Association between F-18 FDG uptake of non-cancerous lung area and acute exacerbation of interstitial pneumonia in lung cancer patients after resection

Structured Abstract Backgrounds Idiopathic pulmonary fibrosis (IPF) is defined as a specific form of progressive fibrosing interstitial pneumonia (IP). Postoperative acute exacerbation (AE) is considered a lethal comorbidity for lung cancer patients, particularly when it is accompanied with IPF. Thus, pretherapeutic risk stratification for AE has been anticipated. In this study, we aimed to investigate whether the maximum standardized uptake value (SUVmax) of F-18 fluorodeoxyglucose (FDG) is useful for assessing the postoperative risk of AE and severe respiratory adverse events (SRAEs) in lung cancer patients after surgical resection. Methods A total of 822 patients with lung cancer, who underwent preoperative high-resolution computed tomography (HRCT), FDG-positron emission tomography/CT, and pulmonary resection between July 2012 and July 2018 were assessed. SUVmax of the main tumor (Tumor-SUVmax) and that of the non-cancerous lung area (NCA-SUVmax) were measured using a three-dimensional (3D) workstation. Multivariable analyses for AE and SRAEs were performed using the logistic regression model. Results Among all patients, 120 (14.6%) patients had IPF findings on HRCT whereas SRAEs were observed in 35 (4.2%) patients, including those with AE (n = 15, 1.8%). NCA-SUVmax was independently associated with both AE and SRAEs on multivariable analysis, both in all patients and in the 120 patients with IPF. Risk stratification analysis showed that 19.0% and 30.2% of patients who were positive for IPF on HRCT and with an NCA-SUVmax > 1.69 (the optimal cut-off value relevant to AE) experienced AE and SRAEs, respectively. Conclusions NCA-SUVmax was independently associated with the incidence of postoperative AE and SRAEs in patients with lung cancer.