Efficacy and safety of a submucosal injection solution of sodium alginate for endoscopic resection in a porcine model.

Endoscopic resection techniques require the use of submucosal injection. Normal saline and sodium hyaluronate solutions are mainly used for this purpose, but an ideal solution has not yet been developed. The aim of this study was to assess a new solution, MC-003-a novel submucosal injection solution developed with sodium alginate as the main ingredient. Normal saline, a commercial sodium hyaluronate solution (Endo-Ease), and MC-003 were examined. A total of 18 gastric submucosal cushions were created in the stomachs of six pigs. The height of mucosal elevation was measured sequentially using endoscopic sonography. After euthanizing the animals either 2 h or 5 days after the procedure, pathologic examination was performed for each injection site. Although not statistically significant over the entire study period, MC-003 showed a superior result to normal saline and an equivalent result to Endo-Ease in the submucosal cushion height and its rate of decrease. There were no adverse outcomes after injection of the three solutions and there was no pathologically identified detrimental change in the resected specimens. MC-003 creates a sufficient submucosal fluid cushion without apparent tissue damage. It can be considered as an effective submucosal injection material.

Unveiling the profound advantages of total neoadjuvant therapy in rectal cancer: a trailblazing exploration.

The standard treatments for locally advanced rectal cancer typically involved neoadjuvant therapy with either short-course radiation or long-course chemoradiation, followed by radical surgery and adjuvant chemotherapy. While the advancement of surgical techniques and the adoption of multimodal therapy have greatly contributed to reducing local failure, there has been limited improvement in overall survival, primarily due to the stagnation in systemic failure. In response to this challenge, a new strategy known as total neoadjuvant therapy (TNT) has emerged, involving the administration of both full-dose chemotherapy and radiation before surgery. It has shown promise in reducing systemic failure, enhancing tumor regression, and improving treatment adherence, ushering in a new era in the standard treatment of locally advanced rectal cancer. This review aims to summarize the evolution of multimodal treatments for locally advanced rectal cancer, ultimately converging into the current TNT strategy, and provides an assessment of the benefits and limitations of TNT based on available evidence, serving as a foundation for selecting the best treatment option.

RNA-Seq-Based Molecular Classification Analyses in Colorectal Cancer and Synchronous Adenoma.

Colorectal cancers (CRC) are classified into consensus molecular subtypes (CMS) based on gene expression profiles. The revised classification system iCMS was proposed by considering intrinsic epithelial status, microsatellite instability (MSI), and fibrosis. This study aimed to provide molecular evidence for the adenoma-carcinoma sequence concept by examining CRC and synchronous adenomas using iCMS. Epithelial CMS cell proportion was estimated using CiberSortx, an in silico cell fractionation method that included CMS cell types among the reference cell types. A random forest (RF) model estimated the posterior probabilities of CMS classes, which were compared with the CiberSortx results. Gene expression profiles of the published iCMS signature panel were retrieved from our dataset and subjected to heatmap clustering for classification. Bulk RNA sequencing data were collected from 29 adenocarcinomas and 11 adenoma samples. CiberSortx showed all CRC contained either CMS2 or CMS3 as the major epithelial cancer cell type. The RF model classified approximately half of the CRC as CMS4, whereas CMS4 was hardly detected by CiberSortx. Because they were enriched with myofibroblasts as per the CiberSortx classification, we tentatively designated them as iCMS2-F/iCMS3-F. iCMS coupled with the application of an in silico cell fractionation method can provide the molecular dissection of CRC and adenoma.

Short- and long-term outcomes of subtotal/total colectomy in the management of obstructive left colon cancer.

