Aim: To assess the role of baseline 18F-fluorodeoxyglucose ([18F]FDG)-positron emission tomography/computed tomography (PET/CT) in predicting response to immunotherapy after 6 months and overall survival (OS) in patients with lung cancer (LC) or malignant melanoma (MM). Materials and Methods: Data from a multicenter, retrospective study conducted between March and November 2021 were analyzed. Patients >18 years old with a confirmed diagnosis of LC or MM, who underwent a baseline [18F]FDG-PET/CT within 1-2 months before starting immunotherapy and had a follow-up of at least 12 months were included. PET scans were examined visually and semiquantitatively by physicians at peripheral centers. The metabolic tumor burden (number of lesions with [18F]FDG-uptake) and other parameters were recorded. Clinical response was assessed at 3 and 6 months after starting immunotherapy, and OS was calculated as the time elapsing between the PET scan and death or latest follow-up. Results: The study concerned 177 patients with LC and 101 with MM. Baseline PET/CT was positive in primary or local recurrent lesions in 78.5% and 9.9% of cases, in local/distant lymph nodes in 71.8% and 36.6%, in distant metastases in 58.8% and 84%, respectively, in LC and in MM patients. Among patients with LC, [18F]FDG-uptake in primary/recurrent lung lesions was more often associated with no clinical response to immunotherapy after 6 months than in cases without any tracer uptake. After a mean 21 months, 46.5% of patients with LC and 37.1% with MM had died. A significant correlation emerged between the site/number of [18F]FDG foci and death among patients with LC, but not among those with MM. Conclusions: In patients with LC who are candidates for immunotherapy, baseline [18F]FDG-PET/CT can help to predict response to this therapy after 6 months, and to identify those with a poor prognosis based on their metabolic parameters. For patients with MM, there was only a weak correlation between baseline PET/CT parameters, response to therapy, and survival.

中文翻译：

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基线 [18F]FDG PET/CT 能否预测肺癌或恶性黑色素瘤患者 6 个月后对免疫疗法的反应和总生存期？一项多中心回顾性研究。

目的：评估基线 18F-氟脱氧葡萄糖 ([18F]FDG)-正电子发射断层扫描/计算机断层扫描 (PET/CT) 在预测肺癌 (LC) 患者 6 个月后免疫治疗反应和总生存期 (OS) 中的作用) 或恶性黑色素瘤 (MM)。材料和方法：分析了 2021 年 3 月至 2021 年 11 月期间进行的一项多中心回顾性研究的数据。年龄大于 18 岁且确诊为 LC 或 MM、在开始免疫治疗前 1-2 个月内接受基线 [18F]FDG-PET/CT 且随访至少 12 个月的患者被纳入。外围中心的医生对 PET 扫描进行了视觉和半定量检查。记录了代谢性肿瘤负荷（具有 [18F]FDG 摄取的病灶数量）和其他参数。临床反应在开始免疫治疗后 3 个月和 6 个月进行评估，OS 计算为 PET 扫描与死亡或最近一次随访之间经过的时间。结果：该研究涉及 177 名 LC 患者和 101 名 MM 患者。基线 PET/CT 在 78.5% 和 9.9% 的原发性或局部复发性病变中呈阳性，在局部/远处淋巴结中分别为 71.8% 和 36.6%，在远处转移中分别为 58.8% 和 84%，在 LC 和MM患者。在 LC 患者中，与没有任何示踪剂摄取的病例相比，原发性/复发性肺部病变的 [18F]FDG 摄取通常与 6 个月后对免疫治疗无临床反应相关。平均 21 个月后，46.5% 的 LC 患者和 37.1% 的 MM 患者死亡。[18F]FDG 病灶的部位/数量与 LC 患者的死亡之间存在显着相关性，但不是那些有MM的人。结论：对于适合免疫治疗的 LC 患者，基线 [18F]FDG-PET/CT 有助于预测 6 个月后对该疗法的反应，并根据代谢参数识别预后不良的患者。对于 MM 患者，基线 PET/CT 参数、对治疗的反应和生存之间只有微弱的相关性。