Wai-Keong Wong

Perforation of the Gastrointestinal Tract Secondary to Ingestion of Foreign Bodies

Ingesting a foreign body (FB) is not an uncommon occurrence. Most pass through the gastrointestinal (GI) tract uneventfully, and perforation is rare. The aim of this study was to report our experience with ingested FB perforations of the GI tract treated surgically at our institution. A total of 62 consecutive patients who underwent surgery for an ingested FB perforation of the GI tract between 1990 and 2005 were retrospectively reviewed. Three patients with no definite FB demonstrated intraoperatively were included. The patients had a median age of 58 years, and 37 (60%) were male. Of the 59 FBs recovered, 55 (93%) were toothpicks and dietary FBs such as fish bones or bone fragments. A definitive preoperative history of FB ingestion was obtained for only two patients, and 36 of 52 patients (69%) wore dentures. Altogether, 18 (29%) perforations occurred in the anus or distal rectum, and 44 perforations were intraabdominal, with the most common abdominal site being the distal ileum (39%). Patients with FB perforations in the stomach, duodenum, and large intestine were significantly more likely to be afebrile (P = 0.043), to have chronic symptoms (> 3 days) (P < 0.001), to have a normal total white blood cell count (P < 0.001), and to be asymptomatic or present with an abdominal mass or abscess (P < 0.001) compared to those with FB perforations in the jejunum and ileum. Ingested FB perforation in the adult population is most commonly secondary to unconscious accidental ingestion and is frequently caused by dietary FBs especially fish bones. A preoperative history of FB ingestion is thus rarely obtained, although wearing dentures is a common risk factor. FB perforations of the stomach, duodenum, and large intestine tend to present with a longer, more innocuous clinical picture than perforations in the jejunum or ileum.

Critical Appraisal of 232 Consecutive Distal Pancreatectomies With Emphasis on Risk Factors, Outcome, and Management of the Postoperative Pancreatic Fistula : A 21-Year Experience at a Single Institution

OBJECTIVE To critically analyze a large single-institution experience with distal pancreatectomy (DP), with particular attention to the risk factors, outcome, and management of the postoperative pancreatic fistula (PF). DESIGN Retrospective study. SETTING Tertiary referral center. PATIENTS A total of 232 consecutive patients with pancreatic or extrapancreatic disease necessitating DP over 21 years. INTERVENTIONS Twenty-one patients underwent spleen-preserving DP, 117 underwent DP with splenectomy, and 94 underwent DP with multiorgan resection. MAIN OUTCOME MEASURES The perioperative and postoperative data of patients who underwent DP were analyzed. This included factors associated with postoperative morbidity with particular attention to the PF (defined by the International Study Group of Pancreatic Fistula) and changing trends in operative and perioperative data during the study period. RESULTS The overall operative morbidity and mortality were 47% (107 patients) and 3% (7 patients), respectively. During the study period, the rates of resection increased from 3 cases to 23 per year, and increasingly these were performed for smaller and incidental lesions. The morbidity rate remained unchanged, but there was a decline in postoperative stay and the need for care in the intensive care unit. Pancreatic fistulas occurred in 72 patients (31%); 41 (18%) were grade A, 13 (6%) grade B, and 18 (8%) grade C. Increased weight, higher American Society of Anesthesiologists score, blood loss greater than 1 L, increased operation time, decreased albumin level, and sutured closure of the stump without main duct ligation were associated with a postoperative PF on univariate analysis. A DP with splenectomy was associated with a higher incidence of grade B or C PF and non-PF-related complications. Ninety-two percent of PFs were successfully managed nonoperatively. Clinical outcomes correlated well with PF grading, as evidenced by the progressive increase in outcome measures such as postoperative stay, readmissions, reoperations, radiologic interventions, and non-PF-related complications from grade A to C PFs. CONCLUSIONS Pancreatic fistula is the most common complication after DP and its incidence varies depending on the definition applied. Several risk factors for developing a PF were identified. Splenic preservation after DP is safe. The grade of a PF correlates well with clinical outcomes, and most PFs may be managed nonoperatively.

A review of mucinous cystic neoplasms of the pancreas defined by ovarian-type stroma: clinicopathological features of 344 patients.

