Deep Learning Models to Predict Fatal Pneumonia Using Chest X-Ray Images.

Background and Aims: Chest X-ray (CXR) is indispensable to the assessment of severity, diagnosis, and management of pneumonia. Deep learning is an artificial intelligence (AI) technology that has been applied to the interpretation of medical images. This study investigated the feasibility of classifying fatal pneumonia based on CXR images using deep learning models on publicly available platforms. Methods: CXR images of patients with pneumonia at diagnosis were labeled as fatal or nonfatal based on medical records. We applied CXR images from 1031 patients with nonfatal pneumonia and 243 patients with fatal pneumonia for training and self-evaluation of the deep learning models. All labeled CXR images were randomly allocated to the training, validation, and test datasets of deep learning models. Data augmentation techniques were not used in this study. We created two deep learning models using two publicly available platforms. Results: The first model showed an area under the precision-recall curve of 0.929 with a sensitivity of 50.0% and a specificity of 92.4% for classifying fatal pneumonia. We evaluated the performance of our deep learning models using sensitivity, specificity, PPV, negative predictive value (NPV), accuracy, and F1 score. Using the external validation test dataset of 100 CXR images, the sensitivity, specificity, accuracy, and F1 score were 68.0%, 86.0%, 77.0%, and 74.7%, respectively. In the original dataset, the performance of the second model showed a sensitivity, specificity, and accuracy of 39.6%, 92.8%, and 82.7%, respectively, while external validation showed values of 38.0%, 92.0%, and 65.0%, respectively. The F1 score was 52.1%. These results were comparable to those obtained by respiratory physicians and residents. Conclusions: The deep learning models yielded good accuracy in classifying fatal pneumonia. By further improving the performance, AI could assist physicians in the severity assessment of patients with pneumonia.

Splenic volume in pneumococcal pneumonia patients is associated with disease severity and mortality.

Splenectomy is a risk factor for serious pneumococcal disease like overwhelming post-splenectomy infection (OPSI). In healthy individuals with small spleen, fulminant pneumococcal infection similar to OPSI has been reported. Furthermore, it is reported that small spleen was associated with severe pneumococcal infection patients treated in an intensive care unit. However, the association between the small spleen and pneumococcal pneumonia was not investigated enough. We retrospectively analyzed patients with pneumococcal pneumonia who underwent computed tomography examination with measurement of the splenic volume at Harasanshin Hospital between 2004 and 2019. Data on their background characteristics, laboratory findings, and clinical courses were collected. 413 patients were included in the final analysis. The splenic volume was significantly lower in the moderate (P < 0.001), severe (P < 0.00005), and extremely severe (P < 0.001) pneumonia groups compared with the mild pneumonia group. Furthermore, the splenic volume was significantly lower in patients died within 30 days of pneumonia treatment (median of 73.49 versus 110.77 cm3, P < 0.005) or during hospitalization (median of 71.69 versus 111.01 cm3, P < 0.0005). Splenic volume <40 cm3 was significantly associated with mortality within 30 days and total hospital mortality as a risk factor in univariate analysis. Splenic volume <40 cm3 was an independent risk factor for mortality within 30 days (odds ratio: 5.0, 95% confidence interval: 1.2-21.1, P < 0.05) and total hospital mortality (odds ratio: 7.4, 95% confidence interval: 1.8-30.6, P < 0.01) in multivariate logistic regression analysis. These results suggest that small spleen is a risk factor for severity and mortality of pneumococcal pneumonia.

Longitudinal monitoring of somatic genetic alterations in circulating cell-free DNA during treatment with epidermal growth factor receptor-tyrosine kinase inhibitors.

BACKGROUND: The aim of this study was to evaluate the potential of liquid biopsy for prediction of the efficacy of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) treatment and for assessment of the changes in genetic alterations during such treatment. METHODS: Plasma samples were prospectively collected from non-small cell lung cancer patients with EGFR-activating mutations during EGFR-TKI treatment until disease progression and were analyzed for such mutations with droplet digital polymerase chain reaction and for other somatic alterations with next-generation sequencing. RESULTS: One hundred patients, including 87 who were EGFR-TKI naïve, were enrolled. Median progression-free survival was significantly shorter for EGFR-TKI-naïve patients with EGFR-activating mutations detected in plasma at baseline than for those without them (7.9 vs 19.0 months; P < .001), with the values being significantly longer for initially positive patients who became negative for these mutations at 12 or 24 weeks than for those who remained positive. An increase in the number of alleles positive for EGFR-activating mutations in plasma during treatment was associated with disease progression, with a hazard ratio of 4.72 (95% CI, 2.07-10.79; P < .001) for EGFR-TKI-naïve patients showing an increase within 36 weeks. For 55 patients with available samples, the total number of somatic alterations (other than activating mutations or T790M of EGFR) in plasma was higher at disease progression than at baseline (33 vs 19; P = 0.04). CONCLUSION: Liquid biopsy shows potential for prediction of EGFR-TKI efficacy and elucidation of clonal tumor evolution during targeted therapy.

Retrospective cohort study on the safety and efficacy of docetaxel in Japanese non-small cell lung cancer patients with nondialysis chronic kidney disease stage 3b or higher.

