Optimal approach for diagnosing peripheral lung nodules by combining electromagnetic navigation bronchoscopy and radial probe endobronchial ultrasound.

INTRODUCTION: Electromagnetic navigation bronchoscopy (ENB) and radial probe endobronchial ultrasound (RP-EBUS) are essential bronchoscopic procedures for diagnosing peripheral lung lesions. Despite their individual advantages, the optimal circumstances for their combination remain uncertain. METHODS: This single-center retrospective study enrolled 473 patients with 529 pulmonary nodules who underwent ENB and/or RP-EBUS biopsies between December 2021 and December 2022. Diagnostic yield was calculated using strict, intermediate, and liberal definitions. In the strict definition, only malignant and specific benign lesions were deemed diagnostic at the time of the index procedure. The intermediate and liberal definitions included additional results from the follow-up period. RESULTS: The diagnostic yield of the strict definition was not statistically different among the three groups (ENB/Combination/RP-EBUS 63.8%/64.2%/62.6%, p = 0.944). However, the diagnostic yield was superior in the ENB + RP-EBUS group for nodules with a bronchus type II or III and a solid part <20 mm (odds ratio 1.96, 95% confidence interval 1.09-3.53, p = 0.02). In terms of complications, bleeding was significantly higher in the ENB + RP-EBUS group (ENB/Combination/RP-EBUS 3.7% /6.2/0.6%, p = 0.002), but no major adverse event was observed. CONCLUSION: The combination of ENB and RP-EBUS enhanced the diagnostic yield for nodules with bronchus type II or III and solid part <20 mm, despite a slightly elevated risk of bleeding. Careful patient selection based on nodule characteristics is important to benefit from this combined approach.

A new model using deep learning to predict recurrence after surgical resection of lung adenocarcinoma.

This study aimed to develop a deep learning (DL) model for predicting the recurrence risk of lung adenocarcinoma (LUAD) based on its histopathological features. Clinicopathological data and whole slide images from 164 LUAD cases were collected and used to train DL models with an ImageNet pre-trained efficientnet-b2 architecture, densenet201, and resnet152. The models were trained to classify each image patch into high-risk or low-risk groups, and the case-level result was determined by multiple instance learning with final FC layer's features from a model from all patches. Analysis of the clinicopathological and genetic characteristics of the model-based risk group was performed. For predicting recurrence, the model had an area under the curve score of 0.763 with 0.750, 0.633 and 0.680 of sensitivity, specificity, and accuracy in the test set, respectively. High-risk cases for recurrence predicted by the model (HR group) were significantly associated with shorter recurrence-free survival and a higher stage (both, p < 0.001). The HR group was associated with specific histopathological features such as poorly differentiated components, complex glandular pattern components, tumor spread through air spaces, and a higher grade. In the HR group, pleural invasion, necrosis, and lymphatic invasion were more frequent, and the size of the invasion was larger (all, p < 0.001). Several genetic mutations, including TP53 (p = 0.007) mutations, were more frequently found in the HR group. The results of stages I-II were similar to those of the general cohort. DL-based model can predict the recurrence risk of LUAD and identify the presence of the TP53 gene mutation by analyzing histopathologic features.

Comparison of Clinicopathogenomic Features and Treatment Outcomes of EGFR and HER2 Exon 20 Insertion Mutations in Non-Small Cell Lung Cancer: Single-Institution Experience.

PURPOSE: Exon 20 insertion mutations (E20ins) in epidermal growth factor receptor (EGFR) or human epidermal growth factor receptor 2 (HER2) in non-small cell lung cancer (NSCLC) patients has become more important with emergence of novel agents targeting E20ins. MATERIALS AND METHODS: Advanced/Metastatic NSCLC patients with E20ins were included. EGFR E20ins was identified by two methods, next-generation sequencing (NGS) or real-time polymerase chain reaction (PCR), while HER2 E20ins was done by NGS only. RESULTS: Between December 2013 and July 2021, E20ins were identified in 107 patients at Asan Medical Center; 67 EGFR E20ins and 40 HER2 E20ins. Out of 32 patients with EGFR E20ins who had tested both PCR and NGS, 17 were identified only through NGS and the other 15 through both tests, giving a discordance rate of 53.1%. There was no clinically significant difference in clinicopathologic features between EGFR and HER2 E20ins; both were observed more frequently in adenocarcinoma, female and never-smokers. Brain metastases were evident at diagnosis in 31.8% of EGFR E20ins and 27.5% of HER2 E20ins, respectively. Platinum-based doublets demonstrated objective response rates (ORR) of 13.3% with a median progression-free survival (PFS) of 4.2 months for EGFR E20ins and 35.3% with 4.7 months for HER2 E20ins, respectively. In contrast, novel EGFR E20ins-targeted agents exhibited an ORR of 46.2% with a median PFS of 5.4 months, while HER2-targeted agents showed an ORR of 50% with that of 7.0 months. CONCLUSION: Identification of EGFR and HER2 E20ins is more important as their targeted therapies improved outcomes. Upfront NGS test as a comprehensive molecular approach is strongly warranted.

Repurposing Metabolic Inhibitors in the Treatment of Colon Adenocarcinoma Patient-Derived Models.

The effect of agonists on AMP-activated protein kinase (AMPK), mainly metformin and phenformin, has been appreciated in the treatment of multiple types of tumors. Specifically, the antitumor activity of phenformin has been demonstrated in melanomas containing the v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) activating mutation. In this report, we elucidated the synergistic antitumor effects of biguanides with metabolism inhibitors on colon tumors. Phenformin with 2-deoxy-D-glucose (2DG) inhibited tumor cell growth in cancer cell lines, including HT29 cells harboring BRAF- and p53-mutations. Biochemical analyses showed that two chemotherapeutics exerted cooperative effects to reduce tumor growth through cell cycle arrest, apoptosis, and autophagy. The drugs demonstrated activity against phosphorylated ERK and the gain-of-function p53 mutant protein. To demonstrate tumor regressive effects in vivo, we established patient-derived models, including xenograft (PDX) and organoids (PDO). Co-treatment of biguanides with chemotherapeutics efficiently reduced the growth of patient-derived colon models in comparison to treatment with a single agent. These results strongly suggest that significant therapeutic advantages would be achieved by combining AMPK activators such as phenformin and cancer metabolic inhibitors such as 2DG.