Despite formal definitions of mucinous cystic neoplasms (MCNs) and intraductal papillary neoplasms (IPMNs) by the World Health Organization (WHO) and Armed Forces Institute of Pathology (AFIP), several controversies with regard to MCNs remain. The aim of this review was to determine the clinicopathological features of MCNs defined by ovarian-type stroma (OS) as proposed by the WHO and AFIP and to compare them with MCNs defined by less stringent criteria. A MEDLINE search was conducted to identify English-language articles on pancreatic MCNs from 1996 to 2005. Twenty-five studies were identified. The studies were divided into 2 groups: group A included 10 studies with 344 patients whereby the presence of OS was a criteria for the diagnosis of MCNs, and group B, included 15 studies comprising 761 patients whereby the presence of OS was not mandatory for the diagnosis of MCNs. Patients in group A (MCNs as defined by OS) were almost always female (99.7%), with a mean age of 47 (range, 18–95) years. MCNs were located predominantly in the body or tail of the pancreas (94.6%) and had a mean size of 8.7 cm (range, 0.6–35 cm); 76% were symptomatic, 6.8% demonstrated ductal communication, and 27% were malignant. At a mean follow-up of 57.5 (range, 1–264) months and 43 (range, 2–257) months after surgery, 97.9% of benign and 61.9% of malignant neoplasms were disease free, respectively. Patients in group B were older and had a higher proportion of males. Neoplasms were more evenly distributed in the pancreas, were smaller, communicated more frequently with the pancreatic duct, and were composed of a higher proportion of malignant tumors compared with group A. Their clinicopathological features were intermediate between those of group A and patients with IPMN. Pancreatic MCNs with OS have unique and distinct clinicopathological features. MCNs should be defined by the presence of OS, as it is the most reliable way of distinguishing MCNs from IPMN. Adoption of “looser” criteria will result in misclassification of some IPMNs as MCNs.

CT in the Preoperative Diagnosis of Fish Bone Perforation of the Gastrointestinal Tract

OBJECTIVE Foreign body perforation of the gastrointestinal (GI) tract has diverse clinical manifestations, and the correct preoperative diagnosis is seldom made. We report our experience with the use of CT in the preoperative diagnosis of fish bone perforation of the GI tract in seven patients. To our knowledge, this series is the largest to date addressing the role of CT in the diagnosis of fish bone perforation. CONCLUSION Clinical presentation and radiography are unreliable in the preoperative diagnosis of fish bone perforation of the GI tract. This limitation can be overcome with the use of CT, which is accurate in showing the offending fish bone. The accuracy of CT is limited by observer dependence. A high index of suspicion should always be maintained for the correct diagnosis to be made.

An Appraisal of Surgical and Percutaneous Drainage for Pyogenic Liver Abscesses Larger Than 5 cm

Objective:To determine whether first-line treatment with percutaneous or surgical drainage of liver abscesses larger than 5 cm results in better clinical outcome. Summary Background Data:Pyogenic liver abscesses larger than 5 cm are currently treated by intravenous antibiotics and either percutaneous (PD) or surgical drainage (SD). Percutaneous techniques have been increasingly performed in place of open drainage as first-line treatment. This paradigm shift has been fueled by the drive for low-risk and less-invasive procedures and the surgical option being reserved for percutaneous failures. Yet there is a lack of data to support percutaneous drainage over open surgical drainage as first-line treatment. Methods:Over a 3-year period, 80 patients with liver abscesses larger than 5 cm amenable to PD and SD were included in the study. This situation was possible as 1 team of surgeons favored the use of PD and 1 team favored the use of SD as first-line treatment. The treatment outcomes in both groups were compared, and clinical end-points included time to defervescence of fever, failure of treatment, secondary procedures, hospital stay, morbidity, and mortality. Results:PD was performed in 36 patients and SD in 44 patients as first-line treatment. Clinical, laboratory, and abscess parameters were comparable in both groups. Sixty-four of 80 patients (80%) had multiloculated abscess. The time to defervescence of fever was not statistically significant (PD versus SD, 4.85 versus 4.38 days; P = 0.09). However, SD had less treatment failures (3 versus 10, P = 0.013), less requirement for secondary procedures (5 versus 13, P = 0.01), and shorter length of hospital stay (8 versus 11 days, P = 0.03). There was no difference in morbidity or mortality rates. Conclusions:The results of our study show that for large liver abscesses more than 5 cm, SD provides better clinical outcomes than PD in terms of treatment success, number of secondary procedures, and hospital stay with comparable morbidity and mortality rates. SD should be considered as first-line treatment of large liver abscesses.

