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.

Purpose: Bladder preservation chemoradiotherapy (CRT) in patients with a clinical complete response (cCR) following cisplatin-based neoadjuvant chemotherapy (NAC) is a promising treatment strategy for muscle-invasive bladder urothelial carcinoma (MIBC). A combined analysis of raw data from two prospective phase II studies was performed to better evaluate the feasibility of selective bladder preservation CRT. Materials and Methods: The analysis was based on primary efficacy data from two independent studies, including 76 MIBC patients receiving NAC followed by bladder preservation CRT. The efficacy data included metastasis-free survival (MFS) and disease-free survival (DFS). For the present analysis, starting point of survival was defined as the date of commencing CRT. Results: Among 76 patients, 66 had a cCR following NAC. Sixty-four patients received gemcitabine and cisplatin (GC) combination chemotherapy in neoadjuvant setting, and 12 received nivolumab plus GC. Bladder preservation CRT following NAC was generally well-tolerated, with low urinary tract symptoms being the most common late complication. With a median follow-up of 64 months, recurrence was recorded in 43 patients (57%): intravesical only (n=20), metastatic only (n=16), and both (n=7). In 27 patients with intravesical recurrence, transurethral resection, and Bacillus Calmette-Guerin treatment was given to 17 patients. Salvage cystectomy was performed in 10 patients. Median DFS was 46.3 (95% confidence interval [CI], 25.1 to 67.5) months, and the median MFS was not reached. Neither DFS nor MFS appeared to be affected by any of the baseline characteristics. However, DFS was significantly longer in patients with a cCR than in those without (hazard ratio, 0.465; 95% CI, 0.222 to 0.976). Conclusion The strategy of NAC followed by selective bladder preservation CRT based on the cCR is feasible in the treatment of MIBC. A standardized definition of cCR is needed to better assess disease status post-NAC.

Background: We aimed to analyze the impact of concomitant Maze procedure on the clinical and rhythm outcomes, and echocardiographic parameters in tricuspid repair for patients with severe tricuspid regurgitation (TR) and persistent atrial fibrillation (AF). Methods: Patients who had severe TR and persistent AF and underwent tricuspid valve (TV) repair were included in the study. Both primary TR and secondary TR were included in the current study. The study population was stratified according to Maze procedure. The primary outcome was major adverse cardiovascular and cerebrovascular event (MACCE) at 15 years postsurgery. Propensity-score matching analyses was performed to adjust baseline differences. Results: Three hundred seventy-one patients who underwent tricuspid repair for severe TR and persistent AF from 1994 to 2021 were included, and 198 patients (53.4%) underwent concomitant Maze procedure. The maze group showed 10-year sinus rhythm (SR) restoration rate of 55%. In the matched cohort, the maze group showed a lower cumulative incidence of cardiac death (4.6% vs. 14.4%, P = 0.131), readmission for heart failure (8.1% vs. 22.2%, P = 0.073), and MACCE (21.1% vs. 42.1%, P = 0.029) at 15 years compared to the non-maze group. Left atrial (LA) diameter significantly decreased in the maze group at 5 years (53.3 vs. 59.6 mm, P < 0.001) after surgery compared to preoperative level, and there was a significant difference in the change of LA diameter over time between the two groups (P = 0.013). Conclusion The Maze procedure during TV repair in patients with severe TR and persistent AF showed acceptable SR rates and lower MACCE rates compared to those without the procedure, while also promoting LA reverse remodeling.

