Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Gastroesophageal reflux disease (GERD) is a chronic and relapsing gastrointestinal disorder characterized by the reflux of gastric contents into the esophagus, leading to troublesome symptoms and/or complications. Since the publication of the 2020 Seoul Consensus on GERD, significant new evidence has emerged, particularly regarding acid-suppressive therapies and diagnostic approaches. This 2025 focused update aims to refine GERD management strategies by incorporating the latest evidence on acid suppressive therapies and regional considerations in Asian populations. This study builds on the 2020 Seoul Consensus by integrating systematic reviews, meta-analyses, and expert consensuses to offer updated recommendations for the definition and medical treatment of GERD. These guidelines incorporate recent advances in acid-suppressive therapies, particularly potassium-competitive acid blockers, and adopt updated diagnostic frameworks in accordance with the Lyon Consensus 2.0. Key clinical questions were identified and structured using the following format: Population, Intervention, Comparator, Outcome. The resulting recommendations address the initial treatment, long-term maintenance strategies, and role of personalized therapy based on disease severity, such as the grade of reflux esophagitis. Six key statements are presented: updated definition and classification of GERD (Statement 1); initial and long-term treatment strategies tailored to GERD phenotypes, such as non-erosive reflux disease, mild erosive esophagitis, and severe erosive esophagitis (Statements 2-5); and dose optimization strategies for long-term safety (Statement 6). These guidelines aim to support gastroenterologists and general healthcare providers in making individualized evidence-based decisions for GERD management.

Background: Previous studies have shown various positive associations between the usual source of care (USC) and medication adherence in chronic diseases. However, no studies specifically on patients with diabetes have been conducted in Korea. This study examined the association between the USC type and medication adherence in patients with diabetes. Methods: Data from the 2021 Korea Health Panel Survey were used. The final sample comprised 1,493 participants aged ≥20 years. The types of USC were categorized into three groups: no USC, place only (without a regular doctor [RD]), and RD. Medication adherence was assessed using detailed items (dose, frequency, time, and discontinuation) and a four-point Likert scale. Logistic regression analysis was conducted with adjustment for control variables. Results: The odds ratios (ORs) for overall medication adherence were significantly higher in the RD group at 1.66 (95% confidence interval [CI], 1.15– 2.40) than in the no-USC group. No significant difference was observed in the place-only group at 0.73 (95% CI, 0.49–1.09). The ORs for medication adherence for each item (dosage, frequency, and timing) were also significantly higher in the RD group (2.21, 1.95, and 1.67, respectively). No statistically significant differences in these parameters were observed in the place-only group. Conclusion The presence of an RD positively affected medication adherence in patients with diabetes, but the presence of place-only did not. These findings emphasize the importance of an RD for medication adherence.

Background: Previous studies have shown various positive associations between the usual source of care (USC) and medication adherence in chronic diseases. However, no studies specifically on patients with diabetes have been conducted in Korea. This study examined the association between the USC type and medication adherence in patients with diabetes. Methods: Data from the 2021 Korea Health Panel Survey were used. The final sample comprised 1,493 participants aged ≥20 years. The types of USC were categorized into three groups: no USC, place only (without a regular doctor [RD]), and RD. Medication adherence was assessed using detailed items (dose, frequency, time, and discontinuation) and a four-point Likert scale. Logistic regression analysis was conducted with adjustment for control variables. Results: The odds ratios (ORs) for overall medication adherence were significantly higher in the RD group at 1.66 (95% confidence interval [CI], 1.15– 2.40) than in the no-USC group. No significant difference was observed in the place-only group at 0.73 (95% CI, 0.49–1.09). The ORs for medication adherence for each item (dosage, frequency, and timing) were also significantly higher in the RD group (2.21, 1.95, and 1.67, respectively). No statistically significant differences in these parameters were observed in the place-only group. Conclusion The presence of an RD positively affected medication adherence in patients with diabetes, but the presence of place-only did not. These findings emphasize the importance of an RD for medication adherence.

