Early Prediction of Post-hepatectomy Liver Failure in Patients Undergoing Major Hepatectomy Using a PHLF Prognostic Nomogram.

BACKGROUND: Liver resection (LR) is the main modality of treatment for hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM). Post-hepatectomy liver failure (PHLF) remains the most dreaded complication. We aim to create a prognostic score for early risk stratification of patients undergoing LR. METHODOLOGY: Clinical and operative data of 472 patients between 2000 and 2016 with HCC or CRLM undergoing major hepatectomy were extracted and analysed from a prospectively maintained database. PHLF was defined using the 50-50 criteria. RESULTS: Liver cirrhosis and fatty liver were histologically confirmed in 35.6% and 53% of patients. 4.7% (n = 22) of patients had PHLF. A 90-day mortality was 5.1% (n = 24). Pre-operative albumin-bilirubin score (p = 0.0385), prothrombin time (p < 0.0001) and the natural logarithm of the ratio of post-operative day 1 to pre-operative serum bilirubin (SB) (ln(POD1Bil/pre-opBil); p < 0.0001) were significantly independent predictors of PHLF. The PHLF prognostic nomogram was developed using these factors with receiver operating curve showing area under curve of 0.88. Excellent sensitivity (94.7%) and specificity (95.7%) for the prediction of PHLF (50-50 criteria) were achieved at cut-offs of 9 and 11 points on this model. This score was also predictive of PHLF according to PeakBil > 7 and International Study Group for Liver Surgery criteria, intensive care unit admissions, length of stay, all complications, major complications, re-admissions and mortality (p < 0.05). CONCLUSIONS: The PHLF nomogram ( https://tinyurl.com/SGH-PHLF-Risk-Calculator ) can serve as a useful tool for early identification of patients at high risk of PHLF before the 'point of no return'. This allows enforcement of closer monitoring, timely intervention and mitigation of adverse outcomes.

Impact of the introduction of laparoscopic wedge resection as a surgical option for suspected small/medium-sized gastrointestinal stromal tumors of the stomach on perioperative and oncologic outcomes.

BACKGROUND: The present study is designed to determine the feasibility and impact of the introduction of laparoscopic wedge resection as a surgical option for the treatment of suspected small/medium-sized (<7 cm) gastric gastrointestinal stromal tumors (GISTs). METHODS: The study involved a retrospective review of 53 consecutive patients who underwent laparoscopic or open wedge resection of a suspected gastric GIST. It was divided into two consecutive time periods wherein laparoscopic resection was a surgical option only in the latter period. Comparisons were made between the outcomes of patients who underwent laparoscopic versus open wedge resection and the outcomes of patients treated during the two consecutive time periods (to determine the impact of the introduction of laparoscopic wedge resection), RESULTS: Fourteen patients (26%) underwent laparoscopic wedge resection with 1 conversion. The pathological exam showed that 41 patients (77%) had a GIST. Laparoscopic resection was significantly associated with a longer operative time, an earlier return of bowel function, earlier resumption of liquid and solid diet, decreased duration of parenteral or epidural analgesia use, and shorter postoperative hospitalization compared to open resection. There was no statistical difference in the rate of R1 resection and actuarial recurrence-free survival for the two approaches. Comparison between the two time periods demonstrated that the introduction of the laparoscopic approach in the latter period resulted in an earlier return of bowel function, earlier resumption of liquid and solid diet, and decreased duration of parenteral or epidural analgesia. CONCLUSIONS: Laparoscopic wedge resection for gastric GIST can be safely adopted. It is associated with a more favorable perioperative outcome than the open approach. Its introduction as a surgical option has resulted in an improvement in perioperative outcomes without compromising oncologic safety at our institution.

Which is the optimal risk stratification system for surgically treated localized primary GIST? Comparison of three contemporary prognostic criteria in 171 tumors and a proposal for a modified Armed Forces Institute of Pathology risk criteria.

