Purpose: Determining the extent of radical lymphadenectomy at clinical early stage is challenging. We aimed to investigate the appropriate extent of lymphadenectomy in clinical early-stage right colon cancer. Methods: Patients with clinical stage 0 or I right colon cancer who underwent curative surgery from January 2007 to December 2021 were included in this retrospective study. The extent of lymph node (LN) metastases based on the distribution of LN metastases (LND: LND1 pericolic nodes, LND2 intermediate nodes, LND3 apical nodes), along with the depth of submucosal (SM) invasion (classed into SM1–3), were analyzed. Results: Of the 348 patients, distribution across pathologic stages was as follows: 30 patients (8.6%) at stage 0, 207 (59.5%) at stage I, 52 (14.9%) at stage II, and 59 (17.0%) at stage III. In pT1 tumor patients, LN metastases varied by SM invasion depth: 3.6% in SM1 (all LND1), 5.1% in SM2 (all LND1), and 17.5% in SM3 (LND1 10%, LND2 5%, LND3 2.5%). For pT2, pT3, and pT4 stages, LN metastasis rates were 16.2% (LND1 11.3%, LND2 3.8%, LND3 1.3%), 39.7% (LND1 28.9%, LND2 8.4%, LND3 2.4%), and 50% (LND1 25%, LND2 25%), respectively. Tumor invasion depth and lymphovascular invasion were identified as significant risk factors for LN metastasis extending to LND2–3. Conclusion Complete mesocolic excision should be considered for right-sided colon cancer because tumor infiltration deeper than SM2 could metastasize to LND2 or further. If preoperative endoscopy confirms SM1 or SM2 invasion, D2 lymphadenectomy could be a limited surgical option.

Purpose: Determining the extent of radical lymphadenectomy at clinical early stage is challenging. We aimed to investigate the appropriate extent of lymphadenectomy in clinical early-stage right colon cancer. Methods: Patients with clinical stage 0 or I right colon cancer who underwent curative surgery from January 2007 to December 2021 were included in this retrospective study. The extent of lymph node (LN) metastases based on the distribution of LN metastases (LND: LND1 pericolic nodes, LND2 intermediate nodes, LND3 apical nodes), along with the depth of submucosal (SM) invasion (classed into SM1–3), were analyzed. Results: Of the 348 patients, distribution across pathologic stages was as follows: 30 patients (8.6%) at stage 0, 207 (59.5%) at stage I, 52 (14.9%) at stage II, and 59 (17.0%) at stage III. In pT1 tumor patients, LN metastases varied by SM invasion depth: 3.6% in SM1 (all LND1), 5.1% in SM2 (all LND1), and 17.5% in SM3 (LND1 10%, LND2 5%, LND3 2.5%). For pT2, pT3, and pT4 stages, LN metastasis rates were 16.2% (LND1 11.3%, LND2 3.8%, LND3 1.3%), 39.7% (LND1 28.9%, LND2 8.4%, LND3 2.4%), and 50% (LND1 25%, LND2 25%), respectively. Tumor invasion depth and lymphovascular invasion were identified as significant risk factors for LN metastasis extending to LND2–3. Conclusion Complete mesocolic excision should be considered for right-sided colon cancer because tumor infiltration deeper than SM2 could metastasize to LND2 or further. If preoperative endoscopy confirms SM1 or SM2 invasion, D2 lymphadenectomy could be a limited surgical option.

Purpose: Determining the extent of radical lymphadenectomy at clinical early stage is challenging. We aimed to investigate the appropriate extent of lymphadenectomy in clinical early-stage right colon cancer. Methods: Patients with clinical stage 0 or I right colon cancer who underwent curative surgery from January 2007 to December 2021 were included in this retrospective study. The extent of lymph node (LN) metastases based on the distribution of LN metastases (LND: LND1 pericolic nodes, LND2 intermediate nodes, LND3 apical nodes), along with the depth of submucosal (SM) invasion (classed into SM1–3), were analyzed. Results: Of the 348 patients, distribution across pathologic stages was as follows: 30 patients (8.6%) at stage 0, 207 (59.5%) at stage I, 52 (14.9%) at stage II, and 59 (17.0%) at stage III. In pT1 tumor patients, LN metastases varied by SM invasion depth: 3.6% in SM1 (all LND1), 5.1% in SM2 (all LND1), and 17.5% in SM3 (LND1 10%, LND2 5%, LND3 2.5%). For pT2, pT3, and pT4 stages, LN metastasis rates were 16.2% (LND1 11.3%, LND2 3.8%, LND3 1.3%), 39.7% (LND1 28.9%, LND2 8.4%, LND3 2.4%), and 50% (LND1 25%, LND2 25%), respectively. Tumor invasion depth and lymphovascular invasion were identified as significant risk factors for LN metastasis extending to LND2–3. Conclusion Complete mesocolic excision should be considered for right-sided colon cancer because tumor infiltration deeper than SM2 could metastasize to LND2 or further. If preoperative endoscopy confirms SM1 or SM2 invasion, D2 lymphadenectomy could be a limited surgical option.

