Ectopic thyroid is thyroid tissue found in places other than the anterolateral aspect of the second to fourth tracheal ring. Mediastinal ectopic thyroid is rare and only few cases have been reported. The authors experienced a case of 41-year-old female patient with an anterior neck mass. The patient had mild chest discomfort when breathing with no other symptoms. Imaging studies suggested tumor of thymic tissue origin and surgical excision was done. The mass was successfully removed and histopathologically determined to be thyroid tissue. We hereby report with a review of literature a case of ectopic thyroid found in the mediastinum, which was successfully removed by transcervical incision.

This report presents radiologic changes after clinical improvement in a patient with acute interstitial nephritis (AIN). A 45-year-old female patient was referred for decreased renal function. Eight months prior, she had undergone hysterectomy and received chemotherapy. At the start of chemotherapy, her baseline creatinine level was 0.55 mg/dL, which rose to 1.46 mg/dL. Multiple imaging modalities performed when decreased renal function was observed revealed bilateral renal enlargement with increased cortical attenuation on computed tomography (CT), cortical hyperechogenicity on ultrasonography, and diffusion restriction in the renal cortices on magnetic resonance imaging. A renal biopsy was performed, and AIN was diagnosed. Follow-up laboratory tests showed that kidney function had improved to normal levels, and CT at that time showed a reduction in the size of both kidneys. Radiologic changes can serve as clues for the diagnosis of AIN. This is the first report to confirm radiological changes after the clinical improvement of AIN, thereby providing novel information about the course of AIN.

Objective: Previous studies have reported an association between cancer-related symptoms and perceived social support (PSS). The objective of this study was to analyze whether Chemotherapy-Induced Peripheral Neuropathy (CIPN), a prevalent side effect of chemotherapy, varies according to PSS level using a validated tool for CIPN at prospective follow-up. Methods: A total of 39 breast cancer patients were evaluated for PSS using the Multidimensional Scale of Perceived Social Support (MSPSS) prior to chemotherapy and were subsequently grouped into one of two categories for each subscale: low-to-moderate PSS and high PSS. CIPN was prospectively evaluated using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy 20 (CIPN20) at five time points. A linear mixed-effects model with square root transformation was employed to investigate whether the CIPN20 scales varied by PSS level and time point. Results: Statistical analysis of the MSPSS total scale and subscales revealed a significant effect of the friends subscale group and time point on the CIPN20 sensory scale. The sensory scale score of CIPN20 was found to be lower in participants with high PSS from friends in comparison to those with low-to-moderate PSS at 1 month post-chemotherapy (p=0.010). Conclusion This is the first study to prospectively follow the long-term effect of pre-treatment PSS from friends on CIPN. Further studies based on larger samples are required to analyze the effects of PSS on the pathophysiology of CIPN.

Purpose: The associated factors for hypertensive retinopathy (HTR) are rarely investigated. This study aimed to identify the associated factors for HTR using a systematic review. Methods: The review included cross-sectional, case-controlled, and cohort studies on HTR risk factors published in Korean and English with full texts available from PubMed, Embase, CINAHL, Web of Science, and Korean databases. Methodological quality was assessed using the Joanna Briggs Institute (JBI) checklist. Results: Eleven studies were finally selected, and three studies including patients with hypertension without diabetes mellitus, older age, male sex, alcohol consumption, the duration of hypertension, hyperglycemia, dyslipidemia, microalbuminuria, high creatinine levels, chronic kidney disease, and cardiovascular changes were identified as factors associated with HTR. Conversely, in the remaining eight studies, younger age, non-smoking status, and renal function indicators (albuminuria, high creatinine levels, chronic kidney disease, and uric acid) were identified as associated factors. Conclusions Regardless of the inclusion of patients with diabetes mellitus, impaired kidney functions were determined as significant factors associated with retinopathy in patients with HTR. However, considering a limited number of evidence and lack of evidence to confirm causality, we recommend further research on renal function and HTR.

PURPOSE: This study aimed to evaluate the accuracy of static computer-assisted implant surgery (s-CAIS) by comparing the planned and actual positions of implants placed in a partially edentulous model using surgical templates with different sleeve designs. MATERIALS AND METHODS: Forty-nine mandibular partially edentulous models were scanned using a model scanner to create standard tessellation language (STL) files. The models were divided into seven groups based on sleeve design: Group 1–4 (Open non-metal sleeves with varying heights (3 mm, 6 mm) and buccal widths (5 mm, 6 mm)), Group 5–6 (Closed non-metal sleeves with heights of 3 mm and 6 mm), and Group 7 (Closed metal sleeve). After implant placement at #45 and #47, STL files were generated and analyzed using 3D measurement software. Deviations were measured in terms of horizontal deviation (coronal and apical), vertical deviation, and angular deviation. Statistical significance was evaluated using the Wilcoxon rank sum test, Kruskal-Wallis test, and multiple generalized linear models. RESULTS: While height differences showed no significant deviations (P > .05), there was a tendency for larger apical deviation with increased sleeve height (P < .1). Closed metal and closed non-metal sleeves showed smaller deviations compared to open non-metal sleeves, except in vertical deviation. CONCLUSION Closed sleeves demonstrated greater accuracy in s-CAIS compared to open sleeves. Higher sleeves may improve implant placement accuracy, but buccal insertion width did not significantly affect accuracy.