BACKGROUND: This study aims to validate and compare the performance of the National Institute of Health (NIH) criteria, Huang modified NIH criteria, and Armed Forces Institute of Pathology (AFIP) risk criteria for gastrointestinal stromal tumors (GISTs) in a large series of localized primary GISTs surgically treated at a single institution to determine the ideal risk stratification system for GIST. METHODS: The clinicopathological features of 171 consecutive patients who underwent surgical resection for GISTs were retrospectively reviewed. Statistical analyses were performed to compare the prognostic value of the three risk criteria by analyzing the discriminatory ability linear trend, homogeneity, monotonicity of gradients, and Akaike information criteria. RESULTS: The median actuarial recurrence-free survival (RFS) for all 171 patients was 70%. On multivariate analyses, size >10 cm, mitotic count >5/50 high-power field, tumor necrosis, and serosal involvement were independent prognostic factors of RFS. All three risk criteria demonstrated a statistically significant difference in the recurrence rate, median actuarial RFS, actuarial 5-year RFS, and tumor-specific death across the different stages. Comparison of the various risk-stratification systems demonstrated that our proposed modified AFIP criteria had the best independent predictive value of RFS when compared with the other systems. CONCLUSION: The NIH, modified NIH, and AFIP criteria are useful in the prognostication of GIST, and the AFIP risk criteria provided the best prognostication among the three systems for primary localized GIST. However, remarkable prognostic heterogeneity exists in the AFIP high-risk category, and with our proposed modification, this system provides the most accurate prognostic information.

Outcome of distal pancreatectomy for pancreatic adenocarcinoma.

OBJECTIVES: To determine the outcome of patients undergoing distal pancreatectomy for pancreatic adenocarcinoma. METHODS: A retrospective review of 39 patients undergoing distal pancreatectomy for adenocarcinoma. RESULTS: Thirty patients underwent surgery for ductal adenocarcinoma, 5 for malignant intraductal papillary mucinous neoplasm and 4 for mucinous cystadenocarcinoma. Malignant cystic neoplasms were significantly less likely to demonstrate perineural invasion, more likely to be well-differentiated, of lower T stage and of lower AJCC staging compared to ductal adenocarcinoma. These had a longer median disease-specific survival (42 (3-144) vs. 15 (14-16) months, p = 0.002). Eight patients underwent extended resections. These were associated with longer operating times compared to standard resections but there was no difference in surgical morbidity or mortality, blood transfusions, length of hospitalization or long-term survival. Univariate analysis demonstrated that R2 resection, size >30 mm, lymph node involvement, need for perioperative blood transfusion, serum albumin <40 g/l and platelet count <200/microl were predictors of survival for ductal adenocarcinoma. CONCLUSIONS: Malignant cystic neoplasms have less aggressive behavior and more favorable outcome compared to ductal adenocarcinoma. R2 resection, larger tumor size, lymph node involvement, perioperative transfusion, decreased serum albumin and low platelet count are factors associated with decreased survival in patients with ductal adenocarcinoma undergoing distal pancreatectomy.

Predictors of post-hepatectomy liver failure in patients undergoing extensive liver resections for hepatocellular carcinoma.

BACKGROUNDS/AIMS: To determine the prevalence of post-hepatectomy liver failure/insufficiency (PHLF/I) in patients undergoing extensive hepatic resections for hepatocellular carcinoma (HCC) and to assess the predictive value of preoperative factors for post-hepatectomy liver failure or insufficiency (PHLF/I). METHODS: A retrospective review of patients who underwent liver resections for HCC between 2001 and 2013 was conducted. Preoperative parameters were assessed and analyzed for their predictive value of PHLF/I. Definitions used included the 50-50, International Study Group of Liver Surgery (ISGLS) and Memorial Sloan Kettering Cancer Centre (MSKCC) criteria. RESULTS: Among the 848 patients who underwent liver resections for HCC between 2001 and 2013, 157 underwent right hepatectomy (RH) and extended right hepatectomy (ERH). The prevalence of PHLF/I was 7%, 41% and 28% based on the 50-50, ISGLS and MSKCC criteria, respectively. There were no significant differences in PHLF/I between RH and ERH. Model for End-Stage Liver Disease (MELD) score and bilirubin were the strongest independent predictors of PHLF/I based on the 50-50 and ISGLS/MSKCC criteria, respectively. Predictive models were developed for each of the criteria with multiple logistic regression. CONCLUSIONS: MELD score, bilirubin, alpha-fetoprotein and platelet count showed significant predictive value for PHLF/I (all p<0.05). A composite score based on these factors serves as guideline for physicians to better select patients undergoing extensive resections to minimize PHLF.

