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Elijah Dixon

Publications and source records attributed to Elijah Dixon.

At least 19 recordsLinked to original sources
PubMed2006

Autoimmune pancreatitis associated with renal lesions mimicking metastatic tumours.

Autoimmune pancreatitis is a chronic inflammatory disorder that is often misdiagnosed as pancreatic cancer. Since autoimmune pancreatitis is benign and responds to steroid management, it is important to diagnose it to avoid unnecessary surgical intervention. We describe a novel case of IgG4-associated autoimmune pancreatitis presenting with tubulointerstitial nephritis as renal lesions mimicking metastatic tumours but with no change in renal function.

Autoimmune Diseases↗
PubMed2006

Complex hepatic surgery aided by a 1.5-tesla moveable magnetic resonance imaging system.

BACKGROUND: Resection represents the best treatment for potentially curable liver tumors; radiofrequency ablation (RFA) is an alternative. The curative potential of RFA may be hampered because the extent of burn is difficult to estimate by ultrasound. We postulated that intraoperative MRI (iMRI) would enable a more accurate assessment of ablation completeness. METHODS: We performed open hepatic surgery in an operating room equipped with a unique, retractable 1.5-T magnet. Patients were selected because it was anticipated that RFA (with or instead of resection) was likelihood and that iMRI might be helpful in making intraoperative decisions. After baseline MRI, lesions were further assessed by ultrasound at the time of open surgery. Lesions were resected and/or ablated, and further imaging confirmed the margins of the procedure. RESULTS: Nine patients underwent the procedure: 1 with metastatic carcinoid, 4 with hepatocellular carcinoma, and 4 with colorectal liver metastases. In 4 patients, iMRI had an effect on decision-making. In 5 individuals, there were nonlocal recurrences, and 1 patient who was never disease-free had a local recurrence. COMMENTS: Intraoperative MRI could potentially impact operative decision-making when ablating extensive disease. Its ability to prevent local recurrences must be determined. Moreover, the role of this technology in the overall treatment armamentarium must be defined.

Carcinoma↗
PubMed2005

Factors associated with early recurrence after resection for hepatocellular carcinoma and outcomes.

BACKGROUND: Early recurrence (ER) (<1 year) after liver resection is one of the most important factors that impact the prognosis of patients with hepatocellular carcinoma (HCC). We sought to determine factors associated with ER of HCC and examine the outcomes thereafter. STUDY DESIGN: From March 2001 to June 2003, 56 patients underwent hepatic resection for HCC at University of Toronto and were prospectively followed with median followup of 24 months. Patients with ER were compared with those who remained disease free for more than 1 year. Patient characteristics, tumor stage, and operative procedures were evaluated for their prognostic significance by univariate and multivariable analysis. Time to recurrence and time to death were analyzed using Kaplan-Meier survival curves and compared using log-rank analysis. RESULTS: The initial procedure in all patients was surgical hepatectomy. ER occurred in 21 patients (38%), 31 (55%) remained disease free for more than 1 year, and 4 (7%) were omitted from evaluation because of early (<30 days) death. Median survival after initial hepatic resection for those with ER was 27 months, and 2-year survival was 54%. There were no deaths in the group that remained disease free for more than 1 year (100% 2-year survival, p < 0.05). By multivariate analysis, vascular invasion and positive microscopic margins were significant predictors when all 4 variables were considered in the model (p < 0.05). After ER, 11 of 21 patients (52%) underwent additional therapy with significant improvement in median survival (33 months) compared with those not eligible for conventional therapy (18 months, p = 0.05). CONCLUSIONS: ER after liver resection for HCC is the leading cause of death during the first 2 years after potentially curative resection. ER will develop in approximately 75% of patients with either vascular invasion or positive margins. For patients with these predictive factors additional treatment might be advised.

Adult↗
PubMed2005

Transduodenal resection of peri-ampullary lesions.

Transduodenal resection (TDR) of lesions near the ampulla of Vater is an alternative to the Whipple pancreaticoduodenectomy. A retrospective analysis was performed to determine the long-term outcome and the utility of intraoperative frozen section examinations in aiding operative decision making in patients undergoing TDR. From 1992 to 2002, 19 patients with an average age of 64.2 years (range: 33-84 years) underwent a transduodenal resection of a peri-ampullary lesion; median follow-up was 47 months (range: 2-100 months). Pathology of the lesions was as follows: 11 with benign ampullary adenomas, including 4 with familial adenomatous polyposis (FAP); 7 with peri-ampullary adenocarcinomas; and 1 with a benign stricture. Survival for the entire cohort is 100%. In 12 cases an intraoperative frozen section was performed. The specificity and positive predictive value of the intraoperative histology were both 100%, and the sensitivity and negative predictive value were 57% and 38%, respectively. Three of the 4 patients with FAP have recurrent adenomatous change; 2 of the 7 with carcinoma have metastatic adenocarcinoma. Transduodenal resection of peri-ampullary lesions appears to be a safe alternative to radical resection for benign adenomas and selected carcinoma. Intraoperative frozen section assessment is recommended in cases of potential adenocarcinoma.