Objective: Double microcatheter technique (dMC) can be the alternative to Single microcatheter technique (sMC) for challenging cases, but there is lack of studies comparing dMC to sMC especifically for small ruptured aneurysms. Our objective was to compare the safety and efficacy of dMC to sMC in treating small (≤5 mm) and tiny (≤3 mm) ruptured aneurysms. Methods: This study focused on 91 out of 280 patients who had ruptured aneurysms and underwent either single or double microcatheter coil embolization. These patients were treated with either single or double microcatheter coil embolization. We divided the patients into two groups based on the procedural method and evaluated clinical features and outcomes. Subgroup analyses were conducted specifically for tiny aneurysms, comparing the two methods, and within the dMC group, we also examined whether the aneurysm was tiny or not. In addition, univariate logistic regression analysis was performed to assess the impact of coil packing density. Results: The mean values for most outcome measures in the dMC group were higher than those in the sMC group, but these differences did not reach statistical significance (coil packing density, 45.739% vs. 39.943%; procedural complication, 4.17% vs. 11.94%; recanalization, 8.3% vs. 10.45%; discharge discharge modified Rankin Scale (mRS), 1.83 vs. 1.97). The comparison between tiny aneurysms and other sizes within the dMC group did not reveal any significant differences in terms of worse outcomes or increased risk. The only factor that significantly influenced coil packing density in the univariate logistic regression analysis was the size of the aneurysm (OR 0.309, 95% CI 0.169–0.566, p=0.000). Conclusions The dMC proved to be a safe and viable alternative to the sMC for treating small ruptured aneurysms in challenging cases.

Colonic duplication constitutes a rare congenital anomaly, characterized by the presence of hollow cystic or tubular structures exhibiting an epithelial-lined intestinal wall. Diagnostic challenges persist due to its low incidence and manifestation of nonspecific symptoms such as abdominal pain or constipation, resulting in a reluctance to pursue surgical resection. As associated malignancies in colonic duplication are rare, the inherent malignant potential of these anomalies remains undetermined. Additionally, despite reported instances of associated malignancies in colonic duplication, there is an absence of reports in the literature detailing tubular adenoma within these cases. The histologic features of the presented case are particularly noteworthy, situated at the precancerous stage, intimating potential progression towards adenocarcinoma within colonic duplication.

BACKGROUND/OBJECTIVES: This study aimed to evaluate the effect of preoperative immunonutrition on the composition of fecal microbiota following a colon cancer surgery.MATERIALS/METHODS: This study was a secondary analysis of a randomized controlled trial assessing the impact of preoperative immunonutrition on the postoperative outcomes of colon cancer surgery. Patients with primary colon cancer were enrolled and randomly assigned to receive additional preoperative immunonutrition or a normal diet alone.Oral nutritional supplementation (400 mL/day) with arginine and ω-3 fatty acids were administered to patients in the immunonutrition group for 7 days prior to surgery. Thirtytwo fecal samples were collected from 16 patients in each group, and the composition of fecal microbiota was compared between the 2 groups. RESULTS: At the phylum level, no significant difference was observed in the composition of microbiota between the 2 groups (Firmicutes, 69.1% vs. 67.5%, P = 0.624; Bacteroidetes, 19.3% vs. 18.1%, P = 0.663; Actinobacteria, 6.7% vs. 10.6%, P = 0.080). The Firmicutes/Bacteroidetes ratio (4.43 ± 2.32 vs. 4.55 ± 2.51, P = 0.897) was also similar between the 2 groups. At the genus level, the proportions of beneficial bacteria such as Faecalibacterium spp. (8.1% vs. 6.4%, P = 0.328) and Prevotella spp. (6.9% vs. 4.8%, P = 0.331) were higher, while that of Clostridium spp. was lower (0.5% vs. 1.2%, P = 0.121) in the immunonutrition group, but the difference was not significant. CONCLUSIONS Immunonutrition showed no significant association with the composition of fecal microbiota. The relationship between immunonutrition and the fecal microbiota should be investigated further in large-scale studies.

Purpose: The relationship between microsatellite instability (MSI) and tumor response after neoadjuvant chemoradiotherapy (nCRT) in rectal cancer remains unclear. The present study aimed to evaluate the association between MSI and tumor response to nCRT in rectal cancer treatment. Methods: Patients with rectal cancer from 2 tertiary hospitals who underwent nCRT, followed by radical surgery, were included. The microsatellite status was determined using a PCR-based Bethesda panel. Tumors with a Dworak’s tumor regression grade of 3 or 4 were considered to have a good response. Predictive factors for a good response to nCRT were analyzed. Results: Of the 1,401 patients included, 910 (65.0%) had MSI results and 1.5% (14 of 910) showed MSI-H. Among all the patients, 519 (37.0%) showed a good response to nCRT. A univariate analysis showed that MSI-H tended to be negatively associated with a good response to nCRT, but no statistical significance was observed (7.1% vs. 24.1%, P = 0.208).Multivariate analysis showed that well-differentiated tumors were the only predictive factor for good response to nCRT (odds ratio [OR], 2.241; 95% confidence interval [CI], 1.492–3.364; P < 0.001). MSI status tended to be associated with the response to nCRT (OR, 0.215; 95% CI, 0.027–1.681; P = 0.143). Conclusion MSI-H was not associated with response to nCRT in patients with rectal cancer.