A study into the risk of exacerbation of chronic hepatitis B after liver resection for hepatocellular carcinoma.

Liver resection is commonly performed for solitary hepatocellular carcinoma (HCC) in well-compensated cirrhotic and noncirrhotic patients. Data concerning exacerbation of chronic hepatitis B (ECHB) post-liver resection are scant. To determine the incidence, risk factors, and clinical outcomes of ECHB in patients who underwent hepatic resection for HCC. The methods consisted of a retrospective review of consecutive patients with chronic hepatitis B virus (HBV) infection who had undergone liver resection for HCC from January 2002 to December 2004. Seventy-seven patients underwent 82 liver resections; the mean age was 58.0 +/- 12.1 years; 87% male; 20% hepatitis B e-antigen positive. Incidence of all causes of postoperative hepatitis was 25.6% (n = 21), and ECHB was 8.5% (n = 7). Both groups had their peak alanine aminotransferases, 231.0 IU/L (74-1,400) and 312 IU/L (147-1,400), respectively, observed at day 84 postresection. Three patients died as a result of ECHB within 4 months postsurgery. One- and 2-year survival rates were poorest for the ECHB group at 42.9 and 21.4%, compared with those with postoperative hepatitis due to other causes at 60.3 and 45.2% and those without postoperative hepatitis at 87.7 and 73.5% (p < 0.001). Liver resection for HCC in patients with chronic HBV infection carries a risk for ECHB, and affected patients have poorer clinical outcomes. There is a need for close monitoring of these patients preoperatively and in the early postoperative period.

Positron emission tomography with 2-deoxy-2-[18f] fluoro-D-glucose in the detection of malignancy in intraductal papillary mucinous neoplasms of the pancreas.

A 79-year-old Indian male was admitted with upper abdominal discomfort of 1-year duration which was associated with loss of weight and appetite. Serum tumor markers, including carcinoembryonic antigen and carbohydrate antigen 19-9, were within normal limits. A computed tomographic scan demonstrated a cystically dilated and tortuous pancreatic duct measuring 1.9 cm, suggestive of an intraductal papillary mucinous neoplasm. Fusion positron emission tomography/computed tomography with 2-deoxy-2-[18F] fluoro-D-glucose positron emission tomography (FDG-PET/CT) which was subsequently performed confirmed a metabolically active focus within the pancreatic head mass with a standard uptake value (SUVmax) of 3.5 compatible with carcinoma. A total pancreatectomy was performed and the final histology demonstrated a main-duct type intraductal papillary mucinous neoplasm with a focus of high-grade dysplasia compatible with carcinoma-in-situ. These images illustrate the emerging utility of FDG-PET/CT in the preoperative detection of malignancy in intraductal papillary mucinous neoplasm.

Follicular dendritic cell sarcoma of the liver with metachronous small bowel and splenic metastases: a case report and literature review.

Follicular dendritic cell sarcoma (FDCS) of the liver is an extremely rare disease, accounting for a mere 0.4% of all soft tissue sarcomas. FDCS most commonly involves lymph nodes but also affects extranodal sites such as the gastrointestinal system, oral cavity, liver, spleen and pancreas, albeit less commonly. It is widely considered a low-to-intermediate grade malignancy. We report a case of FDCS with metachronous involvement of the liver, small intestines and spleen, its imaging, histological findings and its management.

Cystic lesions of the pancreas: an appraisal of an aggressive resectional policy adopted at a single institution during 15 years.

