ObjectivesPulmonary ground-glass nodules (GGNs) are occasionally diagnosed as invasive adenocarcinomas. This study aimed to evaluate the clinicopathological features of patients with pulmonary GGNs to identify factors predictive of pathological invasion.MethodsWe retrospectively evaluated 101 pulmonary GGNs resected between July 2006 and November 2013 and pathologically classified them as adenocarcinoma in situ (AIS; n = 47), minimally invasive adenocarcinoma (MIA; n = 30), or invasive adenocarcinoma (I-ADC; n = 24). The age, sex, smoking history, tumor size, and computed tomography (CT) attenuation of the 3 groups were compared. Receiver operating characteristic (ROC) curve analyses were performed to identify factors that could predict the presence of pathologically invasive adenocarcinomas.ResultsTumor size was significantly larger in the MIA and I-ADC groups than in the AIS group. CT attenuation was significantly greater in the I-ADC group than in the AIS and MIA groups. In ROC curve analyses, the sensitivity and specificity of tumor size (cutoff, 11 mm) were 95.8% and 46.8%, respectively, and those for CT attenuation (cutoff, −680 HU) were 95.8% and 35.1%, respectively; the areas under the curve (AUC) were 0.75 and 0.77, respectively. A combination of tumor size and CT attenuation (cutoffs of 11 mm and −680 HU for tumor size and CT attenuation, respectively) yielded in a sensitivity and specificity of 91.7% and 71.4%, respectively, with an AUC of 0.82.ConclusionsTumor size and CT attenuation were predictive factors of pathological invasiveness for pulmonary GGNs. Use of a combination of tumor size and CT attenuation facilitated more accurate prediction of invasive adenocarcinoma than the use of these factors independently.

Patients over 85 years old are more likely to suffer postoperative pneumonia after gastrectomy than younger old patients. Preoperative risk assessment is essential for the oldest old patients.

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Lung cancers associated with cystic airspaces have a life-threatening risk of a missed or delayed diagnosis. Here, we report a case of pulmonary high-grade fetal adenocarcinoma, a rare lung carcinoma associated with cystic airspaces, as confirmed by computed tomography (CT) scan. A 73-year-old asymptomatic male with a 52-pack a year smoking habit was referred to our hospital. Lung CT showed a thin-walled cystic space with exophytic and endophytic solid nodules along the cyst wall. After surgery, histological analysis of a resected lung specimen revealed a pure high-grade fetal adenocarcinoma probably associated with emphysematous bullae in pulmonary emphysema, suggesting smoking contributed to this pure form, as well as the emphysema. In conclusion, when treating elderly men with a smoking history, physicians need to carefully examine the walls of cystic airspaces on CT for fetal adenocarcinoma. Key pointsSignificant findings of the study • Pulmonary high-grade fetal adenocarcinoma may be associated with emphysematous bullae manifesting as cystic air spaces as shown by computed tomography. What this study adds • When scanning by computed tomography, physicians should carefully examine the pulmonary cystic airspace walls in elderly men with a smoking history.

Background2-Deoxy-2-[fluorine-18]-fluoro-d-glucose (18F-FDG) positron emission tomography (18F-FDG-PET) is a convenient modality to assess metabolic activity within tumor cells. However, there is no consensus regarding the relationship between 18F-FDG uptake and the immune environment in thymic epithelial tumors (TETs). We conducted a clinicopathological study to elucidate the relationship between 18F-FDG uptake and programmed death ligands 1 and 2 (PD-L1/PD-L2) expression in patients with TETs. MethodsA total of 108 patients with histologically confirmed TETs classified as thymomas or thymic carcinomas who underwent surgical resection or biopsy or needle biopsy and 18F-FDG PET before any treatment between August 2007 and March 2020 were enrolled in this study. Tumor specimens underwent immunohistochemical staining for PD-L1, PD-L2, GLUT1, HIF-1α, VEGFR2, VEGF-C and β2 adrenergic receptor. ResultsHigh uptakes of SUVmax, SUVmean, MTV and TLG were identified in 28 (25.9%), 61 (56.5%), 55 (50.9%) and 55 (50.9%) of 108 patients, respectively. High uptake of SUVmax significantly correlated with PS of 1-2, thymic carcinoma and advanced stage, and SUVmax on 18F-FDG uptake displayed a close association with PD-L1 and PD-L2 expression, but not MTV and TLG. Multivariate analysis revealed that SUVmax was identified as an independent predictor for positive PD-L1 /PD-L2 expression. GLUT1 was clarified as a significant marker for the expression of PD-L1/PD-L2 from the biological viewpoint. Conclusion18F-FDG accumulation was closely associated with the expression of PD-L1/PD-L2, which, in turn, was correlated with glucose metabolism and hypoxia. PD-L1/PD-L2 could affect glucose metabolism and hypoxia in thymic tumor cells.