PURPOSE: Surgical management of obstructive left colon cancer (OLCC) is still a matter of debate. The classic Hartmann procedure (HP) has a disadvantage that requires a second major operation. Subtotal colectomy/total abdominal colectomy (STC/TC) with ileosigmoid or ileorectal anastomosis is proposed as an alternative procedure to avoid stoma and anastomotic leakage. However, doubts about morbidity and functional outcome and lack of long-term outcomes have made surgeons hesitate to perform this procedure. Therefore, this trial was designed to provide data for morbidity, functional outcomes, and long-term outcomes of STC/TC. METHODS: This study retrospectively analyzed consecutive cases of OLCC that were treated by STC/TC between January 2000 and November 2020 at a single tertiary referral center. Perioperative outcomes and long-term outcomes of STC/TC were analyzed. RESULTS: Twenty-five descending colon cancer (45.5%) and 30 sigmoid colon cancer cases (54.5%) were enrolled in this study. Postoperative complications occurred in 12 patients. The majority complication was postoperative ileus (10 of 12). Anastomotic leakage and perioperative mortality were not observed. At 6 to 12 weeks after the surgery, the median frequency of defecation was twice per day (interquartile range, 1-3 times per day). Eight patients (14.5%) required medication during this period, but only 3 of 8 patients required medication after 1 year. The 3-year disease-free survival was 72.7% and 3-year overall survival was 86.7%. CONCLUSION: The risk of anastomotic leakage is low after STC/TC. Functional and long-term outcomes are also acceptable. Therefore, STC/TC for OLCC is a safe, 1-stage procedure that does not require diverting stoma.

Clinical outcomes and prognostic factors of cone-beam CT-guided radiofrequency ablation for pulmonary metastases in colorectal cancer patients.

AIM: Radiofrequency ablation (RFA) has been increasingly used for the treatment of pulmonary metastases in various malignancies. METHODS: A retrospective analysis was performed to establish the safety and efficacy of cone-beam computed tomography (CBCT)-guided RFA in patients with metastatic colorectal cancer between 2016 and 2019, and the prognostic factors of local tumor control were assessed. RESULTS: A total of 31 patients with colorectal cancer underwent 48 sessions of lung RFA. The mean diameter of metastases targeted for RFA was 11 mm (range: 4-32), and the RFA was technically successful in 43 sessions (90%). There were 14 complications (29%), the majority of which required no intervention, with no cases of mortality. The median follow-up duration from RFA in the surviving 29 patients was 18.0 months. Only two patients (6%) died of disease progression, and the 3-year overall survival rate was 91% (95% CI: 83-99). Local tumor progression (LTP) of the RFA site was observed in 27%, and the LTP-free survival rates at 1 and 2 years were 81% (95% CI: 70-82) and 64% (95% CI: 50-77), respectively. Multivariate analysis showed that the progression of extra-RFA sites and the presence of extrapulmonary metastasis were independent prognostic factors significantly associated with LTP at RFA site. CONCLUSION: Lung RFA using CBCT guidance is a comparatively safe and effective option for the treatment of lung metastases from colorectal cancer. However, the control of extrapulmonary metastases should be accompanied by combined or sequential systemic treatment and local treatment.

Epidemiology, Risk Factors, and Prevention of Colorectal Cancer-An English Version.

Colorectal cancer (CRC) is the fourth most common malignancy in Korea and has been ranked as the third leading cause of cancer deaths in 2020. Although the incidence and mortality rates of CRC have decreased in recent years in Korea, it is still a significant public health burden. From the early 1990s until the mid-2000s, the 5-year relative survival of patients with CRC in Korea continuously increased. This finding appears to be a consequence of the successful introduction of a government-led screening program; the development of improved surgical techniques, anticancer drugs, and adjuvant treatment; and the advancement of medical resources and infrastructure along with economic growth. However, the improvement in survival has stagnated since the late 2000s. The recent coronavirus disease 2019 outbreak led to a reduction in hospital visits and screenings, which is expected to cause a stage shift to advanced disease stages and a worse prognosis for patients with CRC. Exploring modifiable environmental risk factors and appropriate screening test methods in Korea is necessary to overcome these challenges. Primary prevention through risk factor mediation and secondary prevention using suitable screening programs can help reduce the incidence and mortality rates of CRC.

