Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients’ values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.

Background: This study assessed the efficacy and safety of triple therapy with pioglitazone 15 mg add-on versus placebo in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin and dapagliflozin. Methods: In this multicenter, double-blind, randomized, phase 3 study, patients with T2DM with an inadequate response to treatment with metformin (≥1,000 mg/day) plus dapagliflozin (10 mg/day) were randomized to receive additional pioglitazone 15 mg/day (n=125) or placebo (n=125) for 24 weeks. The primary endpoint was the change in glycosylated hemoglobin (HbA1c) levels from baseline to week 24 (ClinicalTrials.gov identifier: NCT05101135). Results: At week 24, the adjusted mean change from baseline in HbA1c level compared with placebo was significantly greater with pioglitazone treatment (–0.47%; 95% confidence interval, –0.61 to –0.33; P<0.0001). A greater proportion of patients achieved HbA1c <7% or <6.5% at week 24 with pioglitazone compared to placebo as add-on to 10 mg dapagliflozin and metformin (56.8% vs. 28% for HbA1c <7%, and 23.2% vs. 9.6% for HbA1c <6.5%; P<0.0001 for all). The addition of pioglitazone also significantly improved triglyceride, highdensity lipoprotein cholesterol levels, and homeostatic model assessment of insulin resistance levels, while placebo did not. The incidence of treatment-emergent adverse events was similar between the groups, and the incidence of fluid retention-related side effects by pioglitazone was low (1.5%). Conclusion Triple therapy with the addition of 15 mg/day of pioglitazone to dapagliflozin plus metformin was well tolerated and produced significant improvements in HbA1c in patients with T2DM inadequately controlled with dapagliflozin plus metformin.

Background: Atherogenic dyslipidemia, which is frequently associated with type 2 diabetes (T2D) and insulin resistance, contributes to the development of vascular complications. Statin therapy is the primary approach to dyslipidemia management in T2D, however, the role of non-statin therapy remains unclear. Ezetimibe reduces cholesterol burden by inhibiting intestinal cholesterol absorption. Fibrates lower triglyceride levels and increase high-density lipoprotein cholesterol (HDL-C) levels via peroxisome proliferator- activated receptor alpha agonism. Therefore, when combined, these drugs effectively lower non-HDL-C levels. Despite this, few clinical trials have specifically targeted non-HDL-C, and the efficacy of triple combination therapies, including statins, ezetimibe, and fibrates, has yet to be determined. Methods: This is a multicenter, prospective, randomized, open-label, active-comparator controlled trial involving 3,958 eligible participants with T2D, cardiovascular risk factors, and elevated non-HDL-C (≥100 mg/dL). Participants, already on moderate-intensity statins, will be randomly assigned to either Ezefeno (ezetimibe/fenofibrate) addition or statin dose-escalation. The primary end point is the development of a composite of major adverse cardiovascular and diabetic microvascular events over 48 months. Conclusion This trial aims to assess whether combining statins, ezetimibe, and fenofibrate is as effective as, or possibly superior to, statin monotherapy intensification in lowering cardiovascular and microvascular disease risk for patients with T2D. This could propose a novel therapeutic approach for managing dyslipidemia in T2D.

Background: This study investigates the long-term efficacy and safety of evogliptin add-on therapy in patients with inadequately controlled type 2 diabetes mellitus (T2DM) previously received dapagliflozin and metformin (DAPA/MET) combination. Methods: In this multicenter randomized placebo-controlled phase 3 trial, patients with glycosylated hemoglobin (HbA1c) levels 7.0% to 10.5% (n=283) previously used DAPA 10 mg plus MET (≥1,000 mg) were randomly assigned to the evogliptin 5 mg once daily or placebo group (1:1). The primary endpoint was the difference in the HbA1c level from baseline at week 24, and exploratory endpoints included the efficacy and safety of evogliptin over 52 weeks (trial registration: ClinicalTrials.gov NCT04170998). Results: Evogliptin add-on to DAPA/MET therapy was superior in HbA1c reduction compared to placebo at weeks 24 and 52 (least square [LS] mean difference, –0.65% and –0.55%; 95% confidence interval [CI], –0.79 to –0.51 and –0.71 to –0.39; P<0.0001). The proportion of patients achieving HbA1c <7% was higher in the triple combination group at week 52 (32.14% vs. 8.51% in placebo; odds ratio, 5.62; P<0.0001). Evogliptin significantly reduced the fasting glucose levels and mean daily glucose levels with improvement in homeostatic model assessment of β-cell function (LS mean difference, 9.04; 95% CI, 1.86 to 16.21; P=0.0138). Adverse events were similar between the groups, and no serious adverse drug reactions were reported in the evogliptin group. Conclusion Long-term triple combination with evogliptin added to DAPA/MET showed superior HbA1c reduction and glycemic control compared to placebo at 52 weeks and was well tolerated.