Background: Previous studies have shown various positive associations between the usual source of care (USC) and medication adherence in chronic diseases. However, no studies specifically on patients with diabetes have been conducted in Korea. This study examined the association between the USC type and medication adherence in patients with diabetes. Methods: Data from the 2021 Korea Health Panel Survey were used. The final sample comprised 1,493 participants aged ≥20 years. The types of USC were categorized into three groups: no USC, place only (without a regular doctor [RD]), and RD. Medication adherence was assessed using detailed items (dose, frequency, time, and discontinuation) and a four-point Likert scale. Logistic regression analysis was conducted with adjustment for control variables. Results: The odds ratios (ORs) for overall medication adherence were significantly higher in the RD group at 1.66 (95% confidence interval [CI], 1.15– 2.40) than in the no-USC group. No significant difference was observed in the place-only group at 0.73 (95% CI, 0.49–1.09). The ORs for medication adherence for each item (dosage, frequency, and timing) were also significantly higher in the RD group (2.21, 1.95, and 1.67, respectively). No statistically significant differences in these parameters were observed in the place-only group. Conclusion The presence of an RD positively affected medication adherence in patients with diabetes, but the presence of place-only did not. These findings emphasize the importance of an RD for medication adherence.

Background: Previous studies have shown various positive associations between the usual source of care (USC) and medication adherence in chronic diseases. However, no studies specifically on patients with diabetes have been conducted in Korea. This study examined the association between the USC type and medication adherence in patients with diabetes. Methods: Data from the 2021 Korea Health Panel Survey were used. The final sample comprised 1,493 participants aged ≥20 years. The types of USC were categorized into three groups: no USC, place only (without a regular doctor [RD]), and RD. Medication adherence was assessed using detailed items (dose, frequency, time, and discontinuation) and a four-point Likert scale. Logistic regression analysis was conducted with adjustment for control variables. Results: The odds ratios (ORs) for overall medication adherence were significantly higher in the RD group at 1.66 (95% confidence interval [CI], 1.15– 2.40) than in the no-USC group. No significant difference was observed in the place-only group at 0.73 (95% CI, 0.49–1.09). The ORs for medication adherence for each item (dosage, frequency, and timing) were also significantly higher in the RD group (2.21, 1.95, and 1.67, respectively). No statistically significant differences in these parameters were observed in the place-only group. Conclusion The presence of an RD positively affected medication adherence in patients with diabetes, but the presence of place-only did not. These findings emphasize the importance of an RD for medication adherence.

Purpose: This study aimed to compare tumor tissue DNA (ttDNA) and circulating tumor DNA (ctDNA) to explore the clinical applicability of ctDNA and to better understand clonal evolution in patients with metastatic colorectal cancer undergoing palliative first-line systemic therapy. Materials and Methods: We performed targeted sequencing analysis of 88 cancer-associated genes using germline DNA, ctDNA at baseline (baseline-ctDNA), and ctDNA at progressive disease (PD-ctDNA). The results were compared with ttDNA data. Results: Among 208 consecutively enrolled patients, we selected 84 (41 males; median age, 59 years; range, 35 to 90 years) with all four sample types available. A total of 202 driver mutations were found in 34 genes. ttDNA exhibited the highest mutation frequency (n=232), followed by baseline-ctDNA (n=155) and PD-ctDNA (n=117). Sequencing ctDNA alongside ttDNA revealed additional mutations in 40 patients (47.6%). PD-ctDNA detected 13 novel mutations in 10 patients (11.9%) compared to ttDNA and baseline-ctDNA. Notably, seven mutations in five patients (6.0%) were missense or nonsense mutations in APC, TP53, SMAD4, and CDH1 genes. In baseline-ctDNA, higher maximal variant allele frequency (VAF) values (p=0.010) and higher VAF values of APC (p=0.012), TP53 (p=0.012), and KRAS (p=0.005) mutations were significantly associated with worse overall survival. Conclusion While ttDNA remains more sensitive than ctDNA, our ctDNA platform demonstrated validity and potential value when ttDNA was unavailable. Post-treatment analysis of PD-ctDNA unveiled new pathogenic mutations, signifying cancer’s clonal evolution. Additionally, baseline-ctDNA’s VAF values were prognostic after treatment.

