Purpose: The male predominance in the incidence of gastric cancer (GC) is established; however, sex differences in the prognosis of GC remain controversial. As such, this study analyzed the prognosis of patients with GC based on age and sex. Materials and Methods: Data from 14,739 patients diagnosed with GC at Seoul National University Bundang Hospital between 2003 and 2023 were analyzed. Baseline characteristics, histological types of GC, overall and GC-specific survival rates (age and stage stratification), and associated risk factors were analyzed. Results: Females were significantly younger (p < 0.001) and exhibited more gastric body cancers (p < 0.001) and tumors with diffuse-type or poorly differentiated histology (p < 0.001) than males. Females exhibited an advantage over males in terms of overall survival (p=0.004), but not in GC-specific survival. However, age stratification revealed significant sex differences, that females < 50 years of age exhibited survival disadvantages (p < 0.001); however, this trend was reversed with age, and females > 60 years exhibited survival advantages (p < 0.001) for both overall and GC-specific survival. This may be explained by the lower ratio of diffuse-type GC as females age. Furthermore, in the analysis according to stage, females with stage IV disease exhibited significant survival disadvantages, with significantly younger age and a higher proportion of diffuse-type GC which exhibits aggressive features, resulting in poorer survival than in males. Conclusion Age and stage stratification revealed significant differences in survival between the sexes, which can be helpful for public health strategies.

Background: The pulse wave transit time (PWTT) increases with decreased vascular tone resulting from sympathetic blockade caused by regional anesthesia. It oscillates, exhibiting variability due to the interaction between the autonomic nervous and cardiovascular systems. We hypothesized that interscalene brachial plexus block (ISBPB) placement increases the PWTT and reduces the low-frequency power of PWTT variability (LF). Methods: Fifty-six patients receiving an ISBPB were analyzed. The PWTT was defined as the difference in milliseconds (ms) between the R peak of the electrocardiogram and the peak of the second-derivative photoplethysmographic waveform. The LF was calculated by integrating from 0.04 to 0.15 Hz on the power spectrum obtained from fast Fourier transform. The two variables were collected during the 5 min before the end of acclimatization (baseline), between 5 and 10 min after block needle insertion, and between 15 and 20 min after block needle insertion. Results: The PWTT increased significantly (P < 0.001) from baseline (mean [SD]: 155.3 [16.7] ms) to 5–10 min post-needle insertion (166.9 [15.4] ms) (mean difference [MD]: 11.6, 95% CI [9.2–14.0], P < 0.001) and 15–20 min post-needle insertion (165.6 [16.1] ms) (MD: 10.3, 95% CI [7.3–13.2], P < 0.001). The natural log-transformed LF (lnLF) decreased significantly (P < 0.01) from baseline (1.539 [0.560] ln[ms2/Hz]) to 5–10 min post-needle insertion (1.341 [0.617] ln[ms2/Hz]) (MD: –0.198, 95% CI [–0.356 to –0.040], P < 0.01) and 15–20 min post-needle insertion (1.396 [0.548] ln[ms2/Hz]) (MD: –0.144, 95% CI [–0.274 to –0.013], P = 0.03). Conclusions The post-ISBPB decrease in lnLF and increase in PWTT may be attributable to ISBPB-induced sympathectomy.

Background/Aims: Early detection and removal of colon polyps are critical for preventing colorectal cancer. Computer-aided detection (CADe) systems have been introduced to increase the polyp detection rate (PDR) during colonoscopy, potentially enhancing its effectiveness. This study aimed to evaluate the efficacy of a CADe system in colorectal neoplasm detection. Methods: This prospective, randomized controlled trial was conducted at two tertiary centers (May 2023 to April 2025). Patients were randomly assigned to CADe or conventional colonoscopy and underwent screening, surveillance, or diagnostic colonoscopy. The primary endpoint was the adenoma detection rate (ADR), while the secondary endpoints were the PDR, relative risk (RR) of polyp detection, adenomas per colonoscopy (APC), and factors influencing adenoma detection. Results: Of 1,004 enrolled patients, 998 were randomly allocated into CADe and conventional colonoscopy groups (497 CADe system and 501 conventional colonoscopy). The CADe group had greater polyp counts (2.2 per colonoscopy vs 1.4 per colonoscopy; p<0.001) and APC values (1.2 vs 0.8; p<0.001). The CADe group showed significantly higher PDRs (72.2% vs 54.5%;p<0.001; RR, 2.173; 95% confidence interval [CI], 1.669 to 2.828) and ADRs (52.3% vs 36.1%;p<0.001; RR, 1.940; 95% CI, 1.505 to 2.499). CADe also significantly increased the detection rate of hyperplastic polyps (p=0.007; RR, 1.474; 95% CI, 1.113 to 1.952) and increased the detection rates across all sizes and locations. In multivariable analysis, CADe use was the strongest independent predictor of adenoma detection (odds ratio, 1.914; 95% CI, 1.467 to 2.496), outweighing male sex, older age, diagnostic indication, and withdrawal time. Conclusions Real-time CADe-assisted colonoscopy significantly increased PDR and ADR and proved to be a strong independent predictor of adenoma detection (cris.nih.go.kr, KCT0009664).

