Sang Hui Moon

Endoscopic submucosal dissection for rectal neuroendocrine (carcinoid) tumors.

PURPOSE Rectal neuroendocrine (carcinoid) tumors smaller than 1 cm without lymph node metastasis and confined within the submucosal layer (stage T1aN0) can be treated using endoscopic resection. The present study was aimed to assess the safety and efficacy of endoscopic submucosal dissection (ESD) for T1aN0 carcinoid tumors. PATIENTS AND METHODS A total of 35 consecutive patients with a T1aN0 rectal carcinoid tumor were enrolled between March 2007 and December 2009. The study evaluated the histologically complete resection rate, procedure time, complications, and short-term oncological outcomes. RESULTS The mean patient age was 49.0 years (range, 32-74 years), and there were 25 men and 10 women. The mean procedure time was 35.6 minutes (range, 7-82 minutes). All neoplasms were removed in one piece, and the histologically complete resection rate was 74.3% (26 cases including 5 cases showing no residual tumor). No post-ESD bleeding was observed. Abdominal computed tomography scans showed a perforation in 1 patient only, but that perforation was not associated with any peritonitis symptoms, and the patient was discharged on postprocedure day 3. One patient underwent radical surgery after ESD because of angiolymphatic invasion and positive resection margins, and the final pathology revealed no residual tumor or lymph node metastasis. No patient showed local recurrence or distant metastasis during a median follow-up of 25 months (range, 12-43 months). CONCLUSIONS ESD is feasible and safe for treating T1aN0 rectal carcinoid tumors. Further studies are required to accurately determine long-term oncological outcomes.

Rectourethral Fistula: Systemic Review of and Experiences With Various Surgical Treatment Methods

Purpose A rectourethral fistula (RUF) is an uncommon complication resulting from surgery, radiation or trauma. Although various surgical procedures for the treatment of an RUF have been described, none has gained acceptance as the procedure of choice. The aim of this study was to review our experience with surgical management of RUF. Methods The outcomes of 6 male patients (mean age, 51 years) with an RUF who were operated on by a single surgeon between May 2005 and July 2012 were assessed. Results The causes of the RUF were iatrogenic in four cases (two after radiation therapy for rectal cancer, one after brachytherapy for prostate cancer, and one after surgery for a bladder stone) and traumatic in two cases. Fecal diversion was the initial treatment in five patients. In one patient, fecal diversion was performed simultaneously with definitive repair. Four patients underwent staged repair after a mean of 12 months. Rectal advancement flaps were done for simple, small fistula (n = 2), and flap interpositions (gracilis muscle flap, n = 2; omental flap, n = 1) were done for complex or recurrent fistulae. Urinary strictures and incontinence were observed in patients after gracilis muscle flap interposition, but they were resolved with simple treatments. The mean follow-up period was 28 months, and closure of the fistula was achieved in all five patients (100%) who underwent definitive repairs. The fistula persisted in one patient who refused further definitive surgery after receiving only a fecal diversion. Conclusion Depending on the severity and the recurrence status of RUF, a relatively simple rectal advancement flap repair or a more complex gracilis muscle or omental flap interposition can be used to achieve closure of the fistula.

Favorable surgical treatment outcomes for chronic constipation with features of colonic pseudo-obstruction