Adenocarcinoma↗
PubMed2005

Vascular occlusion to decrease blood loss during hepatic resection.

BACKGROUND: Historically, the primary hazard with liver surgery has been intraoperative blood loss. This led to the refinement of inflow and outflow occlusive techniques. The utility of the different methods of inflow and outflow techniques for hepatic surgery were reviewed. METHODS: A search of the English literature (Medline, Embase, Cochrane library, Cochrane clinical trials registry, hand searches, and bibliographic reviews) using the terms "liver," "hepatic," "Pringle," "total vascular exclusion," "ischemia," "reperfusion," "inflow," and "outflow occlusion" was performed. RESULTS: A multitude of techniques to minimize blood loss during hepatic resection have been studied. The evidence suggests that inflow occlusion techniques are generally well tolerated. These should be used with caution in patients with cirrhosis, fibrosis, steatosis, cholestasis, and recent chemotherapy, and for prolonged time intervals. CONCLUSIONS: Harmful effects of intraoperative blood loss and transfusion occur during hepatic resection. Portal triad clamping (PTC) is associated with less blood loss compared with no clamping. In procedures with ischemic times <1 hour in length, PTC-C (continuous) is likely equal to PTC-I (intermittent). In patients with chronic liver disease or undergoing lengthy operations, PTC-I is likely superior to PTC-C. PTC is superior to total vascular exclusion except in patients with tumors that are large and deep seated, hypervascular, and/or abutting the hepatic veins or vena cava and in patients with increased right-sided heart pressures.

Blood Loss, Surgical↗
PubMed2005

Extramucosal hepaticojejunostomy.

BACKGROUND: The creation of a secure hepaticojejunostomy is an essential skill for any hepatobiliary surgeon. METHODS: We describe a refined technique of sewing the end of the common hepatic duct to the side of the jejunum. The sutures are placed to include all layers of the bowel wall except mucosa. RESULTS: One hundred eighty-five anastomoses were performed over a 6-year period. There were 3 documented leaks, 1 significant anastomotic bleed, and 2 postoperative strictures. There were no deaths. CONCLUSION: This refined technique facilitates accurate placement of sutures by improving vision and results in a well-vascularized watertight connection.

Anastomosis, Surgical↗
PubMed2005

Training, practice, and referral patterns in hepatobiliary and pancreatic surgery: survey of general surgeons.

Subspecialization has changed the way that general surgery is practiced. Hepatobiliary and pancreatic surgery (HPB) is maturing as a subspecialty. The objective of this study was to identify the current levels of practice, self-assessments of adequacy of training, referral patterns, and perceptions regarding regionalization of HPB care to high-volume centers. A total of 240 nonstratified general surgeons from across Canada were randomly selected to receive a survey developed by an expert work group. A reference group of 10 HPB specialists were also polled for a total of 250 respondents. The overall response rate was 73% (182 responders). Subspecialty training had been completed by 65% of respondents. This included surgical oncology (15%), HPB (15%), HPB and transplant (8%), laparoscopy (7%), liver transplantation (5%), and other (50%). This training was obtained in Canada (51%), the United States (35%), Europe (11%), and Australia (3%). Ninety-five percent of responders believed that some HPB services should be regionalized. Similarly, most responders thought that they were not adequately trained to perform these procedures. The following were especially considered subspecialty procedures: major hepatectomy (93%), pancreaticoduodenectomy (90%), and biliary reconstruction (79%). The majority of non-HPB surgeons do not consider themselves adequately trained to perform complex HPB procedures. Furthermore, most surgeons think that major hepatectomy, pancreaticoduodenectomy, and biliary reconstruction should be referred to HPB specialists at high-volume centers.

Adult↗
PubMed2005

Hepatic arterial infusion after curative resection of colorectal cancer metastases: a meta-analysis of prospective clinical trials.

The use of hepatic arterial infusion (HAI) for the delivery of chemotherapeutic agents to treat residual microscopic disease after curative hepatic resection for colorectal cancer metastases remains controversial. In recent years, a number of studies examining adjuvant HAI have shown conflicting results. A meta-analysis of prospective clinical trials was performed to determine if adjuvant HAI confers a survival benefit in this setting. Two reviewers independently performed a literature search of MEDLINE, PubMed, EMBASE, the Cochrane library, and the Cochrane Clinical Trials Registry. Prospective clinical trials comparing hepatic arterial chemotherapy after curative hepatic resection for colorectal cancer metastases against a control arm were included. Non-English-language publications were excluded. The outcome measure was survival difference at 1 and 2 years after surgery. Seven studies met the inclusion criteria, and all except one were randomized trials. The survival difference in months (positive values favoring the treatment arm) was 1.8 at 1 year (95% confidence interval, -4.9, 8.5) and 9.6 at 2 years (95% confidence interval, -2.2, 21.4). Neither was statistically significant (at 2 years, P=0.11). Based on these findings, routine adjuvant HAI after curative resection for colorectal cancer of the liver cannot be recommended. However, given the trend toward a survival benefit at 2 years, further study is recommended.

Antineoplastic Agents↗
PubMed2005

An aggressive surgical approach leads to improved survival in patients with gallbladder cancer: a 12-year study at a North American Center.