BACKGROUND: Although an aggressive resectional approach toward pancreatic cysts has been advocated in the past, many clinicians now deem this therapeutic strategy impractical given the rapidly increasing incidence of incidentally detected pancreatic cystic lesions. The aim of this study was to review the aggressive resectional policy toward pancreatic cysts adopted at our institution during the past 15 years. METHODS: One hundred nine consecutive patients who underwent surgical resection of a cystic lesion of the pancreas during a 15-year period were retrospectively reviewed. To determine subsets of patients at lower risk of having a malignant cyst, the clinicopathologic features (in particular, the malignant potential) of these patients were compared as a function of 3 variables, ie, presence of symptoms, patient age, and cyst size, using univariate analyses. Results were expressed as median and range and P < .05 was considered statistically significant. RESULTS: Forty-three (39%) of 109 patients were asymptomatic. Incidental cysts were smaller (28 [10 to 240] vs 59 [10 to 200] mm, P < .001) and were found in older patients (55.0 [18 to 77] vs 45.5 [14 to 82] years, P = .003). Overall, 14% of asymptomatic cysts, versus 35% of symptomatic cysts, were malignant (P = .016). Incidental cysts were also less likely to be premalignant or malignant compared with symptomatic cysts (47% vs 70%, P = .015). Twenty (18%) patients were elderly (73.0 [70 to 82] years old). Elderly patients had a more equal sex distribution (45% vs 76% female, P = .005) and had smaller cysts (26 [10 to 200] vs 55 [10 to 240] mm, P = .003) that involved the head of the pancreas more frequently (8 [40%] vs 17 [19%], P = .045) compared with their younger counterparts. The cohort of elderly patients also had a higher median American Society of Anesthesiologists score (2 [1 to 3] vs 1 [1 to 3], P < .001), and a higher proportion had undergone a "more" major procedure (Whipple's or total pancreatectomy) (55% vs 18%, P < .001). Not unexpectedly, surgical morbidity in the elderly was significantly higher (10 [50%] vs 24 [27%], P = .045). The operative mortality in both groups was not significantly different (1 [5%] vs 1 [1%], P = .324). The proportion of premalignant or malignant lesions in elderly patients was also similar to that in younger patients (11 [55%] vs 55 [62%], P = .574). The size of a cyst in asymptomatic patients had no correlation with its potential for malignancy. CONCLUSIONS: Reliance on preoperative characteristics alone such as the presence of symptoms, cyst size, and patient age are not sufficiently reliable in determining the malignant potential and thus management approach toward pancreatic cysts.

Retroperitoneal schwannoma.

BACKGROUND: Retroperitoneal schwannomas are rare, benign tumors. The aim of this study is to present our surgical experience with 7 such tumors. METHODS: Between 1989 and 2004, 7 patients with pathologically proven retroperitoneal schwannomas were reviewed retrospectively. RESULTS: There were 6 male patients and 1 female patient, with a mean age of 43 years (range, 23 to 58 years). Two patients were symptomatic and presented with abdominal discomfort, and none of the patients suffered from von Recklinghausen's disease. All the patients underwent computed tomography scanning, which showed a heterogenous retroperitoneal mass, 4 of which were thought to arise from the adrenals. In 2 patients, calcification was seen in the tumors. All 7 of the patients had a preoperative diagnosis of a retroperitoneal tumor including 3 patients who were thought to have adrenal neoplasms (1 patient had a diagnosis of an adrenal neoplasm excluded on magnetic resonance imaging). Laparotomy and complete excision of tumors were performed in all the patients, and there was no morbidity or mortality. The schwannomas had a mean maximum diameter of 7.3 cm (range, 4 to 14 cm), and they were all benign. At a mean follow-up of 17 months (range, 3 to 48 months) postresection, all the patients remained free from recurrence. CONCLUSION: Retroperitoneal schwannomas are rare tumors that are difficult to diagnose preoperatively. Radiologic findings are usually nondiagnostic. The treatment of choice is complete surgical excision.

Non-neoplastic cystic and cystic-like lesions of the pancreas: may mimic pancreatic cystic neoplasms.