AIM To determine long-term outcomes of surgical treatments for patients with constipation and features of colonic pseudo-obstruction. METHODS Consecutive 42 patients who underwent surgery for chronic constipation within the last 13 years were prospectively collected. We identified a subgroup with colonic pseudo-obstruction (CPO) features, with dilatation of the colon proximal to the narrowed transitional zone, in contrast to typical slow-transit constipation (STC), without any dilated colonic segments. The outcomes of surgical treatments for chronic constipation with features of CPO were analyzed and compared with outcomes for STC. RESULTS Of the 42 patients who underwent surgery for constipation, 33 patients had CPO with dilatation of the colon proximal to the narrowed transitional zone. There were 16 males and 17 females with a mean age of 51.2 ± 16.1 years. All had symptoms of chronic intestinal obstruction, including abdominal distension, pain, nausea, or vomiting, and the mean duration of symptoms was 67 mo (range: 6-252 mo). Preoperative defecation frequency was 1.5 ± 0.6 times/wk (range: 1-2 times/wk). Thirty-two patients underwent total colectomy, and one patient underwent diverting transverse colostomy. There was no surgery-related mortality. Postoperative histologic examination showed hypoganglionosis or agangliosis in 23 patients and hypoganglionosis combined with visceral neuropathy or myopathy in 10 patients. In contrast, histology of STC group revealed intestinal neuronal dysplasia type B (n = 6) and visceral myopathy (n = 3). Early postoperative complications developed in six patients with CPO; wound infection (n = 3), paralytic ileus (n = 2), and intraabdominal abscess (n = 1). Defecation frequencies 3 mo after surgery improved to 4.2 ± 3.2 times/d (range: 1-15 times/d). Long-term follow-up (median: 39.7 mo) was available in 32 patients; all patients had improvements in constipation symptoms, but two patients needed intermittent medication for management of diarrhea. All 32 patients had distinct improvements in constipation symptoms (with a mean bowel frequency of 3.3 ± 1.3 times/d), social activities, and body mass index (20.5 kg/m(2) to 22.1 kg/m(2)) and were satisfied with the results of their surgical treatment. In comparison with nine patients who underwent colectomy for STC without colon dilatation, those in the CPO group had a lower incidence of small bowel obstructions (0% vs 55.6%, P < 0.01) and less difficulty with long-distance travel (6.7% vs 66.7%, P = 0.007) on long-term follow-up. CONCLUSION Chronic constipation patients with features of CPO caused by narrowed transitional zone in the left colon had favorable outcomes after total colectomy.

Can the new American Joint Committee on Cancer staging system predict survival in rectal cancer patients treated with curative surgery following preoperative chemoradiotherapy

Although ypStage has been known as a strong prognosticator of recurrence and survival, the detailed interaction of ypT and ypN classification on a survival rate has never been evaluated.

Surgical management of colonic diverticular disease: Discrepancy between right- and left-sided diseases

AIM To compare the outcome of the surgical management of left-sided and right-sided diverticular disease. METHODS The medical records of 77 patients who were surgically treated for diverticular disease between 1999 and 2010 in a tertiary referral hospital were retrospectively reviewed. The study population was limited to cases wherein the surgical specimen was confirmed as diverticulosis by pathology. Right-sided diverticula were classified as those arising from the cecum, ascending colon, and transverse colon, and those from the descending colon, sigmoid colon, and rectum were classified as left-sided diverticulosis. To assess the changing trend of occurrence of diverticulosis, data were compared with two previous studies of 51 patients. RESULTS The proportion of left-sided disease cases was significantly increased compared to the results of our previous studies in 1994 and 2001, (27.5% vs 48.1%, P < 0.05). Moreover, no differences in gender, body mass index, multiplicity of the diverticula, fever, or leukocytosis were noted between patients with right-sided and left-sided disease. However, patients with right-sided disease were significantly younger (50.9 year vs 64.0 year, P < 0.01). Furthermore, left-sided disease was significantly associated with a higher incidence of complicated diverticulitis (89.2% vs 57.5%, P < 0.01), combined resection due to extensive inflammation (21.6% vs 5.0%, P < 0.05), operative complications (51.4% vs 27.5%, P < 0.05), and in-hospital mortality (10.8% vs 0%, P < 0.05), along with longer post-operative hospitalization duration (21.3 ± 10.2 d vs 10.6 ± 8.1 d, P < 0.05). CONCLUSION Compared with right-sided diverticular disease, the incidence of left-sided disease in Korea has increased since 2001 and is associated with worse surgical outcomes.