Background and Objectives: Early diastolic mitral annular tissue (e’) velocity is a commonly used marker of left ventricular (LV) diastolic function. This study aimed to investigate the prognostic implications of e’ velocity in patients with mitral regurgitation (MR). Methods: This retrospective cohort study included 1,536 consecutive patients aged <65 years with moderate or severe chronic primary MR diagnosed between 2009 and 2018. The primary and secondary outcomes were all-cause and cardiovascular mortality, respectively.According to the current guidelines, the cut-off value of e’ velocity was defined as 7 cm/s. Results: A total of 404 individuals were enrolled (median age, 51.0 years; 64.1% male; 47.8% severe MR). During a median 6.0-year follow-up, there were 40 all-cause mortality and 16 cardiovascular deaths. Multivariate analysis revealed a significant association between e’ velocity and all-cause death (adjusted hazard ratio [aHR], 0.770; 95% confidence interval [CI], 0.634–0.935; p=0.008) and cardiovascular death (aHR, 0.690; 95% CI, 0.477–0.998;p=0.049). Abnormal e’ velocity (≤7 cm/s) independently predicted all-cause death (aHR, 2.467; 95% CI, 1.170–5.200; p=0.018) and cardiovascular death (aHR, 5.021; 95% CI, 1.189–21.211; p=0.028), regardless of symptoms, LV dimension and ejection fraction. Subgroup analysis according to sex, MR severity, mitral valve replacement/repair, and symptoms, showed no significant interactions. Including e’ velocity in the 10-year risk score improved reclassification for mortality (net reclassification improvement [NRI], 0.154; 95% CI, 0.308– 0.910; p<0.001) and cardiovascular death (NRI, 1.018; 95% CI, 0.680–1.356; p<0.001). Conclusions In patients aged <65 years with primary MR, e’ velocity served as an independent predictor of all-cause and cardiovascular deaths.

Purpose: This study aimed to analyze the treatment outcomes of combined definitive radiation therapy (RT) and androgen deprivation therapy (ADT) for clinically node-positive prostate cancer. Materials and Methods: Medical records of 60 patients with clinically suspected metastatic lymph nodes on radiological examination were retrospectively analyzed. Eight patients (13.3%) were suspected to have metastatic common iliac or para-aortic lymph nodes. All patients underwent definitive RT with a dose fractionation of 70 Gy in 28 fractions. ADT was initiated 2–3 months before RT and continued for at least 2 years. Biochemical failure rate (BFR), clinical failure rate (CFR), overall survival (OS), and prostate cancer-specific survival (PCSS) were calculated, and genitourinary and gastrointestinal adverse events were recorded. Results: The median follow-up period was 5.47 years. The 5-year BFR, CFR, OS, and PCSS rates were 19.1%, 11.3%, 89.0%, and 98.2%, respectively. The median duration of ADT was 2.30 years. BFR and CFR increased after 3 years, and 11 out of 14 biochemical failures occurred after the cessation of ADT. Grade 2 and beyond late genitourinary and gastrointestinal toxicity rates were 5.0% and 13.3%, respectively. However, only two grade 3 adverse events were reported, and no grade 4–5 adverse events were reported. Patients with non-regional lymph node metastases did not have worse BFR, CFR, or adverse event rates. Conclusion This study reported the efficacy and tolerable toxicity of hypofractionated definitive RT combined with ADT for clinically node-positive prostate cancer. Additionally, selected patients with adjacent non-regional lymph node metastases might be able to undergo definitive RT combined with ADT.

Objective: To identify factors that affect the participation of female immigrants in their 20s in the national cervical cancer screening programs. Methods: Data were obtained from the National Health Insurance Services from 2016 to 2017. A total of 17,730 women who agreed to undergo cervical cancer screening during 2016-2017 were included in the study. Results: Of the 17,730 women, 8,149 (46%) participated in cervical cancer screening, whereas, 9,581 (54%) did not. Logistic regression analysis of factors related to cervical cancer screening showed that the odds ratio (OR) of screening was higher in short duration of stay (OR, 1.18; 95% confidence interval [CI], 1.03-1.35), Chinese nationality (OR, 1.43; 95% CI, 1.28-1.59), unemployment (OR, 1; 95% CI, reference), participation in general health screening (OR, 4.16; 95% CI, 3.24-5.33), and comorbidities (OR, 1.16; 95% CI, 1.09-1.24) when compared to the other populations. The highest OR was associated with participation in general health screening. Conclusion Appropriate programs should be developed to increase participation of socially vulnerable groups in cervical cancer screening. Such programs will improve awareness regarding cervical cancer screening and reduce disparities in healthcare.

