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Biomedical subjects

Chang Sik Yu

Publications and source records attributed to Chang Sik Yu.

17 recordsLinked to original sources

Tissue-derived extracellular matrix hydrogels instruct epigenetic adaptation in metastatic colonization.

The extracellular matrix (ECM) plays a central role in regulating tumor progression and metastatic colonization by providing biochemical and mechanical signals that shape cancer cell fate. However, most organoid culture systems rely on basement membrane extracts that fail to reproduce the tissue-specific extracellular environments encountered during metastasis. Here, we develop tissue-derived decellularized matrix hydrogels to reconstruct organ-specific microenvironments and investigate epigenetic adaptation to ECM cues during metastatic colonization. Patient-derived colorectal cancer organoids cultured in colon-derived matrices exhibited enhanced maintenance of stem-like phenotypes and colon-specific chromatin accessibility landscapes compared with cultures grown in basement membrane extracts, demonstrating improved physiological relevance for primary tumor modeling. When exposed to matrices derived from secondary organs, the organoids showed distinct growth phenotypes accompanied by rapid, tissue-dependent chromatin accessibility remodeling, indicating that ECM composition alone can reshape regulatory programs governing metastatic adaptation. Notably, liver-derived matrices selectively activated hepatocyte nuclear factor 4 alpha (HNF4A)-associated transcriptional networks and created a context-specific dependence on c-MET signaling for survival. Functional perturbation of HNF4A or c-MET signaling confirmed that both are required for organoid formation specifically within the liver matrix environment. Together, these findings establish tissue-derived matrix hydrogels as instructive bioactive materials that actively regulate cancer cell epigenetic states and reveal microenvironment-specific therapeutic vulnerabilities during early metastatic colonization.

Journal Article↗

Antitumor necrosis factor-alpha therapy for early postoperative recurrence of gastrointestinal Behçet's disease: report of a case.

Behçet's disease is a chronic, relapsing, systemic inflammatory disease characterized by recurrent oral and genital ulcers, skin lesions, and ocular lesions. Gastrointestinal tract is occasionally involved in Behçet's disease, and the typical gastrointestinal lesions are punched-out, discrete mucosal ulcerations. Corticosteroids, 5-aminosalicylic acid derivatives, thalidomide, and immunomodulators have been used to treat Behçet's disease. Some patients with gastrointestinal Behçet's disease undergo surgical management because of the refractoriness to these medical measures or complications, such as perforation and bleeding. Even after successful surgery, postoperative complications, such as poor healing of the anastomosis site and postoperative ulcer recurrence, are so common that repeated operations are frequently required. However, there have been few reports addressing the most effective way to reduce and treat postoperative complications and recurrences. We describe a patient with Behçet's disease involving the distal ileum, who was treated with infliximab as rescue therapy of an unhealed anastomosis site and early recurrent ulcers after a distal ileocecectomy because of persistent bleeding. Abdominal pain from recurrent ulcers improved by the fifth day after the infliximab infusion and almost disappeared by the second week. An ileocolonoscopy performed 15 days after the infliximab infusion showed near complete healing of the recurrent ulcers. This report suggests that infliximab may be an effective novel therapy for the management of early postoperative complications and recurrences in gastrointestinal Behçet's disease.

Antibodies, Monoclonal↗

Optimal time interval between capecitabine intake and radiotherapy in preoperative chemoradiation for locally advanced rectal cancer.

PURPOSE: Capecitabine and its metabolites reach peak plasma concentrations 1 to 2 hours after a single oral administration, and concentrations rapidly decrease thereafter. We performed a retrospective analysis to find the optimal time interval between capecitabine administration and radiotherapy for rectal cancer. METHODS AND MATERIALS: The time interval between capecitabine intake and radiotherapy was measured in patients who were treated with preoperative radiotherapy and concurrent capecitabine for rectal cancer. Patients were classified into the following groups. Group A1 included patients who took capecitabine 1 hour before radiotherapy, and Group B1 included all other patients. Group B1 was then subdivided into Group A2 (patients who took capecitabine 2 hours before radiotherapy) and Group B2. Group B2 was further divided into Group A3 and Group B3 with the same method. Total mesorectal excision was performed 6 weeks after completion of chemoradiation and the pathologic response was evaluated. RESULTS: A total of 200 patients were enrolled in this study. Pathologic examination showed that Group A1 had higher rates of complete regression of primary tumors in the rectum (23.5% vs. 9.6%, p = 0.01), good response (44.7% vs. 25.2%, p = 0.006), and lower T stages (p = 0.021) compared with Group B1; however, Groups A2 and A3 did not show any improvement compared with Groups B2 and B3. Multivariate analysis showed that increases in primary tumors in the rectum and good response were only significant when capecitabine was administered 1 hour before radiotherapy. CONCLUSION: In preoperative chemoradiotherapy for rectal cancer, the pathologic response could be improved by administering capecitabine 1 hour before radiotherapy.