Aspergillus appendicitis complicating chemotherapy of leukemia: A case report and review of the literature.

INTRODUCTION: The diagnosis of primary Aspergillus appendicitis can be missed or delayed because of its rarity. We report our experience of a case of Aspergillus appendicitis complicating chemotherapy of leukemia. PRESENTATION OF CASE: A 48-year-old man who was diagnosed with acute myeloid leukemia developed high fever and epigastric pain two weeks after administration of his fourth consolidation chemotherapy. Right lower quadrant tenderness and rebound tenderness were noticed on physical examination, and the abdomen and pelvis computed tomography suggested acute perforated appendicitis with localized peritonitis. Emergency laparoscopy showed an inflamed appendix, which was resected. Pathology reports revealed invasive aspergillosis in the appendix. The patient recovered after high-dose antifungal therapy, although he required prolonged hospitalization. DISCUSSION: Acute appendicitis is very rarely caused by fungi infection with an overall incidence of up to 1.15 %. Differential diagnosis of fungal appendicitis without pathology report is challenging due to low incidence. CONCLUSION: Isolated Aspergillus appendicitis is a rare disease that can progress without appropriate antifungal therapy even after surgical resection of the appendix. Surgeons should pay attention to pathology reports after appendectomy to avoid missing unusual cases, especially in immunocompromised patients.

Validation of a scoring system to predict bladder dysfunction after laparoscopic rectal cancer surgery.

PURPOSE: A recent trend in  urinary catheter management in patients who underwent laparoscopic rectal cancer surgery is early removal. However, some patients develop bladder dysfunction and require urinary re-catheterization. In 2016, a scoring system to predict bladder dysfunction after laparoscopic rectal cancer surgery was developed in our institution. The aim of this study was to demonstrate the validity of this scoring system and to determine the suitability of patients for early removal of urinary catheter. METHODS: A single-center, retrospective study from a prospective database was conducted on 234 patients who underwent elective laparoscopic rectal cancer surgery between January 2016 and December 2019. According to bladder dysfunction predictive score, the urinary catheter was removed on the first postoperative day (low-risk group) and fifth postoperative day (high-risk group). After catheter removal, all patients were managed using in-house protocols. RESULTS: Of 234 patients, 130 (55.6%) were classified as a low-risk group. The overall incidence of bladder dysfunction was 8.5% (11/130) in the low-risk group and 13.5% (14/104) in the high-risk group. CONCLUSION: The scoring system developed to predict bladder dysfunction showed good overall performance for discriminating between patients suitable or not for early removal of urinary catheter after laparoscopic rectal cancer surgery.

Comparison of blowhole colostomy and loop ostomy for palliation of acute malignant colonic obstruction.

PURPOSE: Surgery to create a stoma for decompression might be required for unresectable stage IV cancer patients with complete colonic obstruction. The aim of this study was to compare the results of blowhole colostomy with those of loop ostomy. METHODS: Palliative ileostomy or colostomy procedures performed at a single center between January 2011 and October 2020, were analyzed retrospectively. Fifty-nine patients were identified during this period. The demographic characteristics and outcomes between the blowhole colostomy group (n=24) and the loop ostomy group (n=35) were compared. RESULTS: The median operative time tended to be shorter in the blowhole colostomy group (52.5 minutes; interquartile range [IQR], 43-65) than in the loop ostomy group (60 minutes; IQR, 40-107), but the difference did not reach statistical significance (P=0.162). The median length of hospital stay was significantly shorter with blowhole colostomy (blowhole, 13 days [IQR, 9-23]; loop, 21 days [IQR, 14-37]; P=0.013). Mean cecum diameter was significantly larger in the blowhole group than in the loop group (8.83±1.91 cm vs. 6.78±2.36 cm, P=0.001), and the emergency operation rate was higher in the blowhole group than in the loop group (22 of 24 [91.7%] vs. 23 of 35 [65.7%], P=0.021). CONCLUSION: In surgical emergencies, diverting a blowhole colostomy can be safe and effective for palliative management of colonic obstruction in patients with end-stage cancer and might reduce the operative time in emergent situations.

