Intrahepatic cholangiocarcinoma (CCA) is the second most common primary liver cancer after hepatocellular carcinoma (HCC). However, combined HCC-CCA is a rare malignancy exhibiting hepatocytic and cholangiocytic differentiation. For both tumors, R0 resection with regional lymph node dissection remains the only potentially curative treatment. Nevertheless, key aspects of surgical management remain controversial. In this narrative review, we synthesize contemporary evidence on the surgical management of intrahepatic CCA and combined HCC-CCA. We summarize current data on lymphadenectomy, safety, and oncologic comparability of minimally invasive vs. open surgery, and integration of liver hypertrophy techniques for major hepatectomy. We also review the emerging clinical experience with immune checkpoint inhibitor-based chemoimmunotherapy as a neoadjuvant treatment and conversion surgery for advanced disease. We highlight persisting knowledge gaps and propose practical perspectives to support individualized surgical planning for this heterogeneous disease.

Objectives: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes. Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5460 ESD cases from 5250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

Background: s/Aims: Pancreaticoduodenectomy (PD) is the standard treatment for periampullary tumors, but it is technically challenging. Evidence directly comparing open, laparoscopic, robotic, and hybrid approaches is limited. This study conducts a network meta-analysis (NMA) to compare the perioperative and oncologic outcomes of open PD (OPD), laparoscopic PD (LPD), robotic PD (RPD), and hybrid PD. Methods: We searched PubMed, EMBASE, and the Cochrane Library for studies published between January 1994 and August 2024.We included randomized controlled trials and comparative observational studies that evaluated at least two PD approaches. Perioperative outcomes were the primary endpoints, while oncologic safety served as a secondary endpoint. A random-effects NMA was performed, establishing treatment hierarchies through ranking probabilities (PROSPERO ID: CRD420250365864). Results: A total of 78 studies were included (5 randomized and 73 retrospective). RPD was associated with lower blood loss compared to OPD (mean difference [MD], –163.85 mL) and LPD (MD, –84.14 mL). Hospital stays were also shorter for RPD compared to OPD (MD, –2.50 days) and LPD (MD, –1.88 days). In contrast, OPD was the most time-efficient approach compared to LPD (MD, –77.61 minutes) and RPD (MD, –73.30 minutes). Mortality rates, severe complications, clinically relevant postoperative pancreatic fistula rates, and reoperation rates were comparable across all surgical approaches. In terms of oncologic safety, lymph node yield and R0 resection rates were similar for all modalities. Conclusions While OPD is the most time-efficient approach, RPD provides significant advantages in reducing intraoperative blood loss and shortening hospital stays compared to both LPD and OPD.

Purpose: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Materials and Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes.Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5,460 ESD cases from 5,250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

Objective: To evaluate the feasibility of streamlined radioembolization using yttrium-90 resin microspheres without lung shunt fraction (LSF) assessment in patients with intrahepatic cholangiocarcinoma (ICC). Materials and Methods: This single-center retrospective study included 23 patients with ICC who underwent radioembolization using resin microspheres (SIR-Spheres; SIRTEX, Woburn, MA, USA) without LSF measurement between April 2022 and April 2025.Eligibility criteria, based on prior institutional data, included a target tumor size less than 10 cm, absence of hepatic vein invasion and intratumoral dysmorphic vessels, and an institutional waiting time exceeding one week for macroaggregated albumin scintigraphy. All patients had at least one follow-up imaging study. Radiation activity was prescribed according to tumor location, liver function, and clinical setting, using both single-compartment and multi-compartment dosimetry under the assumptions of a 5% LSF and a tumor-to-normal (TN) ratio of 3. Post-treatment yttrium-90 PET/CT dosimetry was performed in 12 patients. Treatment-related toxicity, tumor response, and local tumor progression-free survival were analyzed. Results: The median administered activity was 1.43 GBq (interquartile range, 0.89–2.15). The median mean absorbed dose to the perfused tissue was 147 Gy, and the median tumor absorbed dose (TAD) was 339 Gy, assuming a TN ratio of 3. Posttreatment PET/CT analysis demonstrated a median TAD of 371 Gy and a median TN ratio of 4.7. No patient developed symptomatic radiation pneumonitis. Best tumor response was partial response in 52% of patients and stable disease in 48%. Local tumor progression-free survival rates at six months, one year, and two years were 95.2%, 81.1%, and 81.1%, respectively. Conclusion Streamlined radioembolization without LSF assessment appears feasible and may represent a practical alternative to conventional multi-step workflows in patients with ICC measuring less than 10 cm.