Adult↗

A giant colonic hamartoma and multiple colonic hamartomatous polyps in a middle-aged man.

Colonic hamartomas are rare polypoid lesions. We report an unusual case of multiple colonic hamartomatous polyps, including a giant hamartoma, unrelated to hereditary or familial polyposis syndromes, in a 48-year-old man. The diameter of the largest polyp was 9.5 cm, and endoscopy revealed that the lesion caused colonic obstruction. The clinical, endoscopic and histological aspects of this case are discussed.

Colectomy↗

[Clinicopathologic characteristics of colorectal neuroendocrine tumor].

BACKGROUND/AIMS: Colorectal neuroendocrine carcinoma is a rare neoplasm exhibiting fulminant progression and having poor prognosis. The purpose of this study is to verify the clinicopathologic characteristics of colorectal neuroendocrine carcinoma. METHODS: From June 1997 to December 2004 at Asan Medical Center, ten patients were originally identified as colorectal neuroendocrine carcinoma on the basis of H&E and immunohistochemical staining (IHC). Carcinoid tumors were excluded in this study. Medical records of thirteen patients were reviewed retrospectively. RESULTS: Ten patients (0.2%) with colorectal neuroendocrine tumors were identified from 4,512 patients with colorectal cancer; ten neuroendocrine carcinomas and three adenocarcinomas with neuroendocrine differentiation. Their median age was 60 (41-83) years. The subjects consisted of six males and seven females. Nine tumors were located in the rectum, two in the sigmoid, and each one in the transverse colon and cecum, respectively. Nine of ten neuroendocrine carcinomas expressed synaptophysin, but chromogranin A were expressed in four. All patients were advanced at the time of diagnosis, with AJCC TNM staging: stage IIIB (n=2), stage IIIC (n=3), and stage IV (n=8). The median survival for ten neuroendocrine carcinomas and three adenocarcinomas with neuroendocrine differentiation were 16.4 months and 30 months, respectively. Five patients who received chemotherapy showed median survival of 32 months (stage III) and 17.5 months (stage IV), whereas other five patients without chemotherapy died with a median survival of 6.2 months. CONCLUSIONS: Colorectal neuroendocrine tumors are extremely rare showing aggressive behavior biologically, i.e fulminant early distant metastasis. Nevertheless, improved survival may be achieved by aggressive multimodality therapy.

Adenocarcinoma↗

Aberrant CpG island methylation in early-onset sporadic gastric carcinoma.

PURPOSE: Gastric carcinoma more commonly affects older patients, and it is thought that cases of early-onset gastric carcinoma may develop with a different molecular profile different from that of carcinoma occurring at a later age. We assayed the methylation status and genetic changes in genes associated with the APC-beta-catenin axis and the mismatch repair system in relatively early-onset gastric carcinoma samples to determine their association with gastric carcinogenesis. METHODS: Tumor and normal tissue DNA samples were obtained from 40 patients with early-onset (< 50 y) gastric carcinomas and assayed for APC and CTNNB1 mutations, microsatellite instability, and methylation of the promoters of the hMLH1, TIMP3, THBS1, DAP- K, GSTP1 , APC, and MINT2. RESULTS: Promoter methylation at these seven loci ranged from 12.5 to 62%, with 38/40 tumors (95%) showing promoter methylation at more than one locus. The CpG island methylation phenotype (CIMP) was classified as high in 16 tumors (40%), low in 22 tumors (55%), and negative in 2 tumors (5%). Two concurrent missense mutations (E1685G, R1763L) in the APC mutation cluster region were detected in two tumors, nine tumors showed loss of APC heterozygosity (LOH), and two showed both LOH and promoter methylation. CONCLUSIONS: Our results indicate that, unlike in colorectal carcinoma, APC and CTNNB1 mutations do not appear to be highly implicated in early-onset gastric carcinogenesis. In contrast, our data show that promoter methylation is a prevalent phenomenon in early-onset gastric carcinoma and may be related to gastric carcinogenesis.

