Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, 651 Dongfeng Road East, Guangzhou, 510060, People's Republic of China.
Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, People's Republic of China.
Eur Radiol. 2021 Jul;31(7):5222-5233. doi: 10.1007/s00330-020-07478-1. Epub 2021 Jan 8.
The value of using PET/CT for staging of stage I-II NPC remains unclear. Hence, we aimed to investigate the survival benefit of PET/CT for staging of early-stage NPC before radical therapy.
A total of 1003 patients with pathologically confirmed NPC of stages I-II were consecutively enrolled. Among them, 218 patients underwent both PET/CT and conventional workup ([CWU], head-and-neck MRI, chest radiograph, liver ultrasound, bone scintigraphy) before treatment. The remaining 785 patients only underwent CWU. The standard of truth (SOT) for lymph node metastasis was defined by the change of size according to follow-up MRI. The diagnostic efficacies were compared in 218 patients who underwent both PET/CT and CWU. After covariate adjustment using propensity scoring, a cohort of 872 patients (218 with and 654 without pre-treatment PET/CT) was included. The primary outcome was overall survival based on intention to treat.
Retropharyngeal lymph nodes were metastatic based on follow-up MRI in 79 cases. PET/CT was significantly less sensitive than MRI in detecting retropharyngeal lymph node lesions (72.2% [62.3-82.1] vs. 91.1% [84.8-97.4], p = 0.004). Neck lymph nodes were metastatic in 89 cases and PET/CT was more sensitive than MRI (96.6% [92.8-100.0] vs. 76.4% [67.6-85.2], p < 0.001). In the survival analyses, there was no association between pre-treatment PET/CT use and improved overall survival, progression-free survival, local relapse-free survival, regional relapse-free survival, and distant metastasis-free survival.
This study showed PET/CT is of little value for staging of stage I-II NPC patients at initial imaging.
• PET/CT was more sensitive than MRI in detecting neck lymph node lesions whereas it was significantly less sensitive than MRI in detecting retropharyngeal lymph node lesions. • No association existed between pre-treatment PET/CT use and improved survival in stage I-II NPC patients.
对于 I-II 期 NPC 患者，使用 PET/CT 进行分期的价值尚不清楚。因此，我们旨在研究在根治性治疗前使用 PET/CT 对早期 NPC 分期的生存获益。
共纳入 1003 例经病理证实的 I-II 期 NPC 患者。其中 218 例患者在治疗前同时进行了 PET/CT 和常规检查（CWU，头颈部 MRI、胸部 X 线、肝脏超声、骨扫描）。其余 785 例患者仅进行 CWU。根据随访 MRI 测量的大小变化，将淋巴结转移的标准（SOT）定义为阳性。对同时行 PET/CT 和 CWU 的 218 例患者进行了诊断效能比较。通过倾向评分匹配进行协变量调整后，纳入了 872 例患者（218 例治疗前有 PET/CT，654 例无）。主要终点是基于意向治疗的总生存率。
根据随访 MRI，79 例患者出现咽后淋巴结转移。PET/CT 检测咽后淋巴结病变的灵敏度明显低于 MRI（72.2%[62.3-82.1] vs. 91.1%[84.8-97.4]，p=0.004）。89 例颈部淋巴结转移，PET/CT 比 MRI 更敏感（96.6%[92.8-100.0] vs. 76.4%[67.6-85.2]，p<0.001）。在生存分析中，治疗前使用 PET/CT 与提高总生存率、无进展生存率、局部无复发生存率、区域无复发生存率和无远处转移生存率之间均无关联。
本研究表明，在初始影像学检查中，PET/CT 对 I-II 期 NPC 患者分期的价值不大。
• PET/CT 检测颈部淋巴结病变的灵敏度高于 MRI，但检测咽后淋巴结病变的灵敏度明显低于 MRI。• 在 I-II 期 NPC 患者中，治疗前使用 PET/CT 与生存改善之间无关联。