Purpose: Some studies have suggested that circumferential tumor location (CTL) of rectal cancer may affect oncological outcomes. However, studies after preoperative chemoradiotherapy (CRT) are rare. This study aimed to evaluate the impact of CTL on oncologic outcomes of patients with mid to low rectal cancer who received preoperative CRT. Methods: Patients with mid to low rectal cancer who underwent total mesorectal excision after CRT from January 2013 to December 2018 were included in this retrospective study. The impact of CTL on the pathological circumferential resection margin (CRM) status, local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS) was analyzed. Results: Of the 381 patients, 98, 70, 127, and 86 patients were categorized into the anterior, posterior, lateral, and circumferential tumor groups, respectively. Tumor location was not significantly associated with the pathological CRM involvement (anterior, 12.2% vs. posterior, 14.3% vs. lateral, 11.0% vs. circumferential, 17.4%; P = 0.232). Univariate analyses revealed no correlation between CTL and 3-year LRFS (93.0% vs. 89.1% vs. 91.5% vs. 88%, P = 0.513), 3-year DFS (70.3% vs. 70.2% vs. 75.3% vs. 75.7%, P = 0.832), and 5-year OS (74.7% vs. 78.0% vs. 83.9% vs. 78.2%, P = 0.204). Multivariate analysis identified low rectal cancer and pathological CRM involvement as independent risk factors for all survival outcomes (all P < 0.05). Conclusion CTL of rectal cancer after preoperative CRT was not significantly associated with the pathological CRM status, recurrence, and survival.

Purpose: This study aimed to evaluate the relationship between high-output stomas (HOSs), postoperative ileus (POI), and readmission after rectal cancer surgery with diverting ileostomy. Methods: We included 302 patients with rectal cancer who underwent restorative resection with diverting ileostomy between January 2011 and December 2015. HOSs were defined as stomas with ≥ 2,000 mL/day output. We analyzed predictive factors for readmission of these patients. Results: Forty-eight patients (15.9%) had HOSs during the hospital stay, and 41 patients (13.6%) experienced POI. HOSs were strongly associated with POI (45.8% vs. 7.5%, P < 0.001). The all-cause readmission rate was 16.9%, with 19 (6.3%) and 20 (6.6%) experiencing ileus and acute kidney injury, respectively. HOSs (27.1% vs. 15.0%, P = 0.040) and POI (34.1% vs. 14.2%, P = 0.002) were associated with all-cause readmission, and POI was associated with readmission with ileus (17.1% vs. 4.6%, P = 0.007). POI was an independent risk factor for all-cause readmission (adjusted odds ratio [OR], 2.640; 95% confidence interval [CI], 1.162 to 6.001; P = 0.020) and readmission with ileus (adjusted OR = 3.869; 95% CI 1.387 to 10.792; P = 0.010). Conclusion POI was associated with readmission, particularly for subsequent ileus, in patients with diverting ileostomy. We should make efforts to reduce POI, such as strong control of HOSs, to prevent readmission.

Background/Aims: Pheochromocytoma and paraganglioma (PPGL) are catecholamine-producing tumors that can cause blood pressure (BP) elevation and cardiovascular complications. Clinical presentation of these tumors may be changed through widespread use of imaging studies, which enables detection of PPGLs before onset of symptoms. We investigated clinical profiles of patients with surgically resected PPGLs. Methods: From 2005 to 2017, 111 consecutive patients with surgically resected PPGLs in two tertiary hospitals in Korea were studied. Results: Mean age was 52 ± 16 years, 57 patients (51.4%) were male and 54 (48.6%) were hypertensive. Twenty-nine PPGLs (26.1%) were extra-adrenal paragangliomas. Sixteen (14.4%) and seven patients (6.3%) (Group 1, n = 23) were diagnosed during work-up of hypertension and transient cardiomyopathy respectively, and the remainder (Group 2, n = 88) were incidentalomas detected during routine abdominal imaging. Patients in the Group 1 were younger and more frequently symptomatic, and had higher BPs, heart rates and levels of urinary catecholamines than those in the Group 2. Paragangliomas were less frequent and secretion of epinephrine and metanephrine was more predominant in the Group 1 than in Group 2. After the surgical resections, 18.2% of patients still needed antihypertensive medications. Conclusions Out of 111 patients with surgically resected PPGLs, 88 (79.3%) were diagnosed as incidentalomas. Seven patients presented with transient cardiomyopathy and 16 with hypertension. Tumor location and secretion of catecholamine may vary depending on the presence of symptoms.