Adaptor Proteins, Signal Transducing↗

Preoperative concurrent radiotherapy with capecitabine before total mesorectal excision in locally advanced rectal cancer.

PURPOSE: Capecitabine is an attractive radiosensitizer which can be tumor specific. This study was undertaken to evaluate the toxicity and efficacy of oral capecitabine when used with preoperative radiation therapy. METHODS AND MATERIALS: We conducted a prospective Phase II trial to assess the pathologic response, sphincter preservation effect, and acute toxicity of preoperative chemoradiation (CRT) in locally advanced (uT3-4/N +) but resectable adenocarcinoma of the lower two-thirds of the rectum. The radiation dose was 50 Gy over 5 weeks (46 Gy to whole pelvis + 4 Gy boost), and capecitabine was administered daily at a dose of 1650 mg/m(2) during the entire course of radiation therapy. Surgery was performed with standardized total mesorectal excision 4 to 6 weeks after completion of CRT and followed by four cycles of capecitabine (2500 mg/m(2)/day for 14 days). RESULTS: Ninety-five patients were entered into this study; their median age was 55 (range, 31-75 years). Ninety (95%) patients completed preoperative CRT as planned, and complete resection was achieved in 92 of 94 resected cases (98%). Downstaging rate was 71% (56/79) on endorectal ultrasonography, and it was 76% (71/94) on pathology finding. No tumor cell was observed in the specimens of 11 patients (12%). Among the 54 whose tumor was located within 5 cm from the anal verge, 40 patients (74%) underwent sphincter-preserving procedures. Elevation of the distal tumor margin from the anal verge by preoperative CRT was 0.8 +/- 1.3 cm. Grade 3 toxicities were rare (diarrhea in 3% and neutropenia in 1%). CONCLUSION: Preoperative CRT using capecitabine achieved encouraging rates of tumor downstaging and sphincter preservation with a low toxicity profile.

Adolescent↗

CpG island methylation as an early event during adenoma progression in carcinogenesis of sporadic colorectal cancer.

BACKGROUND AND AIMS: CpG island methylation is present in various tumors, including colorectal carcinomas, and is thought to be an important mechanism in carcinogenesis. We evaluated the methylation status of primary colorectal tumors to determine its role in the adenoma to carcinoma sequence. METHODS: The methylation status of APC, THBS1, MGMT, hMLH1 and GSTP1, as determined by methylation specific PCR (MSP), and microsatellite instability (MSI) using three mononucleotide markers were assessed in 40 colorectal adenomas and 36 adenocarcinomas. The correlations of methylation status and MSI with the clinicopathologic parameters of the tumors were determined. RESULTS: Of the 40 adenomas, 24 (60%) were methylated at one or more loci, and 12 (30%) at two or more loci (CpG island methylation phenotype-high, CIMP-H). Of 36 carcinomas, 27 (75%) were methylated at one or more loci and 11 (30.5%) at two or more loci (CIMP-H). THBSI was the most frequently methylated locus in both adenomas (n = 19, 47.5%) and carcinomas (n = 16, 44.4%). Overall, methylation status of adenomas and carcinomas did not differ significantly (P = 0.53), nor did the methylation status of individual genes. For adenomas, size (P = 0.049) and histologic classification of the villous components (P = 0.018) were each associated with methylation status. For carcinomas, however, no clinicopathologic variable was related to methylation status. MSI was detected in three adenomas (7.5%) and five carcinomas (13.9%), and was closely correlated with hMLH1 methylation (P < 0.001). CONCLUSIONS: In colorectal tumors, CpG island methylation of tumor suppressor genes appears to be common and may be involved in the progression of adenomas.

Adenocarcinoma↗

Cutoff values of preoperative s-CEA levels for predicting survivals after curative resection of colorectal cancer.

Serum carcinoembryonic antigen (s-CEA) is used to detect recurrence and predict prognosis in colorectal cancer. However, the cutoff values of s-CEA for prognosis have not been determined. We therefore tried to determine the preoperative s-CEA levels predictive of survivals in colorectal cancer patients. We retrospectively analyzed the medical records of 989 patients who underwent curative resection for colorectal cancer between July 1990 and December 1997, with a mean followup of 46 months (range, 3-129 months). When patients were divided into four subgroups with the cutoff values of s-CEA at 3,6, and 17 ng/mL, their 5-yr diseasefree survival rates were 85.3% (<3.0 ng/mL), 70.0% (3-6 ng/mL), 64.2% (6-17 ng/mL), and 55.2% (>17 ng/mL) (p<0.001). Multivariate analysis showed that factors predictive of survival included age (p=0.028), tumor stage (p<0.001), cell differentiation (p=0.016), and gross type (p=0.007), location (p=0.003) and preoperative s-CEA (p<0.001). Using the above-described cutoff levels, a significant difference in survival was observed only in patients with stage III tumors (p=0.007) when analyses were performed by stage. We can suggest the new cutoff values of s-CEA used in the present study.

