Background: Preclinical studies have reported anticancer properties of sodium-glucose cotransporter 2 inhibitors (SGLT2is). We aimed to elucidate the association between the use of SGLT2is and the risk of prostate cancer among male patients with type 2 diabetes mellitus (T2DM). Methods: An active-comparator, new-user cohort design using a nationwide database between September 2014 and June 2020 was conducted on 45,601 new SGLT2i users and 205,395 new users of other glucose-lowering medications (oGLMs). In the following 1:1 propensity score matched (PSM) analysis, 35,371 SGLT2i users matched with an equivalent number of oGLM users were assessed. The hazard ratios (HRs) and 95% confidence intervals (CIs) for prostate cancer were calculated. Results: Among the cohort, prostate cancer was diagnosed in 210 out of 45,601 SGLT2i users, corresponding to a cumulative incidence of 1.0%, in contrast to 1,880 cases among 205,395 users of oGLMs, with a cumulative incidence of 1.5%. The use of SGLT2is was significantly correlated with a reduced risk of prostate cancer based on a multivariable-adjusted HR of 0.83 (95% CI, 0.71 to 0.98). PSM analysis affirmed 18% reduction in prostate cancer risk associated with SGLT2i use (HR, 0.82; 95% CI, 0.67 to 0.99). Subgroup analyses revealed that body mass index (BMI) significantly influenced the effect of SGLT2i on prostate cancer risk, with a more pronounced reduction in the subgroup with a BMI <25 kg/m2 (P=0.037). Conclusion The use of SGLT2is in Korean male patients with T2DM is associated with a lower risk of prostate cancer.

OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic had direct effects on population health through infection and morbidity, as well as indirect effects on population mental health. We estimated the network structure of post-traumatic stress symptoms (PTSS) and depressive symptoms throughout the pandemic in Korea and aimed to identify the most central and bridging symptoms. METHODS: Participants aged 30–64 years completed mental health surveys across 3 phases of the COVID-19 pandemic: March 2020 (n=1,925), February–March 2021 (n=1,754), and December 2021–January 2022 (n=1,595). Using PTSS and depressive symptom data, we conducted network analyses, and the primary measures of symptom importance (centrality) were expected influence and bridge expected influence. RESULTS: In the comorbidity network, although the most central symptoms fluctuated over the course of the pandemic, sleep problems were consistently identified as the most influential bridge symptoms throughout. The symptom network structure differed between the subacute and chronic phases of the pandemic. CONCLUSIONS We found evidence of changes in the network structure of PTSS and depressive symptoms, even as sleep problems retained a consistent role as a bridging symptom. Although overall network structures varied across phases of the pandemic, the bridging role of sleep-related symptoms remained consistently strong, suggesting that sleep problems may represent a general and enduring mechanism underlying PTSS–depression comorbidity. During future pandemics, prompt screening for sleep problems may help prevent the development of comorbidity between PTSS and depressive symptoms.

Objective: To investigate the prevalence of pathological findings and clinical outcomes of riskreducing salpingo-oophorectomy (RRSO) in asymptomatic carriers with germline homologous recombination repair (HRR) gene pathogenic/likely pathogenic variants (PV/LPV). Methods: This retrospective study enrolled asymptomatic carriers with germline HR gene PV/ LPV who underwent RRSO between 2006 and 2022 at the National Cancer Center in Korea.Clinical characteristics, including history of breast cancer, family history of ovarian/breast cancer, parity, and oral contraceptive use, were analyzed. Results: Of the 255 women who underwent RRSO, 129 (50.6%) had PV/LPV in BRCA1, 121 (47.5%) in BRCA2, and 2 (0.7%) had both BRCA1 and BRCA2 PV/LPV. In addition, 1 carried PV/ LPV in RAD51D, and 2 in BRIP1. Among the BRCA1/2 PV/LPV carriers, occult neoplasms were identified in 3.5% of patients: serous tubal intraepithelial carcinoma (1.1%, n=3), fallopian tubal cancers (0.8%, n=2), ovarian cancer (1.2%, n=3), and breast cancer (0.4%, n=1). Of the 9 patients with occult neoplasms, 5 (2.0%) were identified from the 178 breast cancer patients, and 4 (1.6%) were detected in 65 healthy mutation carriers. During the median follow-up period of 36.7 months (interquartile range, 25.9–71.4), 1 (0.4%) BRCA1 PV carrier with no precursor lesions at RRSO developed primary peritoneal carcinomatosis after 30.1 months. Conclusion Women with HRR gene mutations PV/LPV who undergo RRSO are at a risk of detecting occult neoplasms, with a of 3.5%. Even in the absence of precursor lesions during RRSO, there was a cumulative risk of peritoneal carcinomatosis development, emphasizing the need for continued surveillance.

Objective: Primary frozen shoulder causes significant pain and progressively restricts shoulder movements. Diagnosis is made clinically based on patient history and physical examination. Management is mainly non-invasive owing to its self-limiting clinical course. However, clinical practice guidelines for frozen shoulder have not yet been developed in Korea. The developed guidelines aim to provide evidence-based recommendations for the diagnosis and treatment of frozen shoulder. Methods: A guideline development committee reviewed the literature from four databases (PubMed, Embase, Cochrane Library, and KMbase). Using the Population, Intervention, Comparator, and Outcome (PICO) framework, the committee formulated two backgrounds and 16 key questions to address common clinical concerns. Recommendations were made using the Grading of Recommendations, Assessment, Development, and Evaluation framework. Results: Diabetes, thyroid disease, and dyslipidemia significantly increase the risk of developing a frozen shoulder. Although frozen shoulder is often self-limiting, some patients may experience long-term functional disabilities. Ultrasound and magnetic resonance imaging should be used as adjunctive tools alongside clinical diagnosis, and rather than as independent diagnostic methods. Noninvasive approaches, such as medications, physical modalities, exercises, electrical stimulation, and manual therapy, may reduce pain and improve shoulder function. Other noninvasive interventions have limited evidence, and their application should be based on clinical judgment. Intra-articular steroid injections are recommended for treatment, and physiotherapy or hydrodilation with steroid injections can also be beneficial. Conclusion These guidelines provide evidence-based recommendations for diagnosing and treating primary frozen shoulder.