Background: Programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) inhibitors are effective treatments for non-small cell lung cancer (NSCLC), but their use can lead to severe pneumonitis. This study aims to evaluate the utility of Krebs von den Lungen-6 (KL-6) for predicting and diagnosing PD-1/PD-L1 inhibitor-related pneumonitis in NSCLC patients. Methods: We conducted a prospective observational study at a university-affiliated tertiary hospital in Korea from February 2022 to June 2023. Baseline KL-6 levels were measured immediately before initiating PD-1/PD-L1 inhibitor therapy. In patients who developed pneumonitis, KL-6 levels were monitored every 1–2 weeks from the onset of pneumonitis. For patients without pneumonitis, KL-6 levels were measured every 6 weeks. We compared clinical characteristics and serial KL-6 levels between the pneumonitis and non-pneumonitis groups. Results: Eighteen patients were enrolled, with 11 developing pneumonitis. Baseline KL-6 levels did not significantly differ between the two groups (261 U/mL in the pneumonitis group vs. 373 U/mL in the non-pneumonitis group, p=0.375). In the pneumonitis group, KL-6 levels generally showed an upward trend, with a median of 412 U/mL at pneumonitis onset. Conversely, KL-6 levels in the non-pneumonitis group showed no clear overall change. Conclusion In this pilot study, baseline KL-6 was not clearly linked to PD-1/PD-L1 inhibitor-related pneumonitis in NSCLC patients. However, increases in KL-6 levels post-baseline were more frequently observed in patients who developed pneumonitis, including cases of all-cause pneumonitis.

Common variable immunodeficiency (CVID) is a heterogeneous primary immunodeficiency characterized by reduced levels of immunoglobulin (Ig)G, with or without IgA and/or IgM deficiency, and hypogammaglobulinemia. Clinical manifestations are diverse, ranging from recurrent infections to autoimmune and allergic diseases. While CVID has been rarely reported in the Korean population, particularly in adults, we report 2 adult cases of CVID comorbid with asthma and Behcet’s disease. The first case of a 53-year-old with severe allergic asthma and chronic rhinosinusitis experienced recurrent respiratory infections, stomatitis, and cystitis requiring frequent antibiotic treatment. Laboratory findings indicated a T2-high asthma phenotype, with elevated serum total IgE specific IgE to dog hair and fractional exhaled nitric oxide. Immunological evaluation revealed decreased serum IgG (including IgG1 and IgG2), along with hypogammaglobulinemia. She had been treated with regular anti-IgE antibody therapy and intravenous immunoglobulin replacement therapy (IVIGRT). The second case of a 38-year-old with Behçet’s disease and uveitis had bronchial asthma and rhinitis that were exacerbated by recurrent infections despite standard asthma therapy. Laboratory findings revealed a T2-low phenotype and a marked reduction in serum IgG (including IgG1, IgG2, and IgG4), and hypogammaglobulinemia, consistent with CVID.IVIGRT effectively reduced asthma exacerbations and infection episodes in both cases. These cases highlight the clinical heterogeneity of CVID and its potential overlap with allergic and autoimmune diseases. Immunological evaluation of underlying immunodeficiency should be considered in adult patients with asthma who present with frequent exacerbations and recurrent infections. Early diagnosis and IVIGRT can prevent complications and improve outcomes.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a prevalent condition that significantly impacts quality of life and places a burden on healthcare systems. The advent of biologics targeting type 2 immune pathways offers new therapeutic options for severe and/or uncontrolled CRSwNP. Initially, biologic use was guided by the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS) 2020 and the European Forum for Research and Education in Allergy and Airway Diseases (EUFOREA) guidelines, despite limited data on clinical indications, response measures, and treatment duration. Since then, numerous studies and the EPOS/EUFOREA 2023 update have refined these guidelines. The update defines clinical indications for biologics based on type 2 inflammation markers by lowering the blood eosinophil threshold from 250 to 150 cells/μL. The response to biologics is now more simply categorized into three levels based on reductions in nasal polyp size, improvements in quality of life, and enhancement of smell. Treatment evaluation is recommended at 6 months with annual follow-up. Longer administration intervals, such as every four weeks, have also proven effective in well-controlled patients. Although specific guidelines for discontinuation or switching biologics remain lacking, clinical judgment is essential in determining when treatment should be stopped or adjusted. Additionally, regulatory updates support the use of biologics for CRSwNP, and novel agents such as tezepelumab (an anti-thymic stromal lymphopoietin monoclonal antibody) continue to show promise. Finally, in Korea, biologics for CRSwNP are not covered by national health insurance, leading to extended dosing intervals due to high costs. Despite this limitation, studies have shown that adjusted dosing can maintain subjective quality of life. Recent studies by Korean authors have also explored practical considerations such as dosing intervals and comparisons to surgery. Further research is needed to optimize treatment strategies, particularly regarding cost-effectiveness and prospective studies tailored to the Korean healthcare system.