Adult↗

[Analysis of pouchitis after restorative proctocolectomy].

BACKGROUND/AIMS: Pouchitis is one of the most common and debilitating complications of a restorative proctocolectomy. We aimed to analyze the features of pouchitis after restorative proctocolecomy and to determine the risk factors related to its development. METHODS: A study was undertaken in 169 patients who underwent total proctocolectomy with ileal pouch-anal anastomosis between July 1989 and December 2003. Pouchitis was defined as change of bowel habit, change in stool consistency, hematochezia or abdominal pain, febrile sensation and/or low-grade fever improved by metronidazole or ciprofloxacin without evidence of infectious disease and sphincter damage. RESULTS: Among the 169 patients, patients with ulcerative colitis were 64, familial and attenuated adenomatous polyposis 44, Crohn's disease 2, and synchronous or hereditary non-polyposis colorectal cancer were 59 cases. Overall, pouchitis occurred in 15.9% of the patients. The incidence was 37.5% in ulcerative colitis, 1% in non-ulcerative colitis, and 50% in Crohn's disease. In ulcerative colitis group, most of the pouchitis (60.9%) occurred within 6 months after the operation and the remainder experienced the first attack within 1 year after operation. Three patients progressed to chronic pouchitis. There was no association between pouchitis rate and sex, history of smoking, steroid use, temporary ileostomy construction, involvement of appendix or proximal colon, and evidence of indeterminate colitis. Only age was significantly related to the occurrence of pouchitis. CONCLUSIONS: Pouchitis developed exclusively in ulcerative colitis than other disease groups. Pouchitis occurred most frequently within 6 months after the operation, therefore, it is important to investigate carefully during one year after the operation in patients with ulcerative colitis.

Adenomatous Polyposis Coli↗

[Colonoscopic surveillance after curative resection for colorectal cancer with synchronous adenoma].

BACKGROUND/AIMS: Guidelines for current postoperative colonoscopic surveillance are not specified in colorectal cancer (CRC) patients with synchronous adenoma (SA). We performed this retrospective study to determine the postoperative colonoscopic surveillance interval for the CRC patients with SA. METHODS: One hundred and twenty-four CRC patients with SA (SA-group) and the same number of patients without SA (NSA-group) were selected from our database. Two groups were matched by the stage of CRC. Median colonoscopic surveillance period was 55 (12-99) months. The colonoscopic surveillance frequency and interval were similar between the two groups. RESULTS: Mean age was higher and male was more frequent in SA-group than NSA-group (p= 0.0001). The incidence of missed adenoma, advanced missed adenoma and metachronous adenoma (MA) were higher in SA-group (30.8% vs. 5.8% at 1st yr., p=0.0001; 4.4% vs. 0%, p=0.0001; 31.1% vs. 9.1% at 2nd yr., p=0.016) during the first consecutive two years of surveillance. The MA- and advanced-MA-free survival rate were lower in SA-group (24.6% vs. 6.6%, p=0.0001; 4.1% vs. 0%, p=0.02) during three years after surgery. Dysplasia of the SA (p=0.04; OR, 110.3; 95% CI, 1.13-10742.6) and presence of missed adenoma (p=0.036; OR, 43.6; 95% CI, 1.28-1490.1) were risk factors for the advanced MA on a multivariate analysis in SA-group. CONCLUSIONS: Postoperative colonoscopic surveillance at first year after surgery is warranted in CRC patients with SA.

Adenoma↗

Single-stage procedure with intraoperative colonoscopy and colonic irrigation in patients with obstructing left-sided colonic cancer.

