were defined as patients with no or less than 10% viable tumor cells (Mandard score on resection specimen). PET response was measured using the standardized uptake value (SUV). Receiver operating characteristic analysis was used to evaluate the ability of SUV in distinguishing between histopathologic responders and nonresponders.
In 100 included patients, 64 were histopathologic responders. The median SUV decrease 14 days after the start of therapy was 30.9% for histopathologic responders and 1.7% for nonresponders (P = 0.001). In receiver operating characteristic analysis, the area under the curve was 0.71 (95% CI = 0.60-0.82). Using a 0% SUV decrease cutoff value, PET correctly identified 58 of 64 responders (sensitivity 91%) and 18 of 36 nonresponders (specificity 50%). The corresponding positive and negative predictive values were 76% and 75%, respectively.
SUV decrease 14 days after the start of chemoradiotherapy was significantly associated with histopathologic tumor response, but its accuracy in detecting nonresponders was too low to justify the clinical use of FDG-PET for early discontinuation of neoadjuvant chemoradiotherapy in patients with potentially curable esophageal cancer.
手术前的新辅助放化疗可以提高可治愈食管癌患者的生存率，但并非所有患者都有反应。氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）已被提出用于在新辅助放化疗期间早期识别无反应者。本研究旨在确定 FDG-PET 是否可以在新辅助放化疗过程中早期区分反应性和非反应性食管肿瘤。
这项临床试验包括在潜在可治愈的食管癌患者开始放化疗前和 14 天后进行的连续 FDG-PET。组织病理学反应者定义为无或少于 10%存活肿瘤细胞的患者（切除标本上的 Mandard 评分）。使用标准化摄取值（SUV）测量 PET 反应。接受者操作特征分析用于评估 SUV 区分组织病理学反应者和无反应者的能力。
在 100 名纳入的患者中，有 64 名是组织病理学反应者。治疗开始后 14 天 SUV 的中位数下降了 30.9%，对于组织病理学反应者，SUV 下降了 1.7%，对于无反应者（P = 0.001）。在接受者操作特征分析中，曲线下面积为 0.71（95%CI=0.60-0.82）。使用 0%SUV 下降截断值，PET 正确识别了 64 名反应者中的 58 名（敏感性 91%）和 36 名无反应者中的 18 名（特异性 50%）。相应的阳性和阴性预测值分别为 76%和 75%。
放化疗开始后 14 天 SUV 的下降与组织病理学肿瘤反应显著相关，但检测无反应者的准确性太低，无法证明 FDG-PET 在潜在可治愈的食管癌患者中用于早期停止新辅助放化疗的临床应用。