Purpose: Accumulating evidence has clarified that gut dysbiosis is involved in lung cancer development and progression. Although the relationship between tumors and gut microbiota has been extensively studied using clinical samples, no studies have examined the association between mutant epidermal growth factor receptor (EGFR)–induced lung carcinogenesis and dysbiosis in gut microbiota. Therefore, we investigated the gut microbiota profiles in stool samples from human lung-specific conditional EGFR-mutant transgenic mice during lung tumor carcinogenesis. Materials and Methods: Stool samples were collected before tamoxifen treatment (V1) and at each time point following mutant EGFR expression in lung tissue (V2) and lung tumor appearance (V3). Fecal 16S rRNA taxonomy was analyzed to assess microbial diversity, composition, and dynamic changes at each time point. Results: We found that microbiota richness and diversity were significantly elevated when tumors developed and grew in the lung. Phylogenetic analysis of the microbial community revealed that Lachnospiraceae, Ruminococcaceae, Porphyromonadaceae, Rhodospirillaceae, Odoribacteraceae, and Desulfovibrionaceae showed a significant increase at the V3 stage compared to the V1 stage at the family level. In contrast, Lactobacillaceae, Bacteroidaceae, Muribaculaceae, Coriobacteriaceae, and Rikenellaceae significantly decreased at the V3 stage compared to the V1 stage. Furthermore, Lactobacillus species, also known as short chain fatty acid-producing bacteria, were relatively abundant at the V1 stage but were depleted with the occurrence of lung tumors at the V3 stage. Conclusion Changes in gut microbiota, such as Lactobacillus species, may be a predictive factor for the emergence and progression of tumors in an animal model of lung adenocarcinoma induced by mutant EGFR.

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: Chromosomal alterations serve as diagnostic and prognostic markers in acute leukemia. Given the evolving landscape of chromosomal abnormalities in acute leukemia, we previously studied these over two periods. In this study, we investigated the frequency of these abnormalities and clinical trends in acute leukemia in Korea across three time periods. Methods: We retrospectively analyzed data from 1,787 patients with acute leukemia (319 children and 1,468 adults) diagnosed between 2006 and 2020. Conventional cytogenetics, FISH, and multiplex quantitative PCR were used for analysis. The patient groups were divided according to the following three study periods: 2006–2009 (I), 2010–2015 (II), and 2016–2020 (III). Results: Chromosomal aberrations were detected in 92% of patients. The PML::RARA translocation was the most frequent. Over the 15-yr period, chromosomal aberrations showed minimal changes, with specific fusion transcripts being common among patients.ALL was more prevalent in children than in adults and correlated significantly with the ETV6::RUNX1 and RUNX1::RUNX1T1 aberrations. The incidence of ALL increased during the three periods, with PML::RARA remaining common. Conclusions The frequency of chromosomal abnormalities in acute leukemia has changed subtly over time. Notably, the age of onset of adult AML has continuously increased. Our results may help in establishing diagnoses and clinical treatment strategies and developing various molecular diagnostic platforms.

Background: PM2.5 (particulate matter less than 2.5 μm) causes various health problems. Recent studies suggest that long-term exposure to PM2.5 may have a negative impact on vision. This study examined the effects of long-term exposure to concentrations of PM2.5 exceeding Korean standards on myopia prevalence. Methods: This study was conducted on adults aged 40–69 years. The PM2.5 concentrations were calculated as the 1–5-year moving averages based on the participants' residential areas. The relationships between the PM2.5 levels, categorized by the annual average concentration standard in Korea, and the prevalence of myopia were analyzed using binary logistic regression. The results were evaluated using the 95% confidence interval. Results: PM2.5 concentrations averaged over 1–3 years were not significantly associated with the prevalence of myopia. On the other hand, the prevalence of myopia was significantly higher in areas where the 4–5-year moving average PM2.5 levels exceeded the Korean standards. These findings suggest that long-term exposure to PM2.5 may have a detrimental effect on vision. Conclusions This study revealed the impact of long-term PM2.5 exposure on the prevalence of myopia, highlighting the importance of managing PM2.5 levels. Nevertheless, further cohort studies focusing on adults and in-depth research into the effects of long-term exposure will be necessary.

Background: Humans are exposed to mercury primarily in its highly toxic form, methyl mercury, which is known to have adverse effects on various organs and systems. The negative impact of mercury exposure on the growth, development, and mental health of children, from infancy to adolescence, is well-documented. However, there are no internationally standardized safe limits for mercury exposure. This study investigated the impact of dietary habits and higher body mass index (BMI) on blood mercury levels in adolescents. Methods: This study analyzed the data from the 4th Korean National Environmental Health Survey (KoNEHS) 2018–2020. The focus was on 825 middle and high school students aged 13–18 years, whose blood mercury levels were measured. A survey on dietary and lifestyle habits was also conducted. Blood mercury levels were categorized by geometric median values, and associations with overweight status and seafood consumption were examined using a generalized linear model. Results: The geometric mean blood mercury level for the entire sample was 1.37 μg/L, with levels of 1.31 μg/L in normal-weight individuals and 1.43 μg/L in overweight individuals, showing a statistically significant difference between the two groups. After adjusting for other variables, blood mercury levels were significantly associated with overweight status (estimate: 0.084; p = 0.018; 95% confidence interval [CI]: 0.015–0.153), consumption of large fish and tuna more than once a week (estimate: 0.18; p = 0.001; 95% CI: 0.077–0.284), and consumption of fish once a week or more (estimate: 0.147; p = 0.004; 95% CI: 0.043–0.250). Conclusions In adolescents, a higher BMI and an increased consumption of large fish, tuna, and fish were associated with higher blood mercury levels. Notably, a stronger association was found between large fish consumption and blood mercury levels in the overweight group. These findings suggest the need to moderate seafood consumption and establish more proactive mercury exposure standards for adolescents.