Min-Hoe Chew

Postoperative serum methylation levels of TAC1 and SEPT9 are independent predictors of recurrence and survival of patients with colorectal cancer.

Serum carcinoembryonic antigen (CEA) is the only marker recommended for surveillance of colorectal cancer (CRC) recurrence; its sensitivity and specificity, however, are suboptimal. This study sought to evaluate the values of postoperative serum methylation levels of 7 genes for prognostication and especially for recurrence detection after curative resection.

Adenocarcinoma of the anal transitional zone after double stapled ileal pouch‐anal anastomosis for ulcerative colitis

The development of adenocarcinoma in the anal transitional zone, after restorative proctocolectomy for ulcerative colitis, is rare. We report the first Asian and sixth known case. A 41‐year‐old Indian lady had a long standing history of ulcerative colitis. Restorative proctocolectomy and stapled ileal pouch‐anal anastomosis without mucosectomy was performed. She remained asymptomatic until 3 years later when she complained of discomfort on defecation. A poorly differentiated adenocarcinoma in the anal transition zone was diagnosed and she subsequently underwent an abdomino‐perineal resection. The previously reported cases in the literature are reviewed. We also discuss the suggested surveillance for high‐risk patients who have undergone an ileal‐anal pouch anastomosis.

Phenotypic characteristics of hereditary non-polyposis colorectal cancer by the Amsterdam criteria: an Asian perspective.

Background:  Hereditary non‐polyposis colorectal cancer (HNPCC) is an autosomal disease with a 68–82% lifetime risk of colorectal cancer (CRC). This study examined the phenotypic characteristics of CRC in Amsterdam criteria‐positive Asian patients from the Singapore Polyposis Registry.

A prospective study assessing anal plug for containment of faecal soilage and incontinence

Objective  Faecal incontinence is a common and embarrassing problem for many individuals. Some patients remained symptomatic despite the availability of different treatments. There is a limited range of commercially available products designed to cope with faecal incontinence. The anal plug has been developed to contain the loss of stool. This study aimed to evaluate the use of anal plug in Asian patients with intractable faecal soilage and incontinence judged by clinical and functional outcomes.

The evaluation of CEEA 34 for stapled hemorrhoidectomy: results of a prospective clinical trial and patient satisfaction.

INTRODUCTION Stapled hemorrhoidectomy (SH) has routinely been performed using Procedure for Prolapse and Hemorrhoids Proximate Hemorrhoidal Circular Staplers (Ethicon Endo-surgery, Cincinnati, OH). Premium Plus CEEA 34 (Tyco Healthcare, New Haven, CT) has been recently introduced for SH. This study aims to review the effectiveness of CEEA 34 for SH. METHODS From April to June 2007, the SH procedure was performed or supervised by 5 experienced consultant surgeons. A quality of life telephone survey was performed within 4 to 6 weeks postoperatively. RESULTS Two hundred thirteen patients (52% men and 48% women) with a median age of 46 years (range 26-78 years) underwent SH during the trial period. Median duration of surgery was 10 minutes (range 5-35 minutes). Ninety-seven percent underwent SH for third- and fourth-degree piles. Ten patients (4.7%) had bleeding postoperatively in the first week that ceased with adrenaline injection or pack, and 2 required transfusions. Eighty-three percent participated in the quality of life survey, and 92% of these patients expressed satisfaction with the outcome of the procedure. CONCLUSION CEEA 34 for SH is safe and effective with few postoperative complications and high patient satisfaction.

Preliminary Results of Mismatch Repair Deficiency Screening via Immunohistochemical Staining in Young Asian Colorectal Cancers

Background: The incidence of mismatch repair (MMR) deficiency in young colorectal cancers (CRC) remains unknown in Asians. This preliminary study assessed the clinicopathological features and efficacy of screening for MMR protein deficiency in young Asian CRC patients. Methods: From January 2006 to October 2009, patients under the age of 50 with immunohistochemical (IHC) staining for MMR proteins in resected CRC specimens were retrieved from a prospective computerised database. Results: Eighty unrelated patients comprising predominantly 80% Chinese (n = 64), with median age of diagnosis at 41 years (range 22–50 years) had IHC performed. Twenty-three per cent (n=18) of the patients had abnormal IHC staining. Loss of staining for MLH1, MSH2 and MSH6 proteins were observed in 18%, 2% and 6% of tumours respectively. Of the 15 patients who had abnormal staining of MLH1, three had concomitant equivocal staining for MSH6. One tumour specimen had abnormal staining in all 3 proteins. Multivariate analysis revealed that family history was the only significant predictive factor for defective MMR detection (OR 8.06, 95% CI 1.69–38.35, p=0.002). However if Amsterdam criteria alone were to be used, 72% (n=12) of the cohort would have not been detected for MMR gene defects. Conclusion: The overall burden of germline MMR deficiency in the Singapore population may be as high as 23%. Amsterdam criteria alone are insufficient to detect hereditary non-polyposis colorectal cancer (HNPCC) related patients. The use of IHC staining of at least 3 MMR proteins is a useful screening strategy for HNPCC diagnosis and routine screening of mismatch repair deficiency may be recommended for all young Asian CRC patients.

