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.

Purpose: The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Materials and Methods: A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire. Results: Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ. Conclusion KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.

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.

Purpose: Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH. Methods: This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups. Results: Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH. Conclusion The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.

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: Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH. Methods: This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups. Results: Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH. Conclusion The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.

Purpose: Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH. Methods: This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups. Results: Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH. Conclusion The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.

Purpose: Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH. Methods: This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups. Results: Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH. Conclusion The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.

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: Developmentally regulated GTP-binding protein 2 (DRG2) regulates microtubule dynamics and G2/M arrest during docetaxel treatment. Poly ADP-ribose polymerase (PARP) acts as an important repair system for DNA damage caused by docetaxel treatment. This study investigated whether DRG2 expression affects response to PARP inhibitors (olaparib) using prostate cancer cell lines PC3, DU145, LNCaP-FGC, and LNCaP-LN3. Materials and Methods: The cell viability and DRG2 expression levels were assessed using colorimetric-based cell viability assay and western blot. Cells were transfected with DRG2 siRNA, and pcDNA6/V5-DRG2 was used to overexpress DRG2. Flow cytometry was applied for cell cycle assay and apoptosis analysis using the Annexing V cell death assay. Results: The expression of DRG2 was highest in LNCaP-LN3 and lowest in DU145 cells. Expressions of p53 in PC3, DU145, and the two LNCaP cell lines were null-type, high-expression, and medium-expression, respectively. In PC3 (DRG2 high, p53 null) cells, docetaxel increased G2/M arrest without apoptosis; however, subsequent treatment with olaparib promoted apoptosis. In DU145 and LNCaP-FGC (DRG2 low), docetaxel increased sub-G1 but not G2/M arrest and induced apoptosis, whereas olaparib had no additional effect. In LNCaP-LN3 (DRG2 high, p53 wild-type), docetaxel increased sub-G1 and G2/M arrest, furthermore olaparib enhanced cell death. Docetaxel and olaparib combination treatment had a slight effect on DRG2 knockdown PC3, but increased apoptosis in DRG2-overexpressed DU145 cells. Conclusions DRG2 and p53 expressions play an important role in prostate cancer cell lines treated with docetaxel, and DRG2 levels can predict the response to PARP inhibitors.