Although venous invasion (VI) is associated with distant metastasis and observed in >50% of pT2–4 colorectal cancers (CRCs), the role of VI in pT1 CRCs is not well-defined. Methods: Thirty-four surgically resected pT1 CRCs were reevaluated for 2-dimensional (2D) VI using hematoxylin and eosin (H&E)–stained slides with additional elastic and desmin immunohistochemical staining (cohort A). Additionally, 27 pT1 CRCs without knowing VI status were selected for 3-dimensional (3D) VI evaluation only (cohort B). All 61 cases (cohorts A and B) were studied in 3D using tissue clearing. Results: VI was detected more commonly in 3D (17/34, 50.0%) than in 2D H&E slide evaluation (9/34, 26.5%, p = .047). When VI was identified in 3D (27/61, 44.3%), the most common phase was that of intraluminal growth (22/27, 81.5%), followed by intravasation (7/27, 25.9%) and extravasation (5/27, 18.5%). E-cadherin expression was characterized in 3D in foci of VI and varied in each phase of invasion. Conclusions: All three phases were observed in VI of pT1 CRCs. The extravasation of neoplastic cells from foci of VI in pT1 CRC suggests that VI could be a route of intratumoral spreading in a subset of pT1 CRCs.

BACKGROUND/OBJECTIVES: High-protein diets are increasingly used by young women for weight loss; however, concerns have been raised regarding their potential impact on bone health under insufficient calcium intake. This study investigated the associations between highprotein diet use for weight loss and bone status and diet quality among female college students. SUBJECTS/METHODS: In total, 260 female college students residing in Chungcheong, Korea, participated in this cross-sectional study. Data were collected using questionnaires, anthropometric measurements, 24-h dietary recall, and calcaneal ultrasound assessment.Participants were classified according to self-reported weight loss attempts during the past year into non-weight control (NWC; n = 108) and weight control (WC; n = 152) groups. The WC group was further subdivided into high-protein diet (HP-WC; n = 82) and non-high-protein diet (NHP-WC; n = 70) groups on the basis of high-protein diet practices. RESULTS: The mean body weight and body mass index (BMI) were significantly greater in the WC group than in the NWC group (P < 0.001 for both). Although calcium intake was significantly lower in the HP-WC group, protein intake exceeded the recommended level more frequently in this group (P < 0.05). A dietary diversity score less than 3 was more common in the HP-WC group (P < 0.05). Osteopenia prevalence was highest in the NWC group (64.8%), followed by the HP-WC group (50.0%) and the NHP-WC group (41.4%; P < 0.05). After adjustment for BMI and other confounding factors, the bone quality index and speed of sound values were significantly lower in the HP-WC group than in the NHP-WC group. CONCLUSION These findings suggest that high-protein weight-control practices may be associated with less favorable bone parameters among female college students during early adulthood, particularly in the context of lower calcium intake and reduced dietary diversity.

Purpose: Postoperative complications following gastric cancer surgery significantly impact patient outcomes, yet standardized definitions for these events have not been consistently applied across institutions in Korea. This study aimed to develop a consensus-based, standardized complication classification system specific to gastrectomy for gastric cancer as part of the Korean Quality Improvement Platform in Surgery (K-QIPS) initiative. Methods: As part of K-QIPS, a dedicated task force team (TFT) was formed with surgical experts from fourteen high-volume hospitals across Korea. The TFT conducted ten formal meetings to review existing literature and international guidelines, and incorporated findings from randomized controlled trials. The final complication list was developed through expert consensus and structured into a standardized framework. A Data Entry Manual was created to support consistent data collection by surgical clinical reviewers. Results: The TFT defined specific postoperative complications following gastrectomy for gastric cancer, including anastomotic leakage, duodenal stump leakage, pancreatic fistula, intra-abdominal and luminal bleeding, delayed gastric emptying, and internal hernia. Notably, internal hernia was described in standardized form for the first time. General complications were developed first and overlapped in part with the gastric cancer-specific list. The task force also produced a Data Entry Manual that provides practical instructions to ensure consistency and accuracy in complication reporting. Conclusion This nationwide consensus initiative established the first standardized complication classification system for gastric cancer surgery in Korea. The proposed definitions and data entry system are expected to improve complication reporting, enable multicenter research, support surgical quality benchmarking, and ultimately enhance patient outcomes.

