Calcitonin is an important tumor marker for medullary thyroid carcinoma. Serum calcitonin is increased in most cases of medullary thyroid carcinoma. However, medullary thyroid carcinoma with normal calcitonin level has been reported very rarely. 1.2 cm sized solid thyroid nodule was suspicious for medullary thyroid carcinoma in fine needle aspiration cytology, but serum calcitonin was within the normal range. The final pathology after surgery was medullary thyroid carcinoma with positive calcitonin immunohistochemical staining. The authors present a case of calcitonin-negative medullary thyroid cancer with reviews of the mechanism, diagnosis, treatment, prognosis and follow-up of this case.

Calcitonin is an important tumor marker for medullary thyroid carcinoma. Serum calcitonin is increased in most cases of medullary thyroid carcinoma. However, medullary thyroid carcinoma with normal calcitonin level has been reported very rarely. 1.2 cm sized solid thyroid nodule was suspicious for medullary thyroid carcinoma in fine needle aspiration cytology, but serum calcitonin was within the normal range. The final pathology after surgery was medullary thyroid carcinoma with positive calcitonin immunohistochemical staining. The authors present a case of calcitonin-negative medullary thyroid cancer with reviews of the mechanism, diagnosis, treatment, prognosis and follow-up of this case.

Calcitonin is an important tumor marker for medullary thyroid carcinoma. Serum calcitonin is increased in most cases of medullary thyroid carcinoma. However, medullary thyroid carcinoma with normal calcitonin level has been reported very rarely. 1.2 cm sized solid thyroid nodule was suspicious for medullary thyroid carcinoma in fine needle aspiration cytology, but serum calcitonin was within the normal range. The final pathology after surgery was medullary thyroid carcinoma with positive calcitonin immunohistochemical staining. The authors present a case of calcitonin-negative medullary thyroid cancer with reviews of the mechanism, diagnosis, treatment, prognosis and follow-up of this case.

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: 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/Aims: Colorectal adenomas are precancerous lesions that may lead to colorectal cancer. Recent studies have shown that colorectal adenomas are associated with atherosclerosis. The cardio-ankle vascular index (CAVI) and ankle-brachial index (ABI) are noninvasive methods for evaluating atherosclerosis. This study examined the association between atherosclerosis and high-risk colorectal adenomas based on the CAVI and ABI. Methods: The data of patients aged ≥50 years who had a colonoscopy and CAVI and ABI measurements from August 2015 to December 2021 at the Kangwon National University Hospital were analyzed retrospectively. After the colonoscopy, subjects were divided into no, overall, and high-risk (size ≥1 cm, high-grade dysplasia or villous adenoma, three or more adenomas) adenoma groups based on the pathology findings. The data were subjected to univariate and multivariate logistic regression analyses. Results: Among the 1,164 subjects, adenomas and high-risk adenomas were found in 613 (52.6%) and 118 (10.1%) patients, respectively. The rate of positive ABI (<0.9) and positive CAVI (≥9.0) were significantly higher in the high-risk adenoma group (22.0% and 55.9%) than in the no adenoma (12.3% and 39.6%) and the overall adenoma group (15.7% and 44.0%) (p=0.008 and p=0.006, respectively). Multivariate analysis revealed a positive CAVI and smoking status to be significantly associated with high-risk adenoma with an odds ratio of 1.595 (95% confidence interval 1.055–2.410, p=0.027) and 1.579 (1.072–2.324, p=0.021), respectively. Conclusions In this study, a significant correlation between positive CAVI and high-risk adenomas was observed. Therefore, CAVI may be a significant predictor for high-risk colorectal adenoma.

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/Aims: Chronic enteropathy associated with SLCO2A1 gene (CEAS), an inherited disease characterized by nonspecific intestinal ulcers, has emerged in the Japanese population via loss-of-function mutations in the SLCO2A1 gene. We aimed to investigate the clinical and genetic characteristics of Korean patients diagnosed with CEAS. Methods: From July 2018 to July 2021, we performed Sanger sequencing of the SLCO2A1 gene in 46 patients with chronic intestinal ulcers. CEAS was confirmed based on known SLCO2A1 mutations. We summarized the clinical characteristics of patients with confirmed CEAS. Results: Fourteen out of 46 patients (30.4%) had genetically confirmed CEAS, and two SLCO2A1variants were detected (splicing site variant c.940+1G>A and nonsense mutation [p.R603X] in SLCO2A1). Twelve patients (85.7%) were females and the median age at diagnosis of CEAS was 44.5 years. All patients presented with abdominal pain, and 13 patients (92.9%) presented with anemia (median hemoglobin, 9.6 g/dL). Ten patients (71.4%) had hypoalbuminemia (median, 2.7 g/dL). The most commonly involved site was the ileum (13/14, 92.9%). Manifestations of primary hypertrophic osteoarthropathy (PHO), such as digital clubbing, pachydermia, and periostosis were observed in five patients (28.6%) and two male patients and one female patient satisfied all major PHO diagnostic criteria. Conclusions The clinical and genetic characteristics of Korean patients with confirmed CEAS were similar to those reported in the literature. CEAS should be considered in the differential diagnosis for patients with unexplained chronic nonspecific ulcers of the small intestine.

Background/Aims: The prospective Crohn’s Disease Clinical Network and Cohort Study is a nationwide multicenter cohort study of patients with Crohn’s disease (CD) in Korea, aiming to prospectively investigate the clinical features and long-term prognosis associated with CD. Methods: Patients diagnosed with CD between January 2009 and September 2019 were prospectively enrolled. They were divided into two cohorts according to the year of diagnosis: cohort 1 (diagnosed between 2009 and 2011) versus cohort 2 (between 2012 and 2019). Results: A total of 1,175 patients were included, and the median follow-up duration was 68 months (interquartile range, 39.0 to 91.0 months). The treatment-free durations for thiopurines (p<0.001) and anti-tumor necrosis factor agents (p=0.018) of cohort 2 were shorter than those of cohort 1. Among 887 patients with B1 behavior at diagnosis, 149 patients (16.8%) progressed to either B2 or B3 behavior during follow-up. Early use of thiopurine was associated with a reduced risk of behavioral progression (adjusted hazard ratio [aHR], 0.69; 95% confidence interval [CI], 0.50 to 0.90), and family history of inflammatory bowel disease was associated with an increased risk of behavioral progression (aHR, 2.29; 95% CI, 1.16 to 4.50). One hundred forty-one patients (12.0%) underwent intestinal resection, and the intestinal resection-free survival time was significantly longer in cohort 2 than in cohort 1 (p=0.003). The early use of thiopurines (aHR, 0.35;95% CI, 0.23 to 0.51) was independently associated with a reduced risk of intestinal resection. Conclusions The prognosis of CD in Korea appears to have improved over time, as evidenced by the decreasing intestinal resection rate. Early use of thiopurines was associated with an improved prognosis represented by a reduced risk of intestinal resection.

Multiple endocrine neoplasia type 2A is autosomal dominantly inherited disease with RET oncogene mutation. Hyperparathyroidism occurs less frequently and severe hyperparathyroidism is rare in multiple endocrine neoplasia type 2A. We experienced a case of 38-year-old man with peptic ulcer perforation and hypercalcemia who was diagnosed as multiple neoplasia type 2A. Although peptic ulcer disease with hypercalcemia is very rare in MEN 2A, clinical suspicion of multiple endocrine neoplasia and germline mutational test would be important for accurate diagnosis and treatment.