Purpose: This study analyzed the pathological complete response (pCR) rates, long-term outcomes, and biological features of human epidermal growth factor receptor 2 (HER2)-zero, HER2-low, and HER2-positive breast cancer patients undergoing neoadjuvant treatment. Methods: This single-center study included 1,667 patients who underwent neoadjuvant chemotherapy from 2008 to 2014. Patients were categorized by HER2 status, and their clinicopathological characteristics, chemotherapy responses, and recurrence-free survival (RFS) rates were analyzed. Results: Patients with HER2-low tumors were more likely to be older (p = 0.081), have a lower histological grade (p < 0.001), and have hormone receptor (HorR)-positive tumors (p < 0.001). The HER2-positive group exhibited the highest pCR rate (23.3%), followed by the HER2-zero (15.5%) and HER2-low (10.9%) groups. However, the pCR rate did not differ between HER2-low and HER2-zero tumors in the HorR-positive or HorR-negative subgroups.The 5-year RFS rates increased in the following order: HER2-low, HER2-positive, and HER2-zero (80.0%, 77.5%, and 74.5%, respectively) (log-rank test p = 0.017). A significant survival difference between patients with HER2-low and HER2-zero tumors was only identified in HorR-negative tumors (5-year RFS for HER2-low, 74.5% vs. HER2-zero, 66.0%; log-rank test p-value = 0.04). Multivariate survival analysis revealed that achieving a pCR was the most significant factor associated with improved survival (hazard ratio [HR], 4.279; p < 0.001).Compared with HER2-zero, the HRs for HER2-low and HER2-positive tumors were 0.787 (p = 0.042) and 0.728 (p = 0.005), respectively. After excluding patients who received HER2-targeted therapy, patients with HER2-low tumors exhibited better RFS than those with HER2-zero (HR 0.784, p = 0.04), whereas those with HER2-positive tumors exhibited no significant difference compared with those with HER2-low tumors (HR, 0.975; p = 0.953). Conclusion Patients with HER2-low tumors had no significant difference in pCR rate compared to HER2-zero but showed better survival, especially in HorR-negative tumors.Further investigation into biological differences is warranted.

Purpose: This study evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer. Materials and Methods: A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery. Results: Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064). Conclusions Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.

Purpose: Claudin 18.2 (CLDN18.2) has emerged as a promising therapeutic target for CLDN18.2-expressing gastric cancer (GC). We sought to examine the heterogeneity of CLDN18.2 expression between primary GC (PGC) and metastatic GC (MGC) using various scoring methods. Materials and Methods: We retrospectively analyzed data from 102 patients with pathologically confirmed paired primary and metastatic gastric or gastroesophageal junction adenocarcinomas. CLDN18.2 expression was evaluated through immunohistochemistry on formalin-fixed paraffin-embedded tissue samples. We assessed CLDN18.2 positivity using multiple scoring approaches, including the immunoreactivity score, H-score, and the percentage of tumor cells showing moderate-to-strong staining intensity. We analyzed the concordance rates between PGC and MGC and the association of CLDN18.2 positivity with clinicopathological features. Results: CLDN18.2 positivity varied from 25% to 65% depending on the scoring method, with PGC consistently showing higher expression levels than MGC. Intratumoral heterogeneity was noted in 25.5% of PGCs and 19.6% of MGCs. Intertumoral heterogeneity, manifesting as discordance in CLDN18.2 positivity between PGC and MGC, was observed in about 20% of cases, with moderate agreement across scoring methods (κ=0.47 to 0.60).In PGC, higher CLDN18.2 positivity correlated with synchronous metastasis, presence of peritoneal metastasis, poorly differentiated grade, and biopsy specimens. In MGC, positivity was associated with synchronous metastasis, presence of peritoneal metastasis, and metastatic peritoneal tissues. Conclusions CLDN18.2 expression demonstrates significant heterogeneity between PGC and MGC, with a 20% discordance rate. Comprehensive tissue sampling and reassessment of CLDN18.2 status are crucial, especially before initiating CLDN18.2-targeted therapies.

Purpose: Since 1995, the Korean Gastric Cancer Association (KGCA) has been periodically conducting nationwide surveys on patients with surgically treated gastric cancer. This study details the results of the survey conducted in 2023. Materials and Methods: The survey was conducted from March to December 2024 using a standardized case report form. Data were collected on 86 items, including patient demographics, tumor characteristics, surgical procedures, and surgical outcomes. The results of the 2023 survey were compared with those of previous surveys. Results: Data from 12,751 cases were collected from 66 institutions. The mean patient age was 64.6 years, and the proportion of patients aged ≥71 years increased from 9.1% in 1995 to 31.7% in 2023. The proportion of upper-third tumors slightly decreased to 16.8% compared to 20.9% in 2019. Early gastric cancer accounted for 63.1% of cases in 2023.Regarding operative procedures, a totally laparoscopic approach was most frequently applied (63.2%) in 2023, while robotic gastrectomy steadily increased to 9.5% from 2.1% in 2014.The most common anastomotic method was the Billroth II procedure (48.8%) after distal gastrectomy and double-tract reconstruction (51.9%) after proximal gastrectomy in 2023.However, the proportion of esophago-gastrostomy with anti-reflux procedures increased to 30.9%. The rates of post-operative mortality and overall complications were 1.0% and 15.3%, respectively. Conclusions The results of the 2023 nationwide survey demonstrate the current status of gastric cancer treatment in Korea. This information will provide a basis for future gastric cancer research.