Colonoscopic Surveillance after Colorectal Cancer Resection: Who Needs More Intensive Follow-Up?

Background/Aims: Although there are guidelines for colonoscopic surveillance after colorectal cancer (CRC) surgery, the data evaluating the effectiveness of these guidelines are limited. We determined the risk factors for metachronous neoplasia (MN) by performing annual colonoscopy examinations after curative resection. Methods: We performed annual colonoscopic surveillance on stage I-III CRC patients after curative resection. We stratified the patients based on the advanced neoplasia risk during the surveillance. Results: Advanced MN detected was in 59 (13.1%) of 451 patients. Overall, the cumulative incidence of advanced MN was 17.3% at 5 years. By the multivariate analysis, the risk factors for advanced MN were male gender, age >65, left-sided index cancer and being in the high-risk group. The cumulative incidence of advanced MN was 38.9% at 5 years in the high-risk group. Among the patients who had advanced MN, secondary advanced MN was detected in 13 patients (22.0%) with a subsequent colonoscopy. The 2-year cumulative incidence of secondary advanced MN was 16.9%. Four (0.88%) patients had metachronous CRC during the surveillance and the interval from the index CRC was a median of 58.5 months. Conclusions: Although the current follow-up guidelines for colonoscopic surveillance after CRC are well established, the high-risk group calls for more meticulous follow-up, which should be continued for a sufficient time.

Complications after ileal pouch-anal anastomosis in Korean patients with ulcerative colitis

AIM To investigate the outcomes of treatments for complications after ileal pouch-anal anastomosis (IPAA) in Korean patients with ulcerative colitis. METHODS Between March 1998 and February 2013, 72 patients (28 male and 44 female, median age 43.0 years ± 14.0 years) underwent total proctocolectomy with IPAA. The study cohort was registered prospectively and analyzed retrospectively. Patient characteristics, medical management histories, operative findings, pathology reports and postoperative clinical courses, including early postoperative and late complications and their treatments, were reviewed from a medical record system. All of the ileal pouches were J-pouch and were performed with either the double-stapling technique (n = 69) or a hand-sewn (n = 3) technique. RESULTS Thirty-one (43.1%) patients had early complications, with 12 (16.7%) patients with complications related to the pouch. Pouch bleeding, pelvic abscesses and anastomosis ruptures were managed conservatively. Patients with pelvic abscesses were treated with surgical drainage. Twenty-seven (38.0%) patients had late complications during the follow-up period (82.5 ± 50.8 mo), with 21 (29.6%) patients with complications related to the pouch. Treatment for pouchitis included antibiotics or anti-inflammatory drugs. Pouch-vaginal fistulas, perianal abscesses or fistulas and anastomosis strictures were treated surgically. Pouch failure developed in two patients (2.8%). Analyses showed that an emergency operation was a significant risk factor for early pouch-related complications compared to elective procedures (55.6% vs 11.1%, P < 0.05). Pouchitis was related to early (35.3%) and the other late pouch-related complications (41.2%) (P < 0.05). The complications did not have an effect on pouch failure nor pouch function. CONCLUSION The complications following IPAA can be treated successfully. Favorable long-term outcomes were achieved with a lower pouch failure rate than reported in Western patients.

The effects of eupatilin (stillen®) on motility of human lower gastrointestinal tracts.

