PURPOSE The incidence of COVID-19 vaccine-associated hypermetabolic lymphadenopathy (VAHL) is high following the administration of the first and second BNT162b2 vaccine doses. The impact of this finding on [18F]FDG PET-CT interpretation and its correlation with the induced humoral immunity have been reported. Assuming the amnestic immune response is different following the third vaccine dose, we aimed to explore the incidence of VAHL over time after the third BNT162b2 dose administration, and its relevance to [18F]FDG PET-CT interpretation in oncologic patients. METHODS A total of 179 consecutive oncologic patients that underwent [18F]FDG PET-CT after a third BNT162b2 vaccine dose were included. The presence of VAHL was assessed. On VAHL-positive scans, the SUVmax, number, location, and size of the "hot" nodes were recorded. The median time interval between vaccination and imaging was 8 (IQR, 5-14) days. RESULTS The incidences of all-grade VAHL and grade 3-4 VAHL were 47.5% and 8.9%, respectively. VAHL was identified on 82.5% of studies performed within the first 5 days from vaccination. Grade 3-4 VAHL was observed on 28.1% of studies performed within the first 5 days from vaccination, but was not detected on studies performed more than 5 days from vaccination. Separation between VAHL and malignant lymphadenopathy was not possible in only 2 of the 179 study patients. On a multivariable logistic regression, independent predictors of grade 3-4 VAHL were short time interval between vaccination and imaging (Pv < 0.01), younger age (Pv < 0.01), and lower BMI (Pv = 0.03). CONCLUSION VAHL is commonly identified on [18F]FDG PET-CT performed within the first 5 days from the third BNT162b2 vaccine dose administration. High-grade VAHL is unlikely to be observed on a scan performed 6 days or longer from vaccination, and is even less likely in older and obese patients.

中文翻译：

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松了一口气：第三剂 COVID-19 疫苗后与疫苗相关的高代谢淋巴结病持续时间较短，并且罕见地干扰在肿瘤患者中进行的 [18F]FDG PET-CT 研究的解释。


目的 接种第一剂和第二剂 BNT162b2 疫苗后，COVID-19 疫苗相关代谢亢进性淋巴结病 (VAHL) 的发病率很高。这一发现对 [18F]FDG PET-CT 解释的影响及其与诱导体液免疫的相关性已有报道。假设第三剂疫苗接种后遗忘性免疫反应不同，我们的目的是探讨第三剂 BNT162b2 给药后一段时间内 VAHL 的发生率，及其与肿瘤患者 [18F]FDG PET-CT 解读的相关性。方法 总共纳入了 179 名在第三剂 BNT162b2 疫苗后接受 [18F]FDG PET-CT 的连续肿瘤患者。评估 VAHL 的存在。在 VAHL 阳性扫描中，记录“热”节点的 SUVmax、数量、位置和大小。疫苗接种和成像之间的中位时间间隔为 8 (IQR，5-14) 天。结果全级别VAHL和3-4级VAHL的发生率分别为47.5%和8.9%。疫苗接种后 5 天内进行的研究中有 82.5% 被鉴定为 VAHL。在疫苗接种后 5 天内进行的研究中，28.1% 观察到 3-4 级 VAHL，但在疫苗接种后 5 天以上进行的研究中未检测到。在 179 名研究患者中，只有 2 名无法区分 VAHL 和恶性淋巴结病。在多变量逻辑回归中，3-4 级 VAHL 的独立预测因素是疫苗接种和成像之间的时间间隔短 (Pv < 0.01)、年龄较小 (Pv < 0.01) 和较低的 BMI (Pv = 0.03)。结论 VAHL 通常通过在第三剂 BNT162b2 疫苗接种后的前 5 天内进行的 [18F]FDG PET-CT 来识别。 在接种疫苗后 6 天或更长时间进行的扫描中不太可能观察到高级别 VAHL，在老年和肥胖患者中更不可能观察到。