Purpose Muscle atrophy is a major clinical feature of chronic obstructive pulmonary disease (COPD) and is considered a predictor of mortality in COPD patients. Recently, the cross-sectional area (CSA) of the erector spinae muscles measured by chest computed tomography (CT) scans (ESM CSA ) has been reported as a clinical parameter reflecting disease severity and future prognosis in patients with COPD. In addition, the serum creatinine (Cr)/cystatin C (CysC) ratio has been considered a quantitative marker of residual muscle mass, because serum Cr levels are affected by muscle mass, and correction by CysC counteracts the effect of renal function on serum Cr levels. The purpose of this study was to assess whether the serum Cr level corrected by serum CysC can be used as a predictive marker of pulmonary function and disease severity in patients with COPD. Patients and Methods A total of 99 patients without COPD and 201 patients with COPD, with a smoking history of more than 10 pack-years were enrolled in this study, and serum Cr and CysC levels were measured. On chest high-resolution CT images, %low attenuation area (LAA%) (≤960 Hounsfield units (HU)) and ESM CSA at the Th 12 level were identified. Results There was a significant correlation between the ESM CSA and the Cr/CysC ratio. The Cr/CysC ratio was significantly associated with forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) values, especially in former smokers. Conclusion The serum Cr/CysC ratio could be a convenient substitute for the measurement of muscle atrophy and pulmonary function testing in patients with COPD.

Background: The efficacy of rechallenge with immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC) patients has not yet been fully clarified. This study aimed to identify the clinical characteristics of patients with NSCLC who benefited from rechallenge with ICIs. Methods: We retrospectively reviewed the clinical records of 24 patients who were diagnosed with NSCLC and rechallenged with ICIs between August 2016 and July 2021.Results: Of the 24 patients included in the study, 11 were in the responder group (45.8%) and 13 in the nonresponder group (54.2%). The number of patients who used a different ICI from that used in the initial therapy was significantly higher in the responder group than in the nonresponder group (p = 0.006). Multivariate analysis identified lung metastasis and female sex as significant independent risk factors for nonresponse to rechallenge with ICIs. Compared to the nonresponder group, the duration of treatment after rechallenge with ICIs was significantly longer in the responder group (p = 0.016), and there was a trend toward longer overall survival (p = 0.059). Conclusions: Patients with lung cancer who were rechallenged with ICIs and without progressive disease after initial ICI therapy were able to continue ICI therapy for a longer period of time. This may be associated with longer survival. Patients with lung metastases and female patients are more likely to be nonresponsive to rechallenge with ICIs. Administration of a different type of ICI from that used in the initial ICI therapy may result in disease control. K E Y W O R D S immune checkpoint inhibitors, lung neoplasm, non-small-cell lung carcinoma

Background The risk of cancer treatment‐related acute exacerbation (AE) in patients with lung cancer and mild interstitial lung disease (ILD) on imaging, classified as indeterminate for usual interstitial pneumonia (UIP), has not previously been clarified. Methods We retrospectively reviewed the clinical records of 27 patients with lung cancer and ILD who were diagnosed and treated from April 2016 to March 2021. Results Among the 27 patients, 21 were classified as indeterminate for UIP and six as UIP/probable UIP; furthermore, 10 (46.6%) and three (50%) patients from each group, respectively, developed treatment‐related AEs. No significant difference was observed regarding the incidence of AEs between the two groups. However, significantly more patients in the AE group received immune checkpoint inhibitors (ICIs) compared to the non‐AE group (p = 0.021). Multivariate analysis revealed that the use of ICIs was a significant independent risk factor for treatment‐related AEs. Conclusions Lung cancer patients with mild ILD suggestive of indeterminate for UIP and UIP patterns are at an increased risk for treatment‐related AEs. Furthermore, ICI use is an independent risk factor for AEs in patients with lung cancer complicated by ILD, and ICIs should be used with great caution.

Background Pulmonary arteriovenous malformations are mostly caused by congenitally abnormal shunts between pulmonary arteries and pulmonary veins. Case presentation A 74-year-old Japanese woman with a history of bronchiectasis was admitted to our hospital because of dyspnea on exertion. Pulmonary angiography and reconstructed three-dimensional contrast-enhanced computed tomography images showed shunts between pulmonary arteries and pulmonary veins, indicating a diagnosis of pulmonary arteriovenous malformations. Coil embolization of the shunts was successful. Conclusions Our findings imply that bronchiectasis can cause pulmonary arteriovenous malformations, and thus patients who present with hypoxemia with bronchiectasis should be carefully evaluated.

No abstract