BACKGROUND: It has been reported that 20% of lung cancer patients have renal impairment caused by chronic kidney disease (CKD). Since docetaxel is predominantly excreted by the hepatobiliary system, it is administered to non-small cell lung cancer (NSCLC) patients with renal impairment. However, few clinical data are available on the toxicity and efficacy of docetaxel for patients with nondialysis renal impairment. Furthermore, some cases of tubular nephrotoxicity caused by docetaxel in NSCLC patients have been reported. Therefore, a retrospective cohort study was conducted to assess the influence of nondialysis CKD on the toxicity and efficacy of docetaxel in NSCLC patients. METHODS: NSCLC patients who received docetaxel were assessed for renal function, occurrence of adverse events and treatment efficacy. RESULTS: A total of 34 NSCLC patients who received docetaxel were studied. Eight (23.5%) patients had nondialysis CKD stage 3b or higher, with an estimated glomerular filtration rate (eGFR) <45 mL/min/1.73 m2 . Although the differences were not statistically significant, the starting dose of docetaxel (mg/m2 ) was lower (60 mg/m2 ; 37.5% vs. 69.2%) in patients with an eGFR <45 than that in patients with an eGFR ≥45. No significant association was observed between pretreatment eGFR and hematological and nonhematological toxicities. No significant difference was observed in the disease control rate (62.5% vs. 65.4%, P = 1.000) or in the median overall survival (10.7 vs. 11.7, P = 0.735) between patients with an eGFR <45 and those with an eGFR ≥45. CONCLUSION: Docetaxel is a reasonable option for NSCLC patients with nondialysis CKD stage 3b or higher. Dose reduction of docetaxel is also a possibility for NSCLC patients with CKD stage 3b or higher.

Vascular endothelial growth factor promoter-based conditionally replicative adenoviruses effectively suppress growth of malignant pleural mesothelioma.

Malignant mesothelioma (MM) incidence is increasing drastically worldwide as an occupational disease resulting from asbestos exposure. However, no curative treatment for MM of advanced stage is available. Thus, new therapeutic approaches for MM are required. Because malignant pleural mesothelioma (MPM) cells spread along the pleural surface in most patients, MPM can be targeted using intrapleural therapeutic approaches. In this study, we investigated the effectiveness of the intrapleural instillation of a replication-competent adenovirus as an oncolytic agent against MPM. We constructed a vascular endothelial growth factor promoter-based conditionally replicative adenovirus (VEGF-CRAd) that replicates exclusively in VEGF-expressing cells. All of the MM cell lines that we tested expressed VEGF mRNA, and VEGF-CRAd selectively replicated in these MM cells and exerted a direct concentration-dependent oncolytic effect in vitro. Furthermore, our in vivo studies showed that pre-infection of MM cells with VEGF-CRAd potently suppressed MPM tumor formation in nude mice, and that intrapleural instillation of VEGF-CRAd prolonged the survival time of tumor-bearing mice. Our results indicate that VEGF-CRAd exerts an oncolytic effect on MM cells and that intrapleural instillation of VEGF-CRAd is safe and might represent a promising therapeutic strategy for MPM.

A new cancer cell detection method using an infectivity-enhanced adenoviral vector.

Cytological examination is widely used as a diagnostic tool because of the ease of collecting cells from the involved area. However, the diagnostic yield of cytological examination is unsatisfactory; the reasons include sampling error, poorly prepared samples, small numbers of malignant cells, and low grades of cellular atypia. In this study, we focused on the high infectivity of adenovirus towards epithelial cells and applied the luciferase- expressing adenoviral vector to a new cancer cell detection tool. In addition, adenoviral infectivity was enhanced by modifying viral fiber proteins. The sensitivity of the diagnostic tool was tested using the NCI-H1299 lung cancer cell line, and validated in body fluid samples from cancer patients with a variety of etiology. Results showed that the adenovirus efficiently transfected NCI-H1299 with high sensitivity. Only 10 cancer cells were sufficient for detection of luciferase signals. In body fluid samples, the adenovirus confirmed the diagnosis for malignant and benign cancer, but not in non-epithelial cell derived samples. This study provides proof-of-concept for a more reliable and sensitive diagnostic tool for epithelium-derived cancer.

Inhalative administration of insulin using a new bubble jet atomization device.

OBJECTIVES: In this study, we attempted to perform inhalative administration of insulin using a new "bubble jet" atomization device based on ink jet printing technology and developed by Canon Inc. The aim of this study was to confirm the usefulness of the new device for achieving a hypoglycemic effect by insulin inhalation in normal rats. METHODS: Inhaled insulin (15 U/kg) or a control solution without insulin was administrated to each Wistar rat intratracheally using the bubble-jet atomization device. Blood glucose concentrations were measured at 0, 10, 20, 30, 60, 90 and 120 min after administration of insulin or control solution. RESULTS: The blood glucose concentrations in the inhaled insulin group were 63 +/- 10 mg/dl (20 min), 43 +/- 8 mg/dl (60 min) and 35 +/- 9 mg/dl (120 min), while those in the control solution group were 80 +/- 9 mg/dl (p = 0.016), 75 +/- 10 mg/dl (p < 0.001) and 85 +/- 27 mg/dl (p < 0.001). The blood glucose concentrations after administration of inhaled insulin were significantly lower than those after administration of control solution at all time points (p < 0.05) except 0 and 10 min. CONCLUSIONS: We confirmed the hypoglycemic effect of inhaled insulin using the new bubble jet atomization device. These results proved that the new device could atomize insulin while maintaining its bioactivity.