Association between Tumor Size at the Time of Disease Progression and Survival Outcomes.

Purpose: This study evaluates the prognostic significance of tumor size at disease progression (PD) and depth of response (DOR) in cancer patients.

Materials And Methods: We performed post hoc analysis using data from six prospective clinical trials conducted by the Korean Cancer Study Group. Patients with tumor size at PD was categorized into 'Mild PD' and 'Significant PD' based on the cutoff values of relative change from baseline using maximally selected rank statistics.

Transcriptomic Heterogeneity of EGFR-Mutant Non-Small Cell Lung Cancer Evolution Toward Small-Cell Lung Cancer.

Purpose: Histologic transformation from EGFR-mutant non-small cell lung cancer (NSCLC) to small-cell lung cancer (SCLC) is a key mechanism of resistance to EGFR tyrosine kinase inhibitors (TKI). However, transcriptomic changes between NSCLC and transformed SCLC (t-SCLC) remain unexplored.

Experimental Design: We conducted whole-transcriptome analysis of 59 regions of interest through the spatial profiling of formalin-fixed, paraffin-embedded tissues obtained from 10 patients (lung adenocarcinoma, 22; combined SCLC/NSCLC, 7; and t-SCLC, 30 regions of interests).

The Survival and Financial Benefit of Investigator-Initiated Trials Conducted by Korean Cancer Study Group.

Purpose: The Korean Cancer Study Group (KCSG) is a nationwide cancer clinical trial group dedicated to advancing investigator-initiated trials (IITs) by conducting and supporting clinical trials. This study aims to review IITs conducted by KCSG and quantitatively evaluate the survival and financial benefits of IITs for patients.

Materials And Methods: We reviewed IITs conducted by KCSG from 1998 to 2023, analyzing progression-free survival (PFS) and overall survival (OS) gains for participants.

Resistance mechanisms of EGFR tyrosine kinase inhibitors, in EGFR exon 20 insertion-mutant lung cancer.

Background: Mobocertinib, an EGFR exon 20 insertion (Ex20ins)-specific tyrosine kinase inhibitor has been used for treatment of advanced/metastatic EGFR Ex20ins-mutant non-small cell lung cancer (NSCLC). However, resistance mechanisms to EGFR Ex20ins-specific inhibitors and the efficacy of subsequent amivantamab treatment is unknown.

Methods: To investigate resistance mechanisms, tissue and cfDNA samples were collected before treatment initiation and upon development of resistance from NSCLC patients with EGFR Ex20ins mutations received mobocertinib, poziotinib, and amivantamab treatments.

Antibiotic prescription patterns during last days of hospitalized patients with advanced cancer: the role of palliative care consultation.

Objectives: Issues regarding antibiotic use in end-of-life patients with advanced cancer present a challenging ethical dilemma in academic referral centres. This study aimed to investigate the role of palliative care consultation on antibiotic prescription patterns among hospitalized patients with advanced cancer during their last days of life.

Methods: This retrospective cohort study included adult patients with metastatic solid cancer admitted to a tertiary referral hospital for at least 4 days and subsequently died and who were given antibiotics 4 days before death between January 2018 and December 2021.

Targeting CD73 to Overcomes Resistance to First-Generation EGFR Tyrosine Kinase Inhibitors in Non-Small Cell Lung Cancer.

Purpose: In patients with epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC), EGFR tyrosine kinase inhibitors (TKIs) improve response rate and survival. However, most patients eventually develop resistance. This study aimed to identify the role of CD73 in EGFR-mutant NSCLC and explore whether CD73 inhibition may serve as a therapeutic strategy in NSCLC patients with acquired resistance to EGFR-TKIs.

Clinical outcomes after incomplete cycles of R-CHOP for diffuse large B-cell lymphoma: 10 years' real-world experience in a single institute.

Although the current standard of care for diffuse large B-cell lymphoma (DLBCL) is six cycles of rituximab/cyclophosphamide/doxorubicin/vincristine/prednisolone combination chemotherapy (R-CHOP), a larger than expected number of patients cannot complete planned six cycles for various reasons in the real world. We aimed to evaluate the prognosis of patients with DLBCL after incomplete treatment by analyzing the chemotherapy response and survival according to the cause of discontinuation and the number of cycles. We analyzed a retrospective cohort of patients diagnosed with DLBCL who underwent incomplete cycles of R-CHOP at Seoul National University Hospital and Boramae Medical Center from January 2010 to April 2019.

Monalizumab efficacy correlates with HLA-E surface expression and NK cell activity in head and neck squamous carcinoma cell lines.

Purpose: NKG2A, an inhibitory receptor expressed on NK cells and T cells, leads to immune evasion by binding to HLA-E expressed on cancer cells. Here, we investigated the relationship between HLA-E surface expression on head and neck squamous cell carcinoma (HNSCC) cell lines and the efficacy of monalizumab, an NKG2A inhibitor, in promoting NK cell activity.

Methods: Six HNSCC cell lines were used as target cells.

The antitumor activity of a novel GCN2 inhibitor in head and neck squamous cell carcinoma cell lines.

Background: General control nonderepressible 2 (GCN2) senses amino acid deprivation and activates activating transcription factor 4 (ATF4), which regulates many adaptive genes. We evaluated the impact of AST-0513, a novel GCN2 inhibitor, on the GCN2-ATF4 pathway. Additionally, we evaluated the antitumor effects of AST-0513 in amino acid deprivation in head and neck squamous cell carcinoma (HNSCC) cell lines.