Progesterone hypersensitivity is mediated by type I, III, and IV hypersensitivity reactions to endogenous or exogenous progesterone, involving autoimmune mechanisms in females of reproductive age. It presents with a range of dermatologic manifestations, most commonly urticaria, angioedema, eczema, and maculopapular rashes. Systemic and severe symptoms, such as generalized erythema multiforme or lesions resembling severe cutaneous adverse reactions, have rarely been reported. We describe a case of a 42-year-old woman who developed drug reaction with eosinophilia and systemic symptoms (DRESS) following exogenous progesterone therapy administered for assisted reproduction. She received high-dose subcutaneous progesterone and vaginal tablets. Despite this being her first procedure, she achieved pregnancy. However, at 8 weeks of gestation and during the third month of progesterone treatment, she developed generalized erythema multiforme, pruritus, and high-grade fever. Her laboratory findings showed increased blood eosinophil counts and inflammatory markers. After oral corticosteroid (OCS) treatment for several weeks, her skin lesions were partially improved. However, after tapering of OCS, her skin lesions were aggravated with increased blood eosinophil counts. Despite daily OCS (prednisolone, 12.5–60 mg/day) treatment after childbirth, her skin symptoms and eosinophilia persisted. Reslizumab treatment was also attempted, but only the eosinophilia resolved. These clinical findings were much improved after Janus kinase (JAK) inhibitor (upadacitinib 15 mg/day) treatment; consequently, OCS was stopped. Here, we report a case of relapsing DRESS triggered by exogenous progesterone, which has been controlled by JAK inhibitor treatment.

Progesterone hypersensitivity is mediated by type I, III, and IV hypersensitivity reactions to endogenous or exogenous progesterone, involving autoimmune mechanisms in females of reproductive age. It presents with a range of dermatologic manifestations, most commonly urticaria, angioedema, eczema, and maculopapular rashes. Systemic and severe symptoms, such as generalized erythema multiforme or lesions resembling severe cutaneous adverse reactions, have rarely been reported. We describe a case of a 42-year-old woman who developed drug reaction with eosinophilia and systemic symptoms (DRESS) following exogenous progesterone therapy administered for assisted reproduction. She received high-dose subcutaneous progesterone and vaginal tablets. Despite this being her first procedure, she achieved pregnancy. However, at 8 weeks of gestation and during the third month of progesterone treatment, she developed generalized erythema multiforme, pruritus, and high-grade fever. Her laboratory findings showed increased blood eosinophil counts and inflammatory markers. After oral corticosteroid (OCS) treatment for several weeks, her skin lesions were partially improved. However, after tapering of OCS, her skin lesions were aggravated with increased blood eosinophil counts. Despite daily OCS (prednisolone, 12.5–60 mg/day) treatment after childbirth, her skin symptoms and eosinophilia persisted. Reslizumab treatment was also attempted, but only the eosinophilia resolved. These clinical findings were much improved after Janus kinase (JAK) inhibitor (upadacitinib 15 mg/day) treatment; consequently, OCS was stopped. Here, we report a case of relapsing DRESS triggered by exogenous progesterone, which has been controlled by JAK inhibitor treatment.