Visual Assessment of 18F-FDG Uptake on PET to Predict Survival Benefit to PD-1 Blockade in Non–Small Cell Lung Cancer

• Published in: Clinical nuclear medicine 2022-02, Vol.47 (2), p.108-116
• Main Authors: Hashimoto, Kosuke, Kaira, Kyoichi, Yamaguchi, Ou, Shiono, Ayako, Mouri, Atsuto, Miura, Yu, Kobayashi, Kunihiko, Imai, Hisao, Matsusaka, Yohji, Kuji, Ichiei, Kagamu, Hiroshi
• Format: Article
• Language: English
• Subjects: Carcinoma, Non-Small-Cell Lung - diagnostic imaging; Carcinoma, Non-Small-Cell Lung - drug therapy; Fluorodeoxyglucose F18; Humans; Lung Neoplasms - diagnostic imaging; Lung Neoplasms - drug therapy; Positron Emission Tomography Computed Tomography; Prognosis; Programmed Cell Death 1 Receptor - antagonists & inhibitors; Radiopharmaceuticals; Retrospective Studies
• ISSN: 0363-9762; 1536-0229
• DOI: 10.1097/RLU.0000000000004009

Programmed death 1 (PD-1) blockade is a standard treatment for patients with metastatic non-small cell lung cancer (NSCLC). Approximately 20% patients receiving PD-1 blockade monotherapy can survive for more than 5 years. However, there are limited data on the optimal biomarkers for predicting long-term outcomes. Therefore, this study aimed to evaluate the prognostic significance of 18F-FDG uptake in patients with NSCLC responding to PD-1 blockade. Thirty-eight patients with advanced NSCLC who underwent 18F-FDG PET after confirmation of clinical response to PD-1 blockade monotherapy were retrospectively included in this study. Visual assessment using a 5-point scale score according to 18F-FDG uptake was performed, and the 18F-FDG uptake cutoff score for prolonged response to PD-1 blockade was defined as 3 (low score: 1, 2, or 3 and high score: 4 or 5). A significantly greater number of patients with low scores had a performance status of 0 or 1 than patients with high scores. Among the 38 patients, 20 (53%) had a low score and 18 (47%) had a high score. Progression-free survival and overall survival were significantly longer in patients with low scores than in patients with high scores. Low 18F-FDG uptake was an independent prognostic factor for predicting favorable progression-free survival and overall survival, as confirmed by multivariate analysis. Tumors with lower 18F-FDG uptake on PET than normal hepatic lesions exhibit the possibility of prolonged response to PD-1 blockade. Visual assessment on PET is easy for every clinician and is understandable to confirm aggressive tumor activity.