Risk factors for hemorrhoidal disease among healthy young and middle-aged Korean adults.

Hemorrhoidal disease is a highly prevalent anorectal condition causing substantial discomfort, disability, and decreased quality of life. Evidence on preventable risk factors for hemorrhoidal disease is limited. We conducted a cross-sectional study of 194,620 healthy men and women who completed a health screening exam including colonoscopy in 2011-2017. We evaluated potential risk factors of hemorrhoidal disease, including lifestyle factors, medical history, birth history, gastrointestinal symptoms, and anthropometric measurements. The prevalence of hemorrhoidal disease was 16.6%, and it was higher in females than in males (17.2 vs. 16.3%; P < 0.001). Compared to men, the prevalence of hemorrhoidal disease was higher in parous women (adjusted odds ratio [OR] 1.06; 95% confidence interval [CI] 1.02-1.10), and lower in nulliparous women (adjusted OR 0.92; 95% CI 0.86-0.98). In the adjusted analyses, older age, female sex, smoking, overweight, and being hypertensive were independently associated with the presence of hemorrhoidal disease. The prevalence of hemorrhoidal disease was positively associated with body mass index and waist circumference in parous women. The prevalence of hemorrhoidal disease was higher in older age, females, ever-smokers, and hypertensive participants. The association of excess adiposity with the prevalence of hemorrhoidal disease differed by sex and parity.

Early experience with laparoscopic treatment of liver tumors using a separable cluster electrode with a no-touch technique.

INTRODUCTION: Radiofrequency ablation (RFA) is one of the best curative treatments for hepatocellular carcinoma in selected patients, and this procedure can be applied either percutaneously or laparoscopically. Laparoscopic RFA has the benefit of direct visual control of the RFA procedure. Cluster electrodes (Octopus RF electrodes) can create a common ablation zone. AIM: Using these two methods (laparoscopic approach and no touch technique), this present study evaluated the technical and clinical outcomes of early experience with laparoscopic RFA and a no-touch technique. MATERIAL AND METHODS: Between November 2015 and November 2018, 21 patients underwent laparoscopic RFA for hepatocellular carcinoma with a no-touch technique using cluster electrodes. Laparoscopic RFA is recommended for patients with a contraindication for surgical resection, patients wants and a relative contraindication for conventional percutaneous RFA, such as lesions adjacent to the gastrointestinal tract, gallbladder, bile duct, or heart. RESULTS: In the 21 tumors, 2 were treated with a single electrode, 12 with 2 electrodes, and 7 tumors with 3 electrodes. The mean time of ablation per lesion was 20.43 ±8.77 min. There was no mortality, local tumor progression, delayed destructive biliary damage, or liver abscess at the follow-up computed tomography. No technical failures occurred. CONCLUSIONS: Laparoscopic RFA can access lesions for which percutaneous RFA is contraindicated or risky. Cluster electrodes can create sufficient ablation zones without contact and can achieve a sufficient margin with a low complication rate and no tumor dissemination. Therefore, laparoscopic RFA with a no-touch technique might be a safe and feasible treatment for HCC tumor in selected patients.

Clinicopathological characteristics and outcomes of gastrointestinal stromal tumors with high progranulin expression.