BACKGROUND: Cystic lesions of the pancreas consist of a broad range of pathological entities. With the exception of the pancreatic pseudocyst, these are usually caused by pancreatic cystic neoplasms. Non-neoplastic pancreatic cystic and cystic-like lesions are extremely rare. In the present article, the surgical experience with these unusual entities over a 14-year period is reported. METHODS: Between 1991 and 2004, all patients who underwent surgical exploration for a cystic lesion of the pancreas were retrospectively reviewed. Patients with a pancreatic pseudocyst were excluded. There were 106 patients of whom 8 (7.5%) had a final pathological diagnosis consistent with a non-neoplastic pancreatic cystic or cystic-like lesion, including 3 patients with a benign epithelial cyst, 2 with a pancreatic abscess (one tuberculous and one foreign body), 2 with mucous retention cysts and 1 with a mucinous non-neoplastic cyst. These eight patients are the focus of this study. RESULTS: There were six female and two male patients with a median age of 61.5 years (range, 41-71 years). All the patients were of Asian origin including seven Chinese and one Indian. Four of the patients were asymptomatic and their pancreatic cysts were discovered incidentally on radiological imaging for other indications. All the patients underwent preoperative radiological investigations, including ultrasonography, computed tomography or magnetic resonance imaging, which showed a cystic lesion of the pancreas. Three patients, all of whom were symptomatic, were diagnosed preoperatively with a malignant cystic neoplasm on the basis of radiological imaging. Two patients were eventually found to have a pancreatic abscess, one tuberculous and the other, secondary to foreign body perforation. The third patient was found on final histology to have chronic pancreatitis with retention cysts. The remaining five patients had a preoperative diagnosis of an indeterminate cyst; on pathological examination, they were found to have a benign epithelial (congenital) cyst (n = 3), retention cyst (n = 1) and mucinous non-neoplastic cyst (n = 1). At a median follow up of 20 months (range, 3-34 months), none of the patients had any evidence of recurrent disease. CONCLUSION: Non-neoplastic cystic and cystic-like lesions of the pancreas are rare causes of pancreatic cystic lesions that are generally benign and do not require surgery when asymptomatic. However, despite advances in diagnostic investigations such as endoscopic ultrasound with fluid aspirate and magnetic resonance imaging, the preoperative diagnosis remains unreliable. Hence, the challenge for all clinicians is to recognize these lesions preoperatively and to avoid 'unnecessary' surgery.

Utility of fusion CT-PET in the diagnosis of small pancreatic carcinoma.

Pancreatic carcinoma has a poor prognosis and early detection is essential for potentially curative resection. Despite the wide array of diagnostic tools, preoperative detection of small pancreatic carcinomas remains difficult. We report a case of small pancreatic carcinoma of the head of pancreas with indeterminate findings on US, ERCP, MRI and EUS which was successfully diagnosed via fusion CT-PET. This case illustrates the utility of CT-PET in the diagnosis of patients with small pancreatic carcinoma with equivocal findings on conventional diagnostic modalities.

On developing a pragmatic strategy for clinical trials: A case study of hepatocellular carcinoma.

Randomised controlled trials (RCTs) with sufficiently high statistical power are not always feasible for patients when the administration of the treatment is burdensome. Nevertheless, useful information concerning the relative effectiveness of the Test and Standard therapies, may be gleaned from under powered trials, non-randomised comparative studies and/or clinician's beliefs: the latter possibly additionally providing some suggestion of the strength of evidence required in order to adopt the Test therapy into clinical practice. In such circumstances, a Bayesian synthesis may be useful in quantifying the evidence of treatment effectiveness. In this article, we aim to present a Bayesian approach for synthesizing the cumulative evidence of the use of adjuvant hepatic intra-arterial iodine-131-lipiodol (I131L) following curative resection in hepatocellular carcinoma (HCC) patients. We constructed a posterior distribution using the information from two small RCTs, three non-randomised comparative studies, three single arm studies and the views of investigators on the use of I131L. This distribution enables calculation of the probability that the Test therapy is more effective than the Standard by a pre-stipulated amount. If this is very high, then for example, one may conclude the Test may replace the Standard therapy. If it is not, then the Standard would be retained for clinical use. Despite a strong early indication of the effectiveness of I131L, the evolving evidence over a 10-year period became more sceptical of its value. Although highly recommended, difficulties of implementing a Bayesian approach in this context are highlighted.

