Histological Assessment and Interobserver Agreement in Major Pathologic Response for Non-Small Cell Lung Cancer with Neoadjuvant Therapy.

Purpose: Major pathologic response (MPR), defined as ≤10% of residual viable tumor (VT), is a prognostic factor in non-small cell lung cancer (NSCLC) after neoadjuvant therapy. This study evaluated interobserver reproducibility in assessing MPR, compared area-weighted and unweighted VT (%) calculation, and determined optimal VT (%) cutoffs across histologic subtypes for survival prediction.

Materials And Methods: This retrospective study included 108 patients with NSCLC who underwent surgical resection after neoadjuvant chemotherapy or chemoradiation at Seoul National University Bundang Hospital between 2009-2018.

Artificial-Intelligence-Assisted Detection of Metastatic Colorectal Cancer Cells in Ascitic Fluid.

Ascites cytology is a cost-effective test for metastatic colorectal cancer (CRC) in the abdominal cavity. However, metastatic carcinoma of the peritoneum is difficult to diagnose based on biopsy findings, and ascitic aspiration cytology has a low sensitivity and specificity and a high inter-observer variability. The aim of the present study was to apply artificial intelligence (AI) to classify benign and malignant cells in ascites cytology patch images of metastatic CRC using a deep convolutional neural network.

Genomic Landscape of Pulmonary Sarcomatoid Carcinoma.

Purpose: Pulmonary sarcomatoid carcinoma (PSC) is a rare aggressive subtype of non-small cell lung cancer (NSCLC) with limited therapeutic strategies. We attempted to elucidate the evolutionary trajectories of PSC using multiregional and longitudinal tumor samples.

Materials And Methods: A total of 31 patients were enrolled in this study and 11 longitudinal samples were available from them.

Landscape of EGFR mutations in lung adenocarcinoma: a single institute experience with comparison of PANAMutyper testing and targeted next-generation sequencing.

Background: Activating mutations in the tyrosine kinase domain of epidermal growth factor receptor (EGFR) are predictive biomarkers for response to EGFR-tyrosine kinase inhibitor (TKI) therapy in lung adenocarcinoma (LUAD). Here, we characterized the clinicopathologic features associated with EGFR mutations via peptide nucleic acid clamping-assisted fluorescence melting curve analysis (PANAMutyper) and evaluated the feasibility of targeted deep sequencing for detecting the mutations.

Methods: We examined EGFR mutations in exons 18 through 21 for 2,088 LUADs from July 2017 to April 2020 using PANAMutyper.

Alcohol-Incorporating Diels-Alder Dimerization of Formed -Quinamine via Co-Nitrenoid Insertion.

We disclose herein a Cp*Co(III)(LX)-catalyzed dearomative Diels-Alder dimerization of 2,6-disubstituted phenyl azidoformates. Upon the postulated cobalt-nitrenoid insertion into the neighboring -carbon, the key intermediate of -quinamine was generated for the subsequent dimeric cycloaddition process. A series of experimental and computational studies suggested that the quinolinol ligand of the cobalt catalyst plays a crucial role in the alcoholic solvent incorporation into the -quinamine moiety, thereby enabling the Diels-Alder dimerization to furnish the bridged tricyclic bisamidation products.

Cobalt-Nitrenoid Insertion-Mediated Amidative Carbon Rearrangement via Alkyl-Walking on Arenes.

We herein disclose the Cp*Co(III)(LX)-catalyzed amidative alkyl migration using 2,6-disubstituted phenyl azidoformates. Upon the cobalt-nitrenoid insertion toward the substituted carbon, an arenium cationic species bearing a quaternary carbon is generated, and a subsequent alkyl migration process is suggested to occur through an unforeseen alkyl-walking mechanism. A quinolinol ligand of the cobalt catalyst system is proposed to facilitate the final product-releasing rearomatization process by serving as an internal base.

Studies of Catalyst-Controlled Regioselective Acetalization and Its Application to Single-Pot Synthesis of Differentially Protected Saccharides.

This article describes studies on the regioselective acetal protection of monosaccharide-based diols using chiral phosphoric acids (CPAs) and their immobilized polymeric variants, ()-Ad-TRIP-PS and ()-SPINOL-PS, as the catalysts. These catalyst-controlled regioselective acetalizations were found to proceed with high regioselectivities (up to >25:1 rr) on various d-glucose-, d-galactose-, d-mannose-, and l-fucose-derived 1,2-diols and could be carried out in a regiodivergent fashion depending on the choice of chiral catalyst. The polymeric catalysts were conveniently recycled and reused multiple times for gram-scale functionalizations with catalytic loadings as low as 0.

Cobalt-Catalyzed Intermolecular C-H Amidation of Unactivated Alkanes.

Alkanes are an abundant and inexpensive source of hydrocarbons; thus, development of new methods to convert the hydrocarbon feedstocks to value-added chemicals is of high interest. However, it is challenging to achieve such transformation in a direct and selective manner mainly due to the intrinsic inertness of their C-H bonds. We herein report a tailored Cp*Co(III)(LX)-catalyzed efficient and site-selective intermolecular amidation of unactivated hydrocarbons including light alkanes.

Tumor spread through air spaces (STAS): prognostic significance of grading in non-small cell lung cancer.

Tumor spread through air spaces (STAS) is an invasive pattern of lung cancer that was recently described. In this study, we investigated the association between the extent of STAS and clinicopathological characteristics and patient outcomes in resected non-small cell lung cancers (NSCLCs). STAS has been prospectively described from 2008 and graded its extent with a two-tiered system (STAS I: <2500 μm [one field of ×10 objective lens] from the edge of tumor and STAS II: ≥2500 μm from the edge of tumor) from 2011 in Seoul National University Bundang Hospital.

Versatile Cp*Co(III)(LX) Catalyst System for Selective Intramolecular C-H Amidation Reactions.

Herein, we report the development of a tailored cobalt catalyst system of Cp*Co(III)(LX) toward intramolecular C-H nitrene insertion of azidoformates to afford cyclic carbamates. The cobalt complexes were easy to prepare and bench-stable, thus offering a convenient reaction protocol. The catalytic reactivity was significantly improved by the electronic tuning of the bidentate LX ligands, and the observed regioselectivity was rationalized by the conformational analysis and DFT calculations of the transition states.

Copper(II)-Catalyzed Tandem Decarboxylative Michael/Aldol Reactions Leading to the Formation of Functionalized Cyclohexenones.

This work describes the development of a new single-pot copper(II)-catalyzed decarboxylative Michael reaction between β-keto acids and enones, followed by in situ aldolization, which results in highly functionalized chiral and achiral cyclohexenones. The achiral version of this Robinson annulation features a hitherto unprecedented Michael reaction of β-keto acids with sterically hindered β,β'-substituted enones and provides access to all carbon quaternary stereocenter-containing cyclohexenones (11 examples, 43-83% yield). In addition, an asymmetric chiral bis(oxazoline) copper(II)-catalyzed single-pot Robinson annulation has been devised for preparing chiral cyclohexenones, including some products that contain vicinal stereocenters (5 examples, 65-85% yield, 84-94% ee).

Chiral phosphoric acid-catalyzed desymmetrizative glycosylation of 2-deoxystreptamine and its application to aminoglycoside synthesis.

This work describes chiral phosphoric acid (CPA)-catalyzed desymmetrizative glycosylation of meso-diol derived from 2-deoxystreptamine. The chirality of CPA dictates the outcome of the glycosylation reactions, and the use of enantiomeric CPAs results in either C4-glycosylated (67 : 33 d.r.