BACKGROUND AND AIMS: Recently there has been growing acceptance of the one-stage resection and primary anastomosis with intraoperative antegrade irrigation. This study evaluated the efficacy of a newly developed device for performing a single-stage procedure in patients with obstructing left-sided colon cancer. PATIENTS AND METHODS: A series of 151 consecutive patients with obstructing left-sided colonic cancer underwent on-table irrigation, resection, and primary anastomosis with the use of a newly developed device; 75 patients on-table colonoscopy. The study spanned a 3 years from September 1999 to August 2002. The observed variables were the volume of irrigated saline, time for irrigation and colonoscopic examination, synchronous pathology, operative mortality and morbidity, time to passage of flatus, restarting day of oral intake, and length of hospital stay. RESULTS: The mean volume of irrigated saline was a mean of 12.5 l (range 1-32) over a mean of 14.2 min (range 1-45). Subsequent colonoscopic examination added a mean of 10.7 min (range 3-15). The incidence of synchronous polyps was 47% (35 of 75 cases) in performing the on-table colonoscopic investigations. On-table colonoscopy induced surgeons to extend resection because of synchronous malignancy attested by frozen biopsy specimen in ten patients and because of mucosal necrosis of the proximal colon in three. There were two anastomotic leakages, six wound infections, and one operative mortality. The time to passage of flatus was an average of 3.6 days (range 1.0-7). The time to oral intake was an average of 4.3 days (range 3-8). The length of hospital stay was 11.7 days (range 6-43). CONCLUSION: These findings suggest that our device is an effective tool to facilitate acceptance of the one-stage procedure in patients with obstructing left-sided colonic cancer. Specifically, our device enables quick and easy on-table colonoscopy.

Adult↗

Functional constipation with impaired rectal sensation improved by electrical stimulation therapy: report of a case.

Patients with intractable constipation often complain of social, physical, and psychologic stress. Recently, biofeedback therapy has been widely used for the management of intractable constipation, particularly in cases of constipation associated with pelvic floor dyssynergia. However, some constipated patients often complain of absent or diminished sense of wanting to defecate. It is unclear whether impaired rectal sensation is a cause or outcome of constipation and what specific treatment is available for these patients. We treated a 25-year-old female patient who complained of intractable constipation for ten years. Colon transit time study and defecography showed nonspecific findings. Her anorectal manometric findings were within normal ranges with the exception of impaired rectal sensation. Rectal sensory threshold volumes for desire and urge to defecate and maximal tolerated volume were greatly increased. She was treated by electric stimulation therapy for the purpose of improving impaired rectal sensory function. After 14 sessions of electric stimulation therapy, her constipated symptoms improved dramatically. Furthermore, the desire and urge threshold volumes were remarkably decreased. We report this case of constipation with impaired rectal sensation possibly treated by electric stimulation therapy.

Adult↗

Primary malignant melanoma of the rectum: CT findings in eight patients.

PURPOSE: To retrospectively evaluate computed tomographic (CT) findings in patients with pathologically proved primary malignant melanoma of the rectum. MATERIALS AND METHODS: CT scans of eight patients (three men and five women; age range, 38-74 years; mean age, 62 years) with histologically proved primary rectal malignant melanomas were retrospectively evaluated by two radiologists in consensus. Scans were evaluated for the involved site, approximate size and morphologic appearance of the primary mass, degree of perirectal infiltration, and presence or absence of lymphadenopathy, bowel obstruction, and distant metastases. RESULTS: All of the tumors were located in the distal rectum just above the anal verge. The approximate average sizes of the tumors were as follows: length, 4.8 cm (range, 3.8-6.9 cm); width, 3.8 cm (range, 2.8-5.2 cm); and mean diameter, 4.3 cm (range, 3.3-5.8 cm). Tumors usually appeared as polypoid or fungating intraluminal masses (n = 7). Perirectal infiltration commonly extended to the pelvic side wall or the presacral space (n = 5). All eight patients had lymphadenopathy, frequently larger than 3 cm in diameter (n = 3), which most commonly involved the perirectal lymph node station (n = 7). There was no evidence of bowel obstruction in any of the patients. Distant metastasis involving the liver was noted in one patient. CONCLUSION: On CT scans, primary rectal malignant melanomas appeared as bulky intraluminal fungating masses in the distal rectum, focally expanding and obscuring the lumen without causing obstruction, with perirectal infiltration and frequently enlarged lymph nodes.

Adult↗

[Should small bowel diverticula be removed?].