BACKGROUND & AIMS: Progranulin (PGRN) is known to promote tumorigenesis and proliferation of several types of cancer cells. However, little is known about the clinicopathological features of patients with gastrointestinal stromal tumors (GISTs) with regard to PGRN expression. METHODS: A retrospective analysis was performed on patients with GISTs who underwent curative surgical resection between 2007 and 2017. PGRN expression was evaluated by immunohistochemical (IHC) analysis and semi-quantitatively categorized (no expression, 0; weak, 1+; moderate, 2+; strong, 3+). Tumors with a staining intensity of 2+ or 3+ were considered high PGRN expression. RESULTS: Fifty-four patients were analyzed; 31 patients (57%) were male. The median age at surgery was 60 years (range, 33-79), and the most common primary site was the stomach (67%). Thirty-five patients (65%) had spindle histology; 42 patients (78%) were separated as a high-risk group according to the modified National Institutes of Health (NIH) classification. High PGRN-expressing tumors were observed in 27 patients (50%), had more epithelioid/mixed histology (68% vs. 32%; p = 0.046), and KIT exon 11 mutations (76% vs. 24%; p = 0.037). Patients with high PGRN-expressing tumors had a worse recurrence-free survival (RFS) (36% of 5-year RFS) compared to those with low PGRN-expressing tumors (96%; p<0.001). Multivariate analysis showed that high PGRN expression and old age (>60 years) were independent prognostic factors for poor RFS. CONCLUSIONS: High PGRN-expressing GISTs showed more epithelioid/mixed histology and KIT exon 11 mutations. PGRN overexpression was significantly associated with poor RFS in patients with GISTs who underwent curative resection.

Prognostic value of carcinoembryonic antigen and carbohydrate antigen 19-9 in periampullary cancer patients receiving pancreaticoduodenectomy.

BACKGROUND: We assessed the use of serum concentrations of carbohydrate antigen (CA) 19-9 and carcinoembryonic antigen (CEA) measured during the preoperative diagnostic workup as prognostic factors for survival in patients with periampullary carcinoma. METHODS: A retrospective review of patients diagnosed with periampullary carcinoma who underwent radical surgery was conducted. Factors related to the survival of periampullary carcinoma patients, including CA 19-9 and CEA, were analyzed. RESULTS: The mean age of the 112 patients included in the results was 66.41 ± 10.513 years. In the study, the percentage of patients with elevated serum CA 19-9 and CEA concentrations was 65.2% and 24.1%, respectively. CA 19-9 concentrations were correlated with the tumor stage, pre-operative jaundice, and lymphovascular invasion, but CEA concentrations were not. The median overall survival was longer for the normal serum CA 19-9 group than the group with increased CA 19-9 (56 months vs. 25 months, p = 0.003); however, there was no statistically significant difference between the normal serum CEA group and the group with increased CEA (43 months vs. 25 months, p = 0.077). Independent factors related to overall survival were sex, age, stage, presence of jaundice, lymphovascular invasion, perineural invasion, margin status, and elevated serum CA 19-9 concentrations. CONCLUSIONS: Periampullary carcinoma patients with elevated serum CA 19-9 concentrations at diagnosis are expected to have poor overall survival. CA 19-9 may be a useful marker for predicting prognosis in patients with periampullary carcinoma at the time of diagnosis.

Surgical outcomes of percutaneous transhepatic gallbladder drainage in acute cholecystitis grade II patients according to time of surgery.

BACKGROUND: The objective of this study was to determine the appropriate timing for surgical intervention for Grade II acute cholecystitis patients. The study compares the clinical outcomes of patients in Group A, who were treated with early laparoscopic cholecystectomy (ELC) within the first two weeks of hospitalization, and Group B, treated with delayed laparoscopic cholecystectomy (DLC) after recovering from symptoms and that received conservative treatment and were discharged for more than two weeks. METHODS: From November 2011 to June 2019, from a total of 196 acute cholecystitis patients that received percutaneous transhepatic gallbladder drainage (PTGBD) insertion, we conducted a retrospective review of the group that received early laparoscopic cholecystectomy within 2 weeks and the group that received delayed laparoscopic cholecystectomy. The clinical characteristics and post-treatment outcomes were evaluated. RESULTS: In all patients treated with PTGBD insertion, Group A, the patients who were treated with ELC, showed a significantly longer mean operative time than Group B, the patients who were treated with DLC (72.46 ± 46.396 vs. 54.08 ± 27.12, P = 0.001). Similarly, Group A showed a significantly longer postoperative hospital stay compared to Group B (5.71 ± 5.062 vs. 4.27 ± 2.931, P = 0.014). CONCLUSION: In patients with Grade II acute cholecystitis with PTGBD insertion, DLC produces better outcomes with shorter hospital stay and operative time than ELC. These results suggest that DLC may lead to a better outcome than ELC, specifically when deciding the timing for laparoscopic cholecystectomy in patients diagnosed with acute Grade II cholecystitis.