The Use of CEEA 34 in Stapled Hemorrhoidectomy: Suggested Modifications in Technique

Stapled hemorrhoidectomy has been shown to be superior to conventional hemorrhoidectomy in numerous randomized, controlled trials and systemic reviews, with less postoperative pain and faster recovery. Premium Plus CEEA 34 has been recently introduced for use in stapled hemorrhoidectomy. The use of this stapler requires some modifications in technique.

Giant pseudopolyposis in Crohn's disease mimicking malignancy.

Dear editor, Giant pseudopolyposis or giant inflammatory polyposis consists of segmental, circumferential colonic lesions in inflammatory bowel disease and are extremely rare. We recently managed a patient who has a known history of Crohn’s disease but presented with a colonic stricture due to giant pseudopolyposis mimicking as a malignancy. A 26-year-old man presented to our department with an 8year history of Crohn’s disease. The disease initially involved mainly the ascending, transverse, and descending colon. He also had a concurrent fistula-in-ano andmouth ulcers. Medical treatment with steroids was instituted and the patient remained symptom free until 2 years ago when he developed recurrent flares of the disease. Surveillance colonoscopy revealed a sigmoid stricture and histology showed nonspecific regenerative changes. Barium enema revealed persistent sigmoid stricture with irregular mucosal pattern and multiple polyps (Fig. 1). As malignancy was not able to be excluded, a laparoscopic high-anterior resection was performed. The resected specimen measured 15 cm in length and contained an ulcerated narrow segment of bowel measuring 6.5 cm in length and 3.5 cm in width. There were multiple pedunculated polyps with the smallest polyp measuring 0.5 cm and the largest measuring 2 cm in maximum diameter (Fig. 2). Under microscopic examination, the surface of the polyps showed surface ulceration with a cap of fibrin. Stalks of these polyps were lined by glands of normal morphology. In the nonpolypoid areas of the colon, transmural inflammation with superficial ulceration together with granulomas and Int J Colorectal Dis (2008) 23:823–824 DOI 10.1007/s00384-008-0475-3

Prognostic Variables in 1814 Sporadic Colon Cancers: A Review of Experience from a Single Institution from 1999–2005

Introduction: Singapore has one of the highest age-standardized incidence rates for colorectal cancer (CRC) at 35.1% in men and 29.9% in women which is almost double that of our neighboring Southeast Asian countries. Surgery is presently the mainstay in treatment of this cancer. This present study evaluates the clinical and prognostic characteristics of sporadic cancers treated by surgical resection in a single institution in an Asian population. Methods: 1814 consecutive patients with CRC from 1999–2005 treated in the Department of Colorectal Surgery in Singapore General Hospital were reviewed. The clinciopathological characteristics of these patients were collected from a prospectively collected database maintained in the department since 1987. Univariate analysis was performed, and survival curves were constructed using the Kaplan-Meier method. Multivariate analysis was carried out on independent prognostic factors that were positive on univariate analysis. Results: All patients had a minimum follow up duration of 5 years unless they were lost to follow up. There were 921 (50.8%) males and 893 (49.2%) females with a median age of 67 years (interquartile range 22–99). The predominant location of the tumour was left-sided ie distal to (and including) the splenic flexure (n=1272, 70%), and the majority presented at an advanced AJCC stage III and IV (n=1018, 56%). The most common site for solitary metastasis is in the liver (n=194, 49%) followed by the lungs (6%). Locoregional recurrence is low at 2.6% (n=46) and distant recurrence is noted at 16.8% (n=297). Disease recurrence are 5.7%, 18.1%, and 27.5% for Stages I, II and III respectively. The median five-year Cancer Specific Survival (CSS) is 58.7 % (95% CI 56.2%–61.2%). On multivariate analysis, a high pre-operative CEA, poorly-differentiated tumour grade, signet ring cell tumours, high tumour stage (T3/T4), nodal disease (N1/N2), presence of both perineural invasion and vascular emboli were all significant factors that worsened CSS. Conclusion: Our dataset confirms the current favourable survival of colonic cancers in our country which is comparable to data from the West. Future challenges in management of patients involve improving staging, selection of high risk of recurrence of patients for closer monitoring and further adjuvant treatment to improve survival and reduce locoregional recurrence.