Biliary-enteric transanastomotic stenting with Intestofix.

BACKGROUND: Biliary-enteric transanastomotic stenting is useful under adverse local conditions or when small-calibre bile ducts are encountered. METHODS: A commercially available feeding jejunostomy kit, Intestofix, was inserted transjejunally through the blind loop of a Roux-en-Y hepatico-jejunostomy. CONCLUSIONS: The stent splinted the anastomosis to reduce biliary leaks and may help to prevent subsequent stricture formation.

Surgical management of endoscopic retrograde cholangiopancreatography-related perforations.

BACKGROUND: A retrospective review was carried out of consecutive cases of endoscopic retrograde cholangiopancreatography (ERCP)-related perforation to identify risk factors and technique affecting surgical outcome. METHODS: Eighteen patients (0.45%) out of 4030 ERCP performed were operated on for ERCP-related perforation at Singapore General Hospital. RESULTS: The group's median age was 72.5 years and 14 patients had ductal stone disease. Five perforations were discovered at ERCP while 10 required computed tomography for diagnosis. Eight patients were operated on within 24 h whereas 10 patients had surgery after 24 h. Five of six with type I (lateral duodenal) perforations had early surgery versus one of seven with type II (peri-Vaterian; P = 0.03). There were four type III (bile duct) perforations and one type IV (retroperitoneal air). Five of six patients with type I perforation had simple repair compared with five of seven type II requiring the complex duodenal diversion procedure (P = 0.10). Three patients (16.7%) succumbed after surgery due to sepsis and myocardial infarction. Advanced age>70 years resulted in higher mortality of 30% versus none in patients <70 years (P = 0.22). CONCLUSIONS: Early diagnosis is important but difficult especially for the type II perforations. Duodenal diversion is used more frequently in patients with type II perforations and those operated on late. Advanced age contributes to poorer outcome in surgical treatment of ERCP perforations.

Rectal arterio-portal fistula: an unusual cause of persistent bleeding per rectum following a proximal spleno-renal shunt.

Gastrointestinal arterio-venous malformations are a known cause of gastrointestinal bleeding. We present a rare case of persistent rectal bleeding due to a rectal arterio-portal venous fistula in the setting of portal hypertension secondary to portal vein thrombosis. The portal hypertension was initially surgically treated with splenectomy and a proximal splenorenal shunt. However, rectal bleeding persisted even after surgery, presenting us with a diagnostic dilemma. The patient was re-evaluated with a computed tomography mesenteric angiogram which revealed a rectal arterio-portal fistula. Arterio-portal fistulas are a known but rare cause of portal hypertension, and possibly the underlying cause of continued rectal bleeding in this case. This was successfully treated using angiographic localization and super-selective embolization of the rectal arterio-portal venous fistula via the right internal iliac artery.The patient subsequently went on to have a full term pregnancy. Through this case report, we hope to highlight awareness of this unusual condition, discuss the diagnostic workup and our management approach.

Validation of five contemporary prognostication systems for primary pancreatic endocrine neoplasms: results from a single institution experience with 61 surgically treated cases.