Purpose: The activity and safety of neoadjuvant nivolumab plus gemcitabine/cisplatin (N+GC) were tested in patients with muscle-invasive bladder urothelial carcinoma (MIBC). Materials and Methods: In a prospective phase II trial, patients with cT2-T4a N0 MIBC who were eligible for cisplatin and medically appropriate to undergo radical cystectomy (RC) were enrolled. Treatment with nivolumab 3 mg/kg on days 1 and 15 plus GC (cisplatin 70 mg/m2 on day 1, and gemcitabine 1,000 mg/m2 on days 1, 8, and 15) was repeated every 28 days up to 3 or 4 cycles, depending on the surgery schedules. The primary endpoint was pathologic complete response (pCR, ypT0). Secondary endpoints included pathologic downstaging (≤ ypT1), disease-free survival (DFS), and safety. Results: Between September 2019 and October 2020, 51 patients were enrolled. Neoadjuvant N+GC was well tolerated. Among 49 patients who completed neoadjuvant N+GC, clinical complete response (cCR) was achieved in 59% of intent-to-treat (ITT) population. RC was performed in 34 (69%) patients. pCR was achieved in 24% (12/49) of ITT population and 35% (12/34) of RC patients. Median DFS was not reached. Over a median follow-up of 24 months, 12 patients experienced disease recurrence and were treated with palliative therapy or surgery. Although 12 patients declined surgery and were treated with concurrent chemoradiotherapy, DFS was longer in patients with cCR after neoadjuvant therapy than those without. Preoperative programmed death-ligand 1 (PD-L1) did not correlate with pCR or pathologic downstaging rates. Conclusion Neoadjuvant N+GC was feasible and provided meaningful pathologic responses in patients with MIBC, regardless of baseline PD-L1 expression (ONO-4538-X41; CRIS.nih.go.kr, KCT0003804).

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.

There are various approaches to treatment for patients with fully edentulous jaw. In maxilla, it is easy to obtain sufficient stability, support, and retention with the traditional full denture method. In mandible, however, there are difficulties caused by anatomical limitations. In this case, treatment with implants can be considered. If it is difficult to place implants in posterior area, a fixed complete denture can be considered, using 4 - 5 implants anterior to mental foramen. This approach has changed in many ways, such as surgical methods and materials used, over the years. This case report compares two approaches and their changes over time, especially in the cases of mandibular fixed prostheses using implants, paired with maxillary complete denture.

Purpose: There are no effective treatment methods with which to control complications of radiation proctitis with fistula or recurrent bleeding following radiation treatment for prostate, cervical, or rectal cancer. Mesenchymal stem cells (MSCs) can induce immune modification, resulting in tissue repair and regeneration. Therefore, we used a rat model of radiation-induced proctitis and observed the effects of using human placenta-derived (PD) and adipose tissue-derived (AD) MSCs. Materials and Methods: Female Sprague Dawley rats were irradiated at the pelvic area with 25 Gy. We injected 1×10 6 cells of human PD-MSCs, human AD-MSCs, human foreskin fibroblasts, and control media into the rectal submucosa following irradiation. We sacrificed rats for pathologic evaluation. Results: Fibrosis on the rectum was reduced in both MSC groups, compared to the control group. Mucosal Ki-67 indices of both MSC injected groups were higher than those in the control group. Although caspase-3 positive cells in the mucosa gradually increased and decreased in the control group, those in both MSC injected groups increased rapidly and decreased thereafter. Conclusion We demonstrated the effects of regional MSC injection treatment for radiation-induced proctitis in rats. MSC injection reduced fibrosis and increased proliferation in rat mucosa. Human AD-MSCs and PD-MSCs had similar effectiveness.