Purpose: Axillary surgery is increasingly omitted in patients with early-stage breast cancer undergoing upfront surgery, as supported by trials such as SOUND and INSEMA. However, in the neoadjuvant setting, the omission of axillary surgery has only been explored in small single-arm studies involving highly selected patients with confirmed breast pathologic complete response (pCR). The NeoNAUTILUS trial aimed to evaluate the oncologic safety of omitting sentinel lymph node biopsy (SLNB) in patients with a high probability of achieving an axillary pCR (ypN0) following neoadjuvant systemic therapy (NST), regardless of breast pCR status. Methods NeoNAUTILUS is a prospective, multicenter, randomized, controlled, noninferiority trial conducted at 12 tertiary centers in Korea. Eligible participants were women with clinical T1–T3, N0, or selected N1 invasive breast cancer, who completed NST and were candidates for breast-conserving surgery (BCS). Prior to enrollment, all patients underwent axillary ultrasound after NST completion to exclude suspicious lymph nodes. Patients with clinical N0 disease of any subtype were eligible for inclusion. Patients with clinical N1 disease with human epidermal growth factor receptor 2-positive or triple-negative tumors may be included if their primary tumor demonstrates a > 30% reduction on magnetic resonance imaging after NST. Participants were randomized 1:1 to undergo BCS with or without SLNB, stratified by clinical nodal status and tumor subtype. Patients were randomized and remained blinded until surgery. The primary endpoint is the 5-year invasive disease-free survival. A total of 464 patients are expected to be enrolled over 3 years, with a 5-year follow-up period.Discussion: NeoNAUTILUS is the first randomized trial to assess the omission of axillary surgery after NST based on the predicted nodal response, independent of breast pCR. This study may redefine axillary management in the neoadjuvant setting by identifying patients who can safely avoid SLNB, thereby reducing surgical morbidity without compromising oncologic outcomes.

Background: Primary cicatricial alopecia (PCA) is a rare disease that causes irreversible destruction of hair follicles and affects the quality of life (QOL). Objective: We aimed to investigate the disease awareness, medical use behavior, QOL, and real-world diagnosis and treatment status of patients with PCA. Methods: A self-administered questionnaire was administered to patients with PCA and their dermatologists. Patients aged between 19 and 75 years who visited one of 27 dermatology departments between September 2021 and September 2022 were included. Results: In total, 274 patients were included. The male-to-female ratio was 1:1.47, with a mean age of 45.7 years. Patients with neutrophilic and mixed PCA were predominantly male and younger than those with lymphocytic PCA. Among patients with lymphocytic PCA, lichen planopilaris was the most common type, and among those with neutrophilic PCA, folliculitis decalvans was the most common type. Among the total patients, 28.8% were previously diagnosed with PCA, 47.0% were diagnosed with PCA at least 6 months after their first hospital visit, 20.0% received early treatment within 3 months of disease onset, and 54.4% received steady treatment. More than half of the patients had a moderate to severe impairment in QOL. Topical/intralesional steroid injections were the most common treatment. Systemic immunosuppressants were frequently prescribed to patients with lymphocytic PCA, and antibiotics were mostly prescribed to patients with neutrophilic PCA. Conclusion This study provides information on the disease awareness, medical use behavior, QOL, diagnosis, and treatment status of Korean patients with PCA. This can help dermatologists educate patients with PCA to understand the necessity for early diagnosis and steady treatment.

Background: Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by tumors in multiple endocrine organs, caused by variants in the MEN1 gene. This study analyzed the clinical and genetic features of MEN1 in a Korean cohort, identifying prevalent manifestations and genetic variants, including novel variants. Methods: This multicenter retrospective study reviewed the medical records of 117 MEN1 patients treated at three tertiary centers in Korea between January 2012 and September 2022. Patient demographics, tumor manifestations, outcomes, and MEN1 genetic testing results were collected. Variants were classified using American College of Medical Genetics and Genomics (ACMG) and French Oncogenetics Network of Neuroendocrine Tumors propositions (TENGEN) guidelines. Results: A total of 117 patients were enrolled, including 55 familial cases, with a mean age at diagnosis of 37.4±15.3 years. Primary hyperparathyroidism was identified as the most common presentation (84.6%). The prevalence of gastroenteropancreatic neuroendocrine tumor and pituitary neuroendocrine tumor (PitNET) was 77.8% (n=91) and 56.4% (n=66), respectively. Genetic testing revealed 61 distinct MEN1 variants in 101 patients, with 18 being novel. Four variants were reclassified according to the TENGEN guidelines. Patients with truncating variants (n=72) exhibited a higher prevalence of PitNETs compared to those with non-truncating variants (n=25) (59.7% vs. 36.0%, P=0.040). Conclusion The association between truncating variants and an increased prevalence of PitNETs in MEN1 underscores the importance of genetic characterization in guiding the clinical management of this disease. Our study sheds light on the clinical and genetic characteristics of MEN1 among the Korean population.