Aggressiveness of care in the last days of life in the emergency department of a tertiary hospital in Korea.

Background: High-quality end-of-life (EOL) care requires both comfort care and the maintenance of dignity. However, delivering EOL in the emergency department (ED) is often challenging. Therefore, we aimed to investigate characteristics of EOL care for dying patients in the ED.

Problems Related to the Act on Decisions on Life-Sustaining Treatment and Directions for Improvement.

The Act on Decisions on Life-Sustaining Treatment has been in effect since 2018 for end-of-life patients. However, only 20~25% of deaths of terminally ill patients comply with the law, while the remaining 75~80% do not. There is significant confusion in how the law distinguishes between those in the terminal stage and those in the dying process.

Primary Prophylaxis for Pneumocystis jirovecii Pneumonia in Patients Receiving Rituximab.

Background: Although previous studies suggested that rituximab increases the risk of Pneumocystis jirovecii pneumonia (PJP), it is uncertain whether its primary prophylaxis for PJP is justified.

Research Question: Does the benefit of primary prophylaxis for PJP in patients receiving rituximab treatment outweigh the potential risk of the prophylaxis?

Study Design And Methods: This retrospective study included 3,524 patients (hematologic diseases, 2,500; rheumatic diseases, 559; pre/post-solid organ transplantation, 465) first exposed to rituximab between 2002 and 2018 in a tertiary referral center in South Korea. Patients were classified into a control group (n = 2,523) and a prophylaxis group (n = 1,001) according to the administration of prophylactic trimethoprim-sulfamethoxazole (TMP-SMX) during the first 28 days after the start of rituximab (intention-to-treat analysis).

Soluble PD-L1 is a predictive and prognostic biomarker in advanced cancer patients who receive immune checkpoint blockade treatment.

Circulating soluble programmed death-1 ligand (sPD-L1) is measurable in the serum of cancer patients. This study aimed to investigate the significance of sPD-L1 in cancer patients receiving immune checkpoint inhibitor therapy. Blood samples were obtained before and after immune checkpoint inhibitor therapy (January 2015 to January 2019).

Acquired Resistance to Third-Generation EGFR Tyrosine Kinase Inhibitors in Patients With De Novo EGFR-Mutant NSCLC.

Introduction: EGFR mostly exists subclonally and is acquired as the most common mechanism of resistance to EGFR tyrosine kinase inhibitors (TKIs). Nevertheless, because de novo EGFR-mutant NSCLC is rare, little is known on acquired resistance mechanisms to third-generation EGFR TKIs.

Methods: Acquired resistance mechanisms were analyzed using tumor and plasma samples before and after third-generation EGFR TKI treatment in four patients with de novo EGFR-mutant NSCLC.

Acquired Resistance Mechanism of EGFR Kinase Domain Duplication to EGFR TKIs in Non-Small Cell Lung Cancer.

Purpose: Epidermal growth factor receptor kinase domain duplication (EGFR-KDD) is a rare and poorly understood oncogenic mutation in non-small cell lung cancer (NSCLC). We aimed to investigate the acquired resistance mechanism of EGFR-KDD against EGFR-TKIs.

Materials And Methods: We identified EGFR-KDD in tumor tissue obtained from a patient with stage IV lung adenocarcinoma and established the patient-derived cell line SNU-4784.

Analysis of Cancer Patient Decision-Making and Health Service Utilization after Enforcement of the Life-Sustaining Treatment Decision-Making Act in Korea.

Purpose: This study aimed to confirm the decision-making patterns for life-sustaining treatment (LST) and analyze medical service utilization changes after enforcement of the Life-Sustaining Treatment Decision-Making Act.

Materials And Methods: Of 1,237 patients who completed legal forms for life-sustaining treatment (hereafter called the LST form) at three academic hospitals and died at the same institutions, 1,018 cancer patients were included. Medical service utilization and costs were analyzed using claims data.

Programmed death-ligand 1 expression level as a predictor of EGFR tyrosine kinase inhibitor efficacy in lung adenocarcinoma.

Background: The main objective of this study was to investigate the impact of programmed death-ligand 1 (PD-L1) expression on the efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) in patients with advanced non-small cell lung cancer (NSCLC).

Methods: This study analyzed 108 patients with NSCLC who had received EGFR-TKI as first-line systemic treatment at Seoul National University Bundang Hospital and Seoul National University Hospital between December 2012 and October 2018. The National Cancer Center Research Institute (NCCRI) and The Cancer Genome Atlas (TCGA) datasets were analyzed to investigate the mechanisms underlying EGFR-TKI-resistance in tumors with high PD-L1 expression.

Clinical pattern of failure after a durable response to immune check inhibitors in non-small cell lung cancer patients.

Although immune checkpoint inhibitors (ICIs) can induce durable responses in non-small-cell lung cancer (NSCLC) patients, a significant proportion of responders still experience progressive disease after a period of response. Limited data are available on the clinical patterns of acquired resistance (AR) to ICIs. Clinical and radiologic data from 125 NSCLC patients treated with anti-PD-1 or PD-L1 antibodies between 2011 and 2018 at two tertiary academic institutions were retrospectively reviewed.