BACKGROUND/AIMS: Small bowel diverticulum is a rare disease that can be found incidentally during a surgical operation. Since reported complication rate is low, uncomplicated small bowel diverticula are generally recommended to be untreated. The aim of this study was to elucidate clinical features of this disease and to determine whether incidental small bowel diverticula should be removed for cure. METHODS: We reviewed the medical records of 80 patients with small bowel diverticular disease who underwent operation at Asan Medical Center between July 1989 and March 2003, retrospectively. RESULTS: Male to female ratio was 61:19, and the mean age was 44 (0-91) years. The most common diverticulum of small bowel is Meckel's diverticulum (63.8%), followed by duodenal diverticulum (15%), jejunal diverticulum (12.5%), and ileal diverticulum (8.7%). Of the 80 cases, 43 (53.7%) were symptomatic, and 37 (46.3%) were incidental. In the symptomatic patients, the most frequent symptom was abdominal pain (58.1%), followed by bleeding (44.2%). As for the treatments, segmental resection (53.7%) was performed more commonly than diverticulectomy (43.8%) in the symptomatic patients. Postoperative complications occurred more commonly in the symptomatic patients (25.6%) than the incidental patients (8.1%). Duodenal diverticula had a high morbidity and mortality rate. CONCLUSIONS: We should consider the diverticular disease of small bowel in patients with unexplained abdominal pain or gastrointestinal bleeding. As most small bowel diverticula, except for duodenal diverticula, are found incidentally and easily removed without postoperative morbidity or mortality, surgical resection appears to be recommended for the purpose of accurate diagnosis and treatment.

Adolescent↗

Clinicopathologic features of ileocolonic malignant lymphoma: analysis according to colonoscopic classification.

BACKGROUND: The aims of this study were to classify primary ileocolonic lymphomas according to colonoscopic findings and to determine the clinicopathologic relationship according to classes. METHODS: Thirty-two patients (22 men, 10 women; age range 29 to 75 years) with primary malignant lymphoma of the terminal ileum and/or colorectum were studied. The clinicopathologic features were evaluated according to colonoscopic findings. RESULTS: Thirty-six lesions in 32 patients were endoscopically classified as follows: fungating (14, 39%), ulcerofungating (11, 31%), infiltrative (5, 14%), ulceroinfiltrative (4, 11%), and ulcerative (2, 6%). Location of the lesions was as follows: terminal ileum, 15 (42%); colorectum, 14 (39%); both regions, 7 (19%). The most common histopathologic types were diffuse large cell (22, 69%) and large cell immunoblastic (5, 16%). There was no relationship between the endoscopic findings and histologic types. In 9 patients (28%), the clinical manifestation was intussusception, and all were found endoscopically to have the fungating type lesion. CONCLUSIONS: Primary ileocolonic lymphomas can be classified endoscopically into fungating, ulcerative, infiltrative, ulcerofungating, and ulceroinfiltrative types. Among these, fungating and ulcerofungating are the most frequent. Intussusception is a common clinical finding in ileocolonic lymphomas, occurring mainly in patients with the fungating type of lesion.

Colon↗

The role of colonoscopy in the diagnosis of appendicitis in patients with atypical presentations.

BACKGROUND: Acute appendicitis is one of the most common causes of acute abdomen. Despite recent advances in radiologic imaging, the diagnosis of acute appendicitis may be difficult on occasion. The aims of this study were to describe the colonoscopic features of appendicitis and to determine whether colonoscopy can be used as an adjunct for the diagnosis of appendicitis in patients with atypical presentations. METHODS: The colonoscopic findings in 21 patients (14 men, 7 women; average age 55 years) with a colonoscopic or histopathologic diagnosis of appendicitis were analyzed retrospectively. Colonoscopy was performed because diagnoses suggested by CT were other than acute appendicitis (11 patients), and/or the presenting clinical features were atypical for acute appendicitis with the duration of symptoms being 10 days or longer (17 patients). RESULTS: The colonoscopic diagnosis was acute appendicitis for all 21 patients. Seventeen underwent appendectomy, the diagnosis being verified in all cases. Of the 4 patients whose symptoms improved without appendectomy, 3 were considered to have acute appendicitis because pus was seen to drain from the appendiceal orifice at colonoscopy. A definite diagnosis could not be made in the remaining 1 patient. Therefore, the diagnosis of appendicitis was considered confirmed in 20 of 21 patients. Colonoscopic findings in these 20 patients included hyperemia (15) and bulging (18) at the appendiceal orifice area with surrounding mucosal edema (19), and drainage of pus from the appendiceal orifice (7). CONCLUSION: Colonoscopy may be useful in the diagnosis of appendicitis when the clinical presentation is atypical for appendicitis and/or imaging studies are nondiagnostic.

Abdomen, Acute↗