Effect of abdominal binder after laparoscopic cholecystectomy on enhanced recovery: a randomized controlled trial.

Purpose: The purpose of this randomized controlled trial was to compare the effects of abdominal binder after laparoscopic cholecystectomy. Methods: From August to December 2020, 66 patients who were set to undergo cholecystectomy were selected for a prospective trial at Kangbuk Samsung Hospital, Seoul, Republic of Korea, and their clinical characteristics and postoperative surgical outcomes were evaluated. Among 66 patients, 33 patients belong to the abdominal binder group and the other 33 patients belong to the control group. Results: The average hospital stay was 2.46 ± 1.29 days, and was not significantly different between the two groups. The average postoperative pain score (visual analogue scale, 0-10) 12, 24, and 48 hours after surgery were not significantly different. However, the degree of comfort score was significantly higher for the control group patients (2.56 vs. 3.33, p < 0.001). Time to the first ambulation, walking ability, return of bowel function, time to full diet resumption, and the numbers of analgesics and antiemetics administered were not significantly different between the two groups. Conclusion: No postoperative recovery benefit and no reduction in hospital stay was found in patients who used an abdominal binder while undergoing laparoscopic cholecystectomy. Statistically, between the group that used the binder and the one that did not, no significant differences in surgical outcome nor postoperative outcome were observed. The only exception was that the degree of comfort score was significantly higher in the control group. Therefore, in terms of patient benefit and convenience, wearing an abdominal binder after laparoscopic cholecystectomy is not recommended.

Safety of appendectomy during pregnancy in the totally laparoscopic age.

Purpose: Acute appendicitis is the most common nonobstetric indication for surgical intervention during pregnancy. In the argument of the optimal surgical approach to acute appendicitis in pregnancy, laparoscopy seems to be won with a similar complication rate and shorter postoperative recovery than open. We aimed to compare perioperative outcomes of appendectomy in pregnant and nonpregnant women in the totally laparoscopic age. Methods: We retrospectively analyzed 556 nonincidental appendectomies performed in women (aged 18-45 years) between January 2014 and December 2018. To reduce the confounding effects, we used propensity score considering the variables age, American Society of Anesthesiologists physical status classification, and the operative finding; whether the appendicitis was simple or complicated. After propensity score matching, the outcomes of 15 pregnant women were compared with those of the 30 nonpregnant women. Results: All the operations were performed with laparoscopy. Most of the pregnant cases were in their first and second trimester. The postoperative morbidity rate was significantly higher in the pregnant group before propensity score matching; however, the significance disappeared after matching. Operative outcomes and the parameters related to the postoperative recovery were not different between the two groups. Two patients in their first trimester decided to terminate the pregnancy after appendectomy. One patient in her second trimester experienced preterm labor which was resolved spontaneously. There was no other obstetric adverse outcome. Conclusion: In the laparoscopy age, appendectomy during pregnancy is safe and not associated with a significantly increased risk of postoperative complication.

Laparoscopic repair of inguinal hernias: Risk factors for urinary retention and chronic pain after totally extraperitoneal repair and transabdominal preperitoneal repair.