Gastrointestinal motility consists of phasic slow-wave contractions and the migrating motor complex (MMC). Eupatilin (Stillen®) has been widely used to treat gastritis and peptic ulcers, and various cytokines and neuropeptides are thought to be involved, which can affect gastrointestinal motility. We performed a study to identify the effects of eupatilin on lower gastrointestinal motility with electromechanical recordings of smooth muscles in the human ileum and colon. Ileum and colon samples were obtained from patients undergoing bowel resection. The tissues were immediately stored in oxygenated Krebs-Ringers bicarbonate solution, and conventional microelectrode recordings from muscle cells and tension recordings from muscle strips and ileal or colonic segments were performed. Eupatilin was perfused into the tissue chamber, and changes in membrane potentials and contractions were measured. Hyperpolarization of resting membrane potential (RMP) was observed after administration of eupatilin. The amplitude, AUC, and frequency of tension recordings from circular and longitudinal smooth muscle strips and bowel segments of the ileum and colon were significantly decreased after admission of eupatilin. Eupatilin elicited dose-dependent decreases during segmental tension recordings. In conclusion, eupatilin (Stillen®) showed inhibitory effects on the human ileum and colon. We propose that this drug may be useful for treating diseases that increase bowel motility, but further studies are necessary.

Long-term Outcomes and Risk Factors for Reoperation After Surgical Treatment for Gastrointestinal Crohn Disease According to Anti-tumor Necrosis Factor-α Antibody Use: 35 Years of Experience at a Single Institute in Korea

Purpose Crohn disease is characterized by high rates of recurrence and reoperations. However, few studies have investigated long-term surgical outcomes in Asian populations. We investigated risk factors for reoperation, particularly those associated with anti-tumor necrosis factor-α (anti-TNF-α) antibody use, and long-term follow-up results. Methods We reviewed the records of 148 patients (100 males and 48 females) who underwent surgery for gastrointestinal Crohn disease and retrospectively analyzed long-term outcomes and risk factors. Results The mean age at diagnosis was 28.8 years. Thirty-eight patients (25.7%) received monoclonal antibody treatment before reoperation. A small bowel and colon resection was most commonly performed (83 patients, 56.1%). The median follow-up was 149 months, during which 47 patients underwent reoperation. The median interval between the primary and the secondary surgeries was 65 months, with accumulated reoperation rates of 16.5%, 31.8%, and 57.2% after 5, 10, and 15 years, respectively. Obstruction was the most common indication for reoperation (37 patients, 25.0%). In a multivariable analysis, age <17 years at diagnosis (A1) (odds ratio [OR], 2.20; P = 0.023), penetrating behavior (B3) (OR, 4.39; P < 0.001), and no azathioprine use (OR, 2.87; P = 0.003) were associated with reoperation. Anti-TNF-α antibody use did not affect the reoperation rate (P = 0.767). Conclusion We showed a high reoperation rate regardless of treatment with anti-TNF-α antibody, which indicates that recurrent surgery is still needed to cure patients with gastrointestinal Crohn diseases. Younger age at primary operation, penetrating behavior, and no azathioprine use were significant factors associated with reoperation for gastrointestinal Crohn disease.

Prognostic Impact of Changes in Adipose Tissue Areas after Colectomy in Colorectal Cancer Patients

There have been few studies assessing the changes in the body components of patients after colectomy in colorectal cancer (CRC). The purpose of this study was to verify the trends in the adipose tissue areas of CRC patients before and after surgery and to determine their clinical relevance. Computed tomography (CT)-assessed subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) areas were recorded before and after curative resection in stage I to III CRC patients. Changes in the adipose tissue were assessed by calculating the difference in the adipose tissue area between preoperative CT and the most recent postoperative CT, which is disease-free state. Regarding obesity before surgery, there were no prognostic effect of body mass index (BMI), VAT and SAT, and 47.3% of patients had increases in VAT after colectomy. By multivariate analysis, adjusting sex, age, stage, differentiation, VAT change was the only obesity related factor to predict the prognosis, that patients who had increase in VAT after colectomy had better overall survival (HR, 0.557; 95% CI, 0.317-0.880) and disease-free survival (HR, 0.602; 95% CI, 0.391-0.927). BMI and SAT change had no significant association. In subgroup analysis of stage III CRC patients, VAT change had significance for prognosis only in patients who had adjuvant chemotherapy but not in those who did not receive postoperative chemotherapy. Increase in visceral adipose tissue after surgery is a favorable predictor of prognosis for CRC patients.