BACKGROUND: Presently, several systems for the prognostication of pancreatic endocrine neoplasms (PENs) exist and the most appropriate classification system has not been clearly defined. This study aims to validate the performance of the 2004 World Health Organization (WHO), European Neuroendocrine Tumor Society (ENETS), Memorial Sloan-Kettering Cancer Center (MSKCC), American Joint Committee for Cancer (AJCC) TNM staging and Bilimoria criteria in a cohort of patients with PENs who underwent surgery at a single institution. METHODS: This study is a retrospective review of 61 consecutive patients who underwent surgical treatment for PEN. Actuarial disease-specific survival (DSS) of all 61 patients and recurrence-free survival (RFS) of 53 patients who had curative resection were analysed. RESULTS: On univariate analyses, tumour size ≥50 mm, non-curative resection, lymph node involvement, presence of distant metastases, presence of necrosis, mitotic count ≥2/10 hpf and poor differentiation were associated with decreased DSS. Tumour size ≥50 mm, lymph node involvement, lymphovascular invasion, presence of necrosis and mitotic count ≥2/10 hpf were associated with decreased actuarial RFS. All five staging systems were useful in stratifying the 61 patients according to actuarial DSS. However, the MSKCC grading and ENETS grading systems were not statistically significant in stratifying DSS in the 61 patients. In the 53 patients who underwent curative resection, the WHO, ENETS, MSKCC, AJCC staging and the MSKCC grading systems were successful in stratifying the patients according to actuarial RFS. However, the Bilimoria scoring and ENETS grading systems were not useful in prognosticating these 53 patients. CONCLUSION: All five classification systems were useful for the prognostication of surgically treated PENs in our patient cohort.

Outcome after curative resection of large (>or=10 cm) gastric gastrointestinal stromal tumors: how frequent is adjacent organ involvement and is concomitant distal pancreatectomy necessary?

INTRODUCTION: Complete tumor resection with clear margins including adjacent organs is the treatment of choice for gastrointestinal stromal tumors (GISTs). However, true tumor invasion of adjacent organs has been reported to be rare. Concomitant distal pancreatectomy (DP) for suspected tumor infiltration is not infrequently performed during resection of large gastric GISTs. This study aims to determine the true frequency of adjacent organ involvement by large gastric GISTs with particular attention to the pancreas and compares the outcome after curative resection with and without a concomitant DP in order to determine if DP is truly necessary. METHODS: A retrospective review of 37 patients who underwent curative resection of large (>or=10 cm) gastric GISTs was conducted. RESULTS: Wedge resections were performed in 22, partial gastectomies in nine, and total gastrectomies in six patients. The median operative time was 180 min (range, 60-330 min), and the patients had a median postoperative stay of 8 days (range, 4-29 days). Overall, there were eight (22%) morbidities including two (5%) mortalities. Nineteen (51%) had concomitant adjacent organ resection, and these included 15 (41%) DPs with splenectomies. Direct organ invasion was demonstrated in 5/19 patients (26%) and 7/30 organs (23%) resected. Only 1/15 (6.7%) DP specimens demonstrated tumor infiltration. Comparison between the patients with and without a concomitant DP demonstrated that performance of a DP was associated with a longer operation time [225 min (range, 105-305 min) vs 158 min (60-330 min), P=.002)], increased postoperative stay [9 days (range, 7-29 days) vs 7.5 days (4-19 days), P=.042], and increased postoperative morbidity [6 (40%) vs 2 (9%), P=.025]. The DP cohort also had a statistically significant poorer 5-year recurrence free survival (22% vs 60%, P=.017). CONCLUSION: Although adjacent organ involvement is not uncommon with large gastric GISTs, concomitant DP is usually unnecessary as direct pancreatic invasion is rare. Furthermore, concomitant DP with splenectomy is associated with an increase in postoperative morbidity.

Ampullary carcinoma: effect of preoperative biliary drainage on surgical outcome.