Purpose: There are various opinions about the postoperative complications of the two methods for laparoscopic inguinal hernia surgery; totally extraperitoneal repair (TEP) and transabdominal preperitoneal repair (TAPP). The aim of this study was to compare the postoperative course after TAPP and TEP, focusing on immediate postoperative pain, incidence of postoperative urinary retention (POUR), and chronic pain. Methods: This study retrospectively analyzed a consecutive series of 344 inguinal hernia patients who were treated with laparoscopic surgery between November 2016 and December 2019 at a single tertiary referral center. Results: Patient demographics did not differ significantly between the groups. The operation time was significantly shorter in the TEP group than in the TAPP group (43.1 ± 14.9 minutes vs. 63.5 ± 16.5 minutes, p < 0.001). The postoperative pain scores were significantly lower in the TEP group than in the TAPP group immediately (3.6 ± 1.3 vs. 4.4 ± 1.1, p < 0.001) and 6 hours (1.5 ± 1.4 vs. 2.3 ± 1.8, p < 0.001) after the operation. The other complications did not differ significantly between the groups. Age was a significant risk factor for POUR (odds ratio [OR], 1.083; 95% confidence interval [CI], 1.018-1.151; p = 0.011), and history of benign prostate hyperplasia (BPH) was a significant risk factor for chronic pain (OR, 5.363; 95% CI, 1.028-27.962; p = 0.046). Conclusion: TEP and TAPP seem to be safe and effective for laparoscopic inguinal hernia repair and have similar postoperative outcomes. Age was a significant risk factor for POUR, and BPH history was a significant risk factor for chronic pain.

An Unusual Case of Colon Perforation With Multiple Transmural Ulcers After Use of Polmacoxib and Everolimus in a Metastatic Breast Cancer Patient.

Everolimus (Afinitor) is an inhibitor of mammalian target of rapamycin. Polmacoxib (Acelex) is a nonsteroidal anti-inflammatory drug that belongs to the cyclooxygenase-2 (COX-2) inhibitor family and is mainly used for treatment of arthritis. Intestinal perforation has not been reported previously as a complication of everolimus, and perforation of the lower intestinal tract caused by a selective COX-2 inhibitor is extremely rare. We present here a case of colon perforation that occurred after use of polmacoxib in a metastatic breast cancer patient who had been treated with everolimus for the preceding six months.

Routine Intraoperative Bacterial Culture May Be Needed in Complicated Appendicitis.

PURPOSE: Choosing the appropriate antibiotic is important for treatment of complicated appendicitis. However, increasing multidrug resistant bacteria have been a serious problem for successful treatment. This study was designed to identify bacteria isolated from patients with complicated appendicitis and reveal their susceptibilities for antibiotics and their relationship with patient clinical course. METHODS: This study included patients diagnosed with complicated appendicitis and examined the bacterial cultures and antimicrobial susceptibilities of the isolates. Data were retrospectively collected from medical records of Kangbuk Samsung Hospital from January 2008 to February 2018. RESULTS: The common bacterial species cultured in complicated appendicitis were as follows: Escherichia coli (n=113, 48.9%), Streptococcus spp. (n=29, 12.6%), Pseudomonas spp. (n=23, 10.0%), Bacteriodes spp. (n=22, 9.5%), Klebsiella (n=11, 4.8%), and Enterococcus spp. (n=8, 3.5%). In antibiotics susceptibility testing, the positive rate of extended-spectrum beta lactamase (ESBL) was 9.1% (21 of 231). The resistance rate to carbapenem was 1.7% (4 of 231), while that to vancomycin was 0.4% (1 of 231). E. coli was 16.8% ESBL positive (19 of 113) and had 22.1% and 19.5% resistance rates to cefotaxime and ceftazidime, respectively. Inappropriate empirical antibiotic treatment (IEAT) occurred in 55 cases (31.8%) and was significantly related with organ/space surgical site infection (SSI) (7 of 55, P=0.005). CONCLUSION: The rate of antibiotic resistance organisms was high in community-acquired complicated appendicitis in Koreans. Additionally, IEAT in complicated appendicitis may lead to increased rates of SSI. Routine intraoperative culture in patients with complicated appendicitis may be an effective strategy for appropriate antibiotic regimen.