Background: Enavogliflozin is a novel sodium-glucose cotransporter-2 inhibitor currently under clinical development. This study evaluated the efficacy and safety of enavogliflozin as an add-on to metformin in Korean patients with type 2 diabetes mellitus (T2DM) against dapagliflozin. Methods: In this multicenter, double-blind, randomized, phase 3 study, 200 patients were randomized to receive enavogliflozin 0.3 mg/day (n=101) or dapagliflozin 10 mg/day (n=99) in addition to ongoing metformin therapy for 24 weeks. The primary objective of the study was to prove the non-inferiority of enavogliflozin to dapagliflozin in glycosylated hemoglobin (HbA1c) change at week 24 (non-inferiority margin of 0.35%) (Clinical trial registration number: NCT04634500). Results: Adjusted mean change of HbA1c at week 24 was –0.80% with enavogliflozin and –0.75% with dapagliflozin (difference, –0.04%; 95% confidence interval, –0.21% to 0.12%). Percentages of patients achieving HbA1c <7.0% were 61% and 62%, respectively. Adjusted mean change of fasting plasma glucose at week 24 was –32.53 and –29.14 mg/dL. An increase in urine glucose-creatinine ratio (60.48 vs. 44.94, P<0.0001) and decrease in homeostasis model assessment of insulin resistance (–1.85 vs. –1.31, P=0.0041) were significantly greater with enavogliflozin than dapagliflozin at week 24. Beneficial effects of enavogliflozin on body weight (–3.77 kg vs. –3.58 kg) and blood pressure (systolic/diastolic, –5.93/–5.41 mm Hg vs. –6.57/–4.26 mm Hg) were comparable with those of dapagliflozin, and both drugs were safe and well-tolerated. Conclusion Enavogliflozin added to metformin significantly improved glycemic control in patients with T2DM and was non-inferior to dapagliflozin 10 mg, suggesting enavogliflozin as a viable treatment option for patients with inadequate glycemic control on metformin alone.

Background: This study evaluated the efficacy and safety of add-on gemigliptin in patients with type 2 diabetes mellitus (T2DM) who had inadequate glycemic control with metformin and dapagliflozin. Methods: In this randomized, placebo-controlled, parallel-group, double-blind, phase III study, 315 patients were randomized to receive either gemigliptin 50 mg (n=159) or placebo (n=156) with metformin and dapagliflozin for 24 weeks. After the 24-week treatment, patients who received the placebo were switched to gemigliptin, and all patients were treated with gemigliptin for an additional 28 weeks. Results: The baseline characteristics were similar between the two groups, except for body mass index. At week 24, the least squares mean difference (standard error) in hemoglobin A1c (HbA1c) changes was –0.66% (0.07) with a 95% confidence interval of –0.80% to –0.52%, demonstrating superior HbA1c reduction in the gemigliptin group. After week 24, the HbA1c level significantly decreased in the placebo group as gemigliptin was administered, whereas the efficacy of HbA1c reduction was maintained up to week 52 in the gemigliptin group. The safety profiles were similar: the incidence rates of treatment-emergent adverse events up to week 24 were 27.67% and 29.22% in the gemigliptin and placebo groups, respectively. The safety profiles after week 24 were similar to those up to week 24 in both groups, and no new safety findings, including hypoglycemia, were noted. Conclusion Add-on gemigliptin was well tolerated, providing comparable safety profiles and superior efficacy in glycemic control over placebo for long-term use in patients with T2DM who had poor glycemic control with metformin and dapagliflozin.

Background: Thyroid cancer mortality has been largely overlooked as relatively stable given the large gap between thyroid cancer incidence and mortality. This study evaluated long-term trends in age-standardized mortality rates (ASMRs) throughout Korea and compared them with mortality data reported by the Surveillance, Epidemiology, and End Results (SEER). Methods: Cancer-specific mortality data from 1985 to 2020 were obtained from Statistics Korea. ASMRs from thyroid cancer were calculated based on the Korean mid-year resident registration population of 2005. We assessed SEER*Explorer and downloaded the mortality data. Results: The ASMR increased from 0.19 to 0.77/100,000 between 1985 and 2002 but decreased continuously to 0.36/100,000 in 2020. The annual percent change (APC) in the ASMR between 1985 and 2003 and between 2003 and 2020 was 6.204 and −4.218, respectively, with similar patterns observed in both men and women. The ASMR of the SEER showed a modest increase from 1988 to 2016 and then stabilized. In subgroup analysis, the ASMR of the old age group (≥55 years) increased significantly from 0.82 in 1985 to 3.92/100,000 in 2002 (APC 6.917) but then decreased again to 1.86/100,000 in 2020 (APC −4.136). ASMRs according to the age group in the SEER showed a relatively stable trend even in the elderly group. Conclusion The ASMR of thyroid cancer in Korea had increased from 1985 to 2002 but has since been steadily decreasing. This trend was mainly attributed to elderly people aged 55 or over. The absolute APC value of Korea was much higher than that of the SEER.