Purpose: Molecular characteristics of synchronous colorectal cancers (SCRCs) remain incompletely elucidated, despite their importance in targeted therapy selection. We compared the molecular characteristics and somatic mutations between SCRCs. Materials and Methods: This retrospective study (2012-2014) included 98 consecutive patients with surgically resected SCRCs. Molecular characteristics, including microsatellite instability (MSI) and tumor-infiltrating lymphocytes (TILs), were analyzed for all cancer lesions. The intertumoral heterogeneity of SCRCs was evaluated using whole-exome sequencing (WES) for 18 cancers from nine patients with at least one MSI-high (MSI-H) tumor. Results: Twelve patients had at least one MSI-H tumor; five showed discordant MSI status. Mucinous adenocarcinoma frequency and TIL density were higher in patients with at least one MSI-H tumor than in those with only microsatellite-stable tumors. WES revealed that, except one patient (6.5%), most synchronous cancers shared few variants in each patient (0.09%-0.36%). The concordance rates for BRAF, KRAS, NRAS, and PIK3CA, in synchronous cancers from each patient were 66.7%, 66.7%, 66.7%, and 55.6%, respectively. Conclusion Although synchronous cancers shared a mutated gene, the mutation subtypes differed. SCRCs exhibited 5.1% MSI status discordance rate and a high discordance rate in somatic mutational variants. As intertumoral heterogeneity may affect the targeted therapy response, molecular analysis of all tumors is recommended for patients with SCRCs.

Background: The prevalence of diabetes mellitus and early-onset dementia (EOD), defined as dementia diagnosed at an age <65 years, is increasing worldwide, with significant socioeconomic implications. We investigated the association between diabetes, prediabetes, and EOD, focusing on the influence of diabetes duration on EOD risk. Methods: Using the Korean National Health Insurance Service database, we analyzed data from 1,979,509 patients aged 40–60 years who underwent health checkups in 2009. Patients were categorized into five groups: normal, impaired fasting glucose (IFG), newly diagnosed diabetes, diabetes duration <5 years, and diabetes duration ≥5 years. Cox proportional hazard models were used to estimate the adjusted hazard ratios (aHRs) for EOD after adjusting for demographic and clinical covariates. Results: During the observation period (mean 7.75 years), 8,921 patients with EOD were identified. The diabetes group demonstrated a significantly higher incidence of EOD compared to the normal group (aHR, 1.334; 95% confidence interval [CI], 1.226 to 1.451). EOD risk increased with longer diabetes duration, with the highest risk observed in patients with diabetes ≥5 years (aHR, 1.543; 95% CI, 1.368 to 1.741). No significant difference was observed between the IFG and normal groups (aHR, 0.989; 95% CI, 0.938 to 1.043). Additionally, the hypertension group exhibited a significantly higher incidence of EOD compared to the non-hypertension group (aHR, 1.364; 95% CI, 1.291 to 1.442). Conclusion Diabetes is independently associated with increased risk of EOD, and this risk increases with longer diabetes duration. This association remained significant regardless of the presence and duration of hypertension.

Purpose: This study aimed to develop and implement an antimicrobial stewardship education program for physician assistant nurses and to evaluate its effects on their knowledge and clinical performance. Methods: A quasi-experimental, single-group pre-post design was conducted with 50 physician assistant nurses at a university hospital in Seoul, Republic of Korea. The antimicrobial stewardship education program, developed using the ADDIE model, consisted of 12 sessions including lectures and case-based learning (CBL)-based discussions.Knowledge was measured before and immediately after the intervention, while performance was assessed pre-intervention and four weeks post-program. Data were analyzed using paired t-tests, Wilcoxon signed-rank tests, and analysis of covariance (ANCOVA). Results: Knowledge scores significantly improved from 44.65±7.45 to 58.50±10.11 (p<.001), and all subdomains showed significant increases (p<.001). Performance scores increased from 3.68±0.77 to 4.28±0.68 (p<.001). Knowledge gain did not differ significantly between the medical and surgical departments (p=.710). Likewise, after adjusting for pre-test scores, no significant difference in performance improvement was observed between the two departments (ANCOVA, p=.170). These results indicate that the program was effective across both departments regardless of their characteristics. Conclusion The antimicrobial stewardship education program improved both knowledge and performance among physician assistant nurses. This program may contribute to the standardization of antimicrobial stewardship education and to appropriate antimicrobial use and the reduction of antimicrobial resistance.