AIM: To evaluate the influence of preoperative biliary drainage on morbidity and mortality after surgical resection for ampullary carcinoma. METHODS: We analyzed retrospectively data for 82 patients who underwent potentially curative surgery for ampullary carcinoma between September 1993 and July 2007 at the Singapore General Hospital, a tertiary referral hospital. Diagnosis of ampullary carcinoma was confirmed histologically. Thirty-five patients underwent preoperative biliary drainage (PBD group), and 47 were not drained (non-PBD group). The mode of biliary drainage was endoscopic retrograde cholangiopancreatography (n = 33) or percutaneous biliary drainage (n = 2). The following parameters were analyzed: wound infection, intra-abdominal abscess, intra-abdominal or gastrointestinal bleeding, septicemia, biliary or pancreatic leakage, pancreatitis, gastroparesis, and re-operation rate. Mortality was assessed at 30 d (hospital mortality) and also long-term. The statistical endpoint of this study was patient survival after surgery. RESULTS: The groups were well matched for demographic criteria, clinical presentation and operative characteristics, except for lower hemoglobin in the non-PBD group (10.9 +/- 1.6 vs 11.8 +/- 1.6 in the PBD group). Of the parameters assessing postoperative morbidity, incidence of wound infection was significantly less in the PBD than the non-PBD group [1 (2.9%) vs 12 (25.5%)]. However, the rest of the parameters did not differ significantly between the groups, i.e. sepsis [10 (28.6%) vs 14 (29.8%)], intra-abdominal bleeding [1 (2.9%) vs 5 (10.6%)], intra-abdominal abscess [1 (2.9%) vs 8 (17%)], gastrointestinal bleeding [3 (8.6%) vs 5 (10.6%)], pancreatic leakage [2 (5.7%) vs 3 (6.4%)], biliary leakage [2 (5.7%) vs 3 (6.4%)], pancreatitis [2 (5.7%) vs 2 (4.3%)], gastroparesis [6 (17.1%) vs 10 (21.3%)], need for blood transfusion [10 (28.6%) vs 17 (36.2%)] and re-operation rate [1 (2.9%) vs 5 (10.6%)]. There was no early mortality in either group. Median survival was 44 mo (95% CI: 34.2-53.8) in the PBD group and 41 mo (95% CI: 27.7-54.3; P = 0.86) in the non-PBD group. CONCLUSION: Biliary drainage before surgery for ampullary cancer significantly reduced postoperative wound infection. Overall mortality was not influenced by preoperative drainage.

A single-institution experience with eight CD117-positive primary extragastrointestinal stromal tumors: critical appraisal and a comparison with their gastrointestinal counterparts.

INTRODUCTION: Gastrointestinal stromal tumors (GISTs) arising from outside the gut wall also termed extragastrointestinal stromal tumors (EGISTs) are reported to be rare. Presently, their pathogenesis remains controversial, and recently, it has been proposed that EGISTs may be the result of extensive extramural growth of GISTs which lose contact with the gut wall. This study presents a single-institution experience with eight EGISTs and compares their clinicopathological features with mural GISTs in order to determine further insight to their possible origin. METHODS: Between 1997 and 2008, 156 patients with pathologically proven CD117-positive primary GISTs were retrospectively reviewed. Eight tumors were identified as EGISTs, 104 were gastric GISTs, and 44 were small-bowel GISTs. Mural GISTs were classified as extramural or intra/transmural according to their gross pattern of growth. RESULTS: There were five male and three female patients with a median age of 58 years (range, 42-81 years). All patients were symptomatic, and the tumors were located in the greater omentum (n = 2), lesser sac (n = 2), lesser omentum, retroperitoneum, small-bowel mesentery, and pancreas. The median tumor size was 140 mm (range, 55 to 220 mm). Seven of eight EGISTs were found to be in close association to the adjacent gut wall. Pathological examination demonstrated that two tumors demonstrated focal involvement of the muscularis propria of the adjacent gut wall. Four tumors demonstrated tumor abutting or adherent to the serosa but no muscle involvement and one tumor was separated from the serosa. Comparison between the clinicopathological features of EGISTs with extramural GISTs and intra/transmural GISTs demonstrated that EGISTs were significantly larger [140 range (55-220) mm vs 80 (5-260) mm vs 50 (15-190) mm, P = 0.049, P < 0.001 respectively]. CONCLUSION: The occurrence of true EGISTs is rare. Most cases demonstrate some form of communication or contact with the gut wall, and EGISTs are significantly larger than extramural or intra/transmural GIST. These observations suggest that most, if not all, cases of EGISTs are likely to represent mural GISTs with extensive extramural growth with eventual loss of contact with the muscle layer of the gut.