Background: Neurogenic differentiation 1 (NeuroD1) is a representative small cell lung cancer (SCLC) transcription regulator involved in the carcinogenesis and behavior of SCLC.Histone modifications play an important role in transcription, and H3 lysine 4 trimethylation (H3K4me3) is primarily associated with promoter regions. Methods: We investigated the association between single nucleotide polymorphisms (SNPs) in NeuroD1 and H3K4me3 coincident regions, selected using ChIP sequencing (ChIP-seq), and the clinical outcomes of 261 patients with SCLC. Results: Among 230 SNPs, two were significantly associated with both the chemotherapy response and overall survival (OS) of patients with SCLC. RNF145 rs2043268A>G was associated with worse chemotherapy response and OS (under a recessive model, adjusted odds ratio [aOR], 0.50, 95% confidence interval [CI], 0.26–0.94, P = 0.031, and adjusted hazard ratio [aHR], 1.88, 95% CI, 1.38–2.57, P < 0.001). CINP rs762105A>G was also associated with worse chemotherapy response and OS (under a dominant model, aOR, 0.47, 95% CI, 0.23–0.99, P = 0.046, and aHR, 2.03, 95% CI, 1.47–2.82, P < 0.001). ChIP–quantitative polymerase chain reaction and luciferase assay confirmed that the two SNPs were located in the active promoter regions and influenced the promoter activity of each gene. Conclusion To summarize, among SNPs selected using ChIP-seq in promoter regions with high peaks in both NeuroD1 and H3K4me3, RNF145 rs2043268A>G and CINP rs762105A>G were associated with clinical outcomes in patients with SCLC and also affected the promoter activity of each gene.

Background: In this study, we evaluated the recent changes in the standardized, age-specific, stage-specific incidence rates (IRs) of thyroid cancer in Korea and compared them with the incidence data reported by the Surveillance, Epidemiology, and End Results Program. Methods: The analysis was conducted using the incidence data (2005 to 2018) from the Statistics Korea and Korea Central Cancer Registry. Results: The age-standardized IR (SIR) of thyroid cancer increased from 24.09 per 100,000 in 2005 to 74.83 in 2012 (annual percent change [APC], 14.5). From 2012 to 2015, the SIR decreased to 42.52 (APC, –17.9) and then remained stable until 2018 (APC, 2.1). This trend was similar in both men and women. Regarding age-specific IRs, the IRs for ages of 30 years and older showed a trend similar to that of the SIR; however, for ages below 30 years, no significant reduction was observed from the vertex of IR in 2015. Regarding stage-specific IRs, the increase was more prominent in those with regional disease (APC, 17.4) than in those with localized disease until 2012; then, the IR decreased until 2015 (APC, –16.1). The average APC from 2005 to 2018 increased in men, those under the age of 30 years, and those with regional disease. Conclusion The SIR in Korea peaked in 2012 and decreased until 2015 and then remained stable until 2018. However, in young individuals under the age of 30 years, the IR did not significantly decrease but tended to increase again. In terms of stage-specific IRs, the sharpest increase was seen among those with regional disease.

Background/Aims: Genome wide and candidate gene association studies have identified polymorphisms associated with the risk of lung cancer in never-smokers. This study was conducted to evaluate the association between 11 polymorphisms identified in female never smokers and the lung cancer risk in male smokers. Methods: This study included 714 lung cancer patients and 626 healthy controls. The polymorphisms were genotyped using SEQUENOM MassARRAY iPLEX assay or Taq-Man assay. Results: Two polymorphisms were associated with the risk of lung cancer in male smokers, as in female never smokers. Male smokers carrying the rs4975616 variant allele had a significantly decreased risk of lung cancer (in a codominant model: odds ratio, 0.77; 95% confidence interval, 0.61 to 0.96; p = 0.02). The rs9387478 polymorphism also reduced lung cancer risk in male smokers (in a codominant model: odds ratio, 0.85; 95% confidence interval, 0.73 to 0.997; p = 0.046). In a stratified analysis, the association between these polymorphisms and the risk of lung cancer was predominant in lighter smokers and for cases of adenocarcinoma. Conclusions These results suggest that a subset of polymorphisms known to be associated with the risk of lung cancer in female never smokers is also associated with the risk of lung cancer in male smokers.