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

Objective: To establish local diagnostic reference levels (DRLs) for pediatric neck CT based on age, weight, and water-equivalent diameter (WED) across multiple university hospitals in South Korea. Materials and Methods: This retrospective study analyzed pediatric neck CT examinations from nine university hospitals, involving patients aged 0–18 years. Data were categorized by age, weight, and WED, and radiation dose metrics, including volume CT dose index (CTDIvol) and dose length product, were recorded. Data retrieval and analysis were conducted using a commercially available dose-management system (Radimetrics, Bayer Healthcare). Local DRLs were established following the International Commission on Radiological Protection guidelines, using the 75th percentile as the reference value. Results: A total of 1159 CT examinations were analyzed, including 169 scans from Institution 1, 132 from Institution 2, 126 from Institution 3, 129 from Institution 4, 128 from Institution 5, 105 from Institution 6, 162 from Institution 7, 127 from Institution 8, and 81 from Institution 9. Radiation dose metrics increased with age, weight, and WED, showing significant variability both within and across institutions. For patients weighing less than 10 kg, the DRL for CTDIvol was 5.2 mGy. In the 10–19 kg group, the DRL was 5.8 mGy; in the 20–39 kg group, 7.6 mGy; in the 40–59 kg group, 11.0 mGy; and for patients weighing 60 kg or more, 16.2 mGy. DRLs for CTDIvol by age groups were as follows: 5.3 mGy for infants under 1 year, 5.7 mGy for children aged 1–4 years, 7.6 mGy for ages 5–9 years, 11.2 mGy for ages 10–14 years, and 15.6 mGy for patients 15 years or older. Conclusion Local DRLs for pediatric neck CT were established based on age, weight, and WED across nine university hospitals in South Korea.

Objective: This study aims to understand the structure of meaning in life among patients with cancer through the validation of the Meaning in Life Scale among Korean patients (K-MiLS) with cancer. Methods: From August 2021 to November 2022, participants were recruited from multiple sites in South Korea. Participants completed related questionnaires, including the MiLS, on the web or mobile. Test-retest reliability was assessed between 2 and 4 weeks after the initial assessment. Exploratory and confirmatory factor analyses and Pearson’s correlations were used to evaluate the reliability and validity of the MiLS. A multiple regression analysis was conducted to examine the sociodemographic and disease-related variables correlated with the MiLS. Regarding concurrent validity, a hierarchical regression analysis was performed. Results: The results (n=345) indicated that the K-MiLS has a four-factor structure: Harmony and Peace; Life Perspective, Purpose, and Goals; Confusion and Lessened Meaning; and Benefits of Spirituality. Regarding convergent and discriminant validity, K-MiLS was negatively correlated with Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, and Fear of Cancer Recurrence Inventory while showing a significantly positive correlation with the Posttraumatic Growth Inventory, Self-Compassion Scale, Functional Assessment of Cancer Therapy-General, and Functional Social Support Questionnaire. Hierarchical regression analysis revealed that the demographic variable influencing MiLS was religious affiliation. Conclusion The K-MiLS had a multidimensional four-factor structure similar to that of the original version. It is also a reliable and valid measure for assessing cancer survivors’ meaning in life after a cancer diagnosis.

Background: Primary cutaneous CD30+ lymphoproliferative disorders (pcCD30-LPDs) are a diseases with various clinical and prognostic characteristics. Objective: Increasing our knowledge of the clinical characteristics of pcCD30-LPDs and identifying potential prognostic variables in an Asian population. Methods: Clinicopathological features and survival data of pcCD30-LPD cases obtained from 22 hospitals in South Korea were examined. Results: A total of 413 cases of pcCD30-LPDs (lymphomatoid papulosis [LYP], n=237; primary cutaneous anaplastic large cell lymphoma [C-ALCL], n=176) were included. Ninety percent of LYP patients and roughly 50% of C-ALCL patients presented with multiple skin lesions. Both LYP and C-ALCL affected the lower limbs most frequently. Multiplicity and advanced T stage of LYP lesions were associated with a chronic course longer than 6 months. Clinical morphology with patch lesions and elevated serum lactate dehydrogenase were significantly associated with LPDs during follow-up in LYP patients. Extracutaneous involvement of C-ALCL occurred in 13.2% of patients. Lesions larger than 5 cm and increased serum lactate dehydrogenase were associated with a poor prognosis in C-ALCL. The survival of patients with C-ALCL was unaffected by the anatomical locations of skin lesions or other pathological factors. Conclusion The multiplicity or size of skin lesions was associated with a chronic course of LYP and survival among patients with C-ALCL.