Outcome after surgical treatment of suspected gastrointestinal stromal tumors involving the duodenum: Is limited resection appropriate?

Present surgical opinion is divided regarding the optimal method for the treatment of duodenal gastrointestinal stromal tumor (GIST) with some supporting the selective use of limited resection (LR) versus others who prefer pancreaticoduodenectomy (PD).

Pancreatic Serous Oligocystic Adenomas: Clinicopathologic Features and a Comparison with Serous Microcystic Adenomas and Mucinous Cystic Neoplasms

The preoperative distinction between serous cystic neoplasms (SCNs) and mucinous cystic neoplasms (MCNs) is essential, as all MCNs are considered malignant or potentially malignant and should be surgically resected, whereas SCNs are almost always benign. However, the radiologic distinction between SCNs and MCNs is frequently difficult especially with serous oligocystic adenoma (SOA), a morphologic variant of SCN, as both SOA and MCN appear on cross-sectional imaging as a solitary macrocystic lesion in the pancreas. We reviewed all SOAs managed at our institution to determine if any clinicopathologic features would prove useful for establishing a preoperative diagnosis. Over a 15-year period, 64 patients with a pathologically confirmed diagnosis of a pancreatic cystadenoma or cystadenocarcinoma treated at Singapore General Hospital were retrospectively reviewed. There were 27 MCNs and 37 SCNs including 12 SOAs. In addition, 40 cases of SOA previously reported in the literature were reviewed and analyzed together with the 12 patients, making this a series of 52 SOAs. In our experience, SOAs comprised 32.4% of the SCNs, and females predominated (7/12). The median age of the patients was 42.5 years (range 22–74 years), and only 4 of the 12 patients were symptomatic. Most of the cysts were located in the body or tail of the pancreas (9/12), and the median cyst size was 52.5 mm (range 10–190 mm). When the clinicopathologic features of SOAs and serous microcystic adenomas (SMAs) were compared, there was no difference between the patients with SOAs and SMAs in terms of age, sex, presence of symptoms, cyst size, or site of the lesion. However, SOAs occurred in the women less frequently (67.3% vs. 96.3%, P = 0.004), were smaller [40 mm (range 10–190 mm) vs. 95 mm (range 25–180 mm), P < 0.001], and occurred more commonly in the head of the pancreas [25 (48.1%) vs. 2(7.4%)] compared to MCNs. None of the SOAs were frankly malignant compared to the 29.6% of MCNs that were. SOAs and SMAs have similar clinicopathologic features. On the other hand, SOAs differ from MCNs by their relatively higher male/female ratio, higher frequency of tumors occurring in the head of the pancreas, and smaller cyst size. Knowledge of these distinguishing clinical features when used in combination with other diagnostic modalities such as endoscopic ultrasonography/fine-needle aspiration will enable clinicians to better differentiate these two pathologic entities preoperatively.

Intra-abdominal and Retroperitoneal Lymphangiomas in Pediatric and Adult Patients

Intra-abdominal and retroperitoneal lymphangiomas are a rare, congenital malformations of the lymphatics, which are found predominantly in children. The aim of this study is to evaluate the clinical features of this tumor, highlighting the differences in adults and pediatric patients. We also evaluate the preoperative diagnosis, radiological features, surgical treatment, and outcome of this rare condition. Between 1990 and 2004, 14 patients who underwent surgical resection of an intra-abdominal lymphangioma were reviewed retrospectively. There were five pediatric patients between fetal age and 17 years of age and nine adults between 31 and 62 years of age. Overall, females outnumbered males in the series, with a male-to-female ratio of 3:4. However, males predominated in the pediatric age group with a male-to-female ratio of 1.5:1. The clinical presentation of children was more acute ranging from 3 days to 2 months. In adults, four patients were asymptomatic, and the remaining five had symptom duration ranging from 2 weeks to a year. The lymphangiomas occurred in the mesentery (n = 4), retroperitoneum (n = 4), omentum (n = 3), pancreas (n = 2), and spleen (n = 1). All the patients underwent total surgical resection with or without organ resection, and there were no recurrences at a median follow-up of 2 years (range; 3 months–13 years). This series demonstrates that abdominal lymphangiomas have a male preponderance and present more acutely in pediatric patients, whereas in adults, female patients predominate and the history is more chronic.