Background: Maintaining a usual source of care (USC), which is crucial for primary healthcare, encompasses initial contact, comprehensive services, coordinated care, and ongoing support. However, limited research exists on the relationship between USC and medication adherence in patients with hypertension. This study aimed to investigate the association between USC and medication adherence among patients with hypertension. Methods: Data from the 2nd Korea Health Panel Survey 2020 were analyzed. The final sample consisted of 3,318 participants aged 19 years or older diagnosed with hypertension. USC was categorized into three groups: no USC, place only (without a regular doctor), and regular doctor. Medication adherence was assessed using detailed items (dose, frequency, time, no stop) and a 4-point Likert scale. A logistic regression analysis was conducted with control for relevant variables. Results: Compared to the no USC group, the regular doctor group had significantly higher odds ratios (ORs) for overall perfect/high medication adherence rates: 1.70 (95% confidence interval [CI], 1.42–2.03) and 1.59 (95% CI, 1.14–2.20). Similar results were observed for each adherence item, including prefect dose (OR, 2.14; 95% CI, 1.73– 2.63), frequency (OR, 1.87; 95% CI, 1.53–2.28), time (OR, 1.72; 95% CI, 1.43–2.07), and no stop (OR, 1.56; 95% CI, 1.09–2.23)/high frequency (OR, 2.47; 95% CI, 1.21–5.01), time (OR, 2.30; 95% CI, 1.19–4.44). However, the place only group showed no significant differences in medication adherence except for perfect adherence to dose (OR, 1.35; 95% CI, 1.06–1.71). Conclusion These findings provide evidence supporting the need for healthcare policies that encourage having a regular doctor in South Korea, which has a healthcare system with limited primary care.

Background: Current international guidelines recommend against deep sedation as it is associated with worse outcomes in the intensive care unit (ICU). However, in Korea the prevalence of deep sedation and its impact on patients in the ICU are not well known. Methods: From April 2020 to July 2021, a multicenter, prospective, longitudinal, noninterventional cohort study was performed in 20 Korean ICUs. Sedation depth extent was divided into light and deep using a mean Richmond Agitation–Sedation Scale value within the first 48 hours. Propensity score matching was used to balance covariables; the outcomes were compared between the two groups. Results: Overall, 631 patients (418 [66.2%] and 213 [33.8%] in the deep and light sedation groups, respectively) were included. Mortality rates were 14.1% and 8.4% in the deep and light sedation groups (P = 0.039), respectively. Kaplan-Meier estimates showed that time to extubation (P < 0.001), ICU length of stay (P = 0.005), and death P = 0.041) differed between the groups. After adjusting for confounders, early deep sedation was only associated with delayed time to extubation (hazard ratio [HR], 0.66; 95% confidence inter val [CI], 0.55– 0.80; P < 0.001). In the matched cohort, deep sedation remained significantly associated with delayed time to extubation (HR, 0.68; 95% 0.56–0.83; P < 0.001) but was not associated with ICU length of stay (HR, 0.94; 95% CI, 0.79–1.13; P = 0.500) and in-hospital mortality (HR, 1.19; 95% CI, 0.65–2.17; P = 0.582). Conclusion In many Korean ICUs, early deep sedation was highly prevalent in mechanically ventilated patients and was associated with delayed extubation, but not prolonged ICU stay or in-hospital death.

Background: A usual source of care (USC) is related to longitudinal and personalized services, which are attributes of primary care. Patient-centered communication, an important element of patient-centered care, helps physicians understand health problems from a patient’s point of view. We analyzed the association between USC and patient-centered communication. Methods: Data from the Korea Health Panel 2018 were used in the analysis. Patient-centered communication scores were obtained by combining the four communication-related questionnaire items. Usual source of care types were categorized based on responses to two questionnaire items: no USC, a place without a regular doctor and with a regular doctor. Multiple logistic regression analysis was used to adjust for confounders. Results: Good communication rate was higher for those with a regular doctor (71.8%) than for those with no USC (61.8%) or a place only (61.5%). Those with a regular doctor had better communication (odds ratio, 1.49 for individuals with poor/moderate health, and 2.08 for those with good health) than those without a USC after adjusting for confounders. In terms of communication, no difference was observed between individuals with no USC and those with a place only. Conclusion Having a regular doctor promotes communication between patients and doctors. Good communication may be a mediator between having a regular doctor and related beneficial outcomes. Better communication by having a regular doctor, along with several other benefits identified in previous studies suggests the need for a health policy that encourages individuals to have regular doctors.