OBJECTIVE: To determine if an aggressive surgical approach, with an increase in R0 resections, has resulted in improved survival for patients with gallbladder cancer. SUMMARY BACKGROUND DATA: Many physicians express a relatively nihilistic approach to the treatment of gallbladder cancer; consensus among surgeons regarding the indications for a radical surgical approach has not been reached. METHODS: A retrospective review of all patients with gallbladder cancer admitted during the past 12 years was conducted. Ninety-nine patients were identified. Cases treated during the 12-year period 1990 to 2002 were divided into 2 time-period (TP) cohorts, those treated in the first 6 years (TP1, N = 35) and those treated in the last 6 years (TP2, N = 64). RESULTS: Disease stratification by stage and other demographic features were similar in the 2 time periods. An operation with curative intent was performed on 38 patients. Nine (26%) R0 resections were performed in TP1 and 24 (38%) in TP2. The number of liver resections, as well as the frequency of extrahepatic biliary resections, was greater in TP2 (P < 0.04). In both time periods, an R0 resection was associated with improved survival (P < 0.02 TP1, P < 0.0001 TP2). Overall survival of all patients in TP2 was significantly greater than in TP1 (P < 0.03), with a median survival of 9 months in TP1 and 17 months in TP2. The median 5-year survival in TP1 was 7%, and 35% in TP2. The surgical mortality rate for the entire cohort was 2%, with a 49% morbidity rate. CONCLUSIONS: A margin-negative, R0 resection leads to improved survival in patients with gallbladder cancer.

Adult↗
PubMed2005

Evaluating meta-analyses in the general surgical literature: a critical appraisal.

OBJECTIVE: To assess the methodologic quality of meta-analyses of general surgery topics published in peer-reviewed journals. SUMMARY BACKGROUND DATA: Systematic reviews and meta-analysis are used to seek, summarize, and interpret primary studies on a given topic. Accordingly, systematic reviews and meta-analyses of high-quality primary studies may be the highest level of evidence for issues of prevention and treatment in evidence-based medicine. However, not all published meta-analyses are rigorously performed. METHODS: We searched MEDLINE (from January 1, 1997, to September 1, 2002) and reference lists and solicited general surgery specialists to identify relevant meta-analyses. Inclusion criteria were use of meta-analytic methods to pool the results of primary studies in general surgery on issues of diagnosis, causation, prognosis, or treatment. Our search strategies identified 487 potentially relevant articles. After excluding articles based on a priori criteria, 51 meta-analyses fulfilled eligibility criteria. In duplicate and independently, 2 reviewers assessed the quality of these meta-analyses using a 10-item index called the Overview Quality Assessment Questionnaire. RESULTS: Overall concordance between 2 independent reviewers was good (interobserver agreement 81%, and a kappa of 0.62 (95% CI 0.55-0.69). Of 51 relevant articles, 38 were published in surgical journals. Most studies had major methodologic flaws (median score of 3.3, scale of 1-7). Factors associated with low overall scientific quality included the absence of any prior meta-analyses publications by authors and meta-analyses produced by surgical department members without external collaboration. CONCLUSIONS: This critical appraisal of meta-analyses published in the general surgery literature demonstrates frequent methodologic flaws. The quality of these reports limits the validity of the findings and the inferences that can be made about the primary studies reviewed. To improve the quality of future meta-analyses, we recommend following guidelines for the optimal conduct and reporting of meta-analyses in general surgery.

General Surgery↗
PubMed2005

Well differentiated intrahepatic cholangiocarcinoma in the setting of biliary papillomatosis: a case report and review of the literature.

A 64-year-old man presented with long-standing, vague, epigastric abdominal pain. History, physical examination and laboratory studies were noncontributory. However, serial computed tomography scans revealed a rapidly progressive mass in segment 2 of the liver. Surprisingly, surgical pathology revealed a well-differentiated intrahepatic cholangiocarcinoma associated with biliary papillomatosis (BP). BP is a rare, benign and potentially fatal disease of the intra- and extrahepatic bile ducts. It is typified by numerous multicentric papillary fronds arising from biliary columnar epithelium. Most patients present with symptoms of jaundice and cholangitis. Although a benign disease, a review of the literature demonstrated that BP often recurs after surgical resection, carries a poor prognosis and has a moderately high malignant transformation rate. Treatment options for BP include surgical resection, transplant, ablation, stenting and/or bypass.

Bile Duct Neoplasms↗
PubMed2004

Phase II study of neoadjuvant 5-FU + leucovorin + CPT-11 in patients with resectable liver metastases from colorectal adenocarcinoma.

BACKGROUND: Following resection of liver metastases from colorectal cancer, 5-year survivals are reportedly 30 - 39%. It can be assumed that this clinical situation represents systemic disease. Therefore, it is postulated that systemic chemotherapy would improve outcomes, particularly in those whose disease is sensitive to the agents administered. One potential advantage of neoadjuvant chemotherapy is that it provides in vivo chemosensitivity data. Response to neoadjuvant chemotherapy could therefore guide adjuvant chemotherapy following