Predictive Factors of Malignancy in Adults with Intussusception

Adult intussusception is an unusual entity, and its etiology differs from that in pediatric patients. The aim of this study was to evaluate our experience of 60 adult patients with intussusception and determine if there are any preoperative factors predictive of malignancy. The records of 60 adult patients (> 18 years of age) with a diagnosis of intussusception surgically treated at Singapore General Hospital and Changi General Hospital between 1990 and 2004 were retrospectively reviewed. The intussusceptions were classified as enteric or colonic. Preoperative predictive factors of malignancy were analyzed using univariate and multivariate analyses, and P < 0.05 was considered statistically significant. There were 60 patients with a median age of 57.5 years (range 21–85 years). Altogether, 34 (56.7%) patients were male, and there were 31 enteric and 29 colonic intussusceptions. A lead point was identified in 54 patients (90%). A total of 22 (36.7%) patients presented with intestinal obstruction, and the correct preoperative diagnosis of intussusception was made in 31 patients (51.7%). Computed tomography was the most useful diagnostic modality, correctly identifying an intussusception in 24 of 30 patients. A malignant pathology was present in 8 of 31 (26%) enteric versus 20 of 29 (69%) colonic intussusceptions. Age (P = 0.009), the presence of anemia (P < 0.001), and the site of the intussusception (P = 0.001) showed significant differences between the benign and malignant groups by univariate analyses. On multivariate analysis, intussusception in the colon (P = 0.004) and the presence of anemia (P = 0.001) were independent predictive factors of malignancy. Adult intussusception is most commonly secondary to a pathologic lead point. The site of intussusception in the colon and the presence of anemia are independent preoperative predictors of malignancy. All colonic intussusceptions should be resected en bloc without reduction, whereas a more selective approach can be applied for enteric intussusceptions.

Evaluation of the Sendai and 2012 International Consensus Guidelines based on cross-sectional imaging findings performed for the initial triage of mucinous cystic lesions of the pancreas: a single institution experience with 114 surgically treated patients

BACKGROUND The Sendai Consensus Guidelines (SCG) were formulated in 2006 to guide the management of mucinous cystic lesions of the pancreas (CLPs) and were updated in 2012 (International Consensus Guidelines, ICG 2012). This study aims to evaluate the clinical utility of the ICG 2012 with the SCG based on initial cross-sectional imaging findings. METHODS One hundred fourteen patients with mucinous CLPs were reviewed and classified according to the ICG 2012 as high risk (HR(ICG2012)), worrisome (W(ICG2012)), and low risk (LR(ICG2012)), and according to the SCG as high risk (HR(SCG)) and low risk (LR(SCG)). RESULTS On univariate analysis, the presence of symptoms, obstructive jaundice, elevated serum carcinoembryonic antigen (CEA)/carbohydrate antigen (CA)19-9, solid component, main pancreatic duct ≥ 10 mm, and main pancreatic duct ≥ 5 mm was associated with high grade dysplasia/invasive carcinoma in all mucinous CLPs. Increasing number of HR(SCG) or HR(ICG2012) features was associated with a significantly increased likelihood of malignancy. The positive predictive value of HR(SCG) and HR(ICG2012) for high grade dysplasia/invasive carcinoma was 46% and 62.5% respectively. The negative predictive value of both LR(SCG) and LR(ICG2012) was 100%. CONCLUSION Both the guidelines were useful in the initial cross-sectional imaging evaluation of mucinous CLPs. The ICG 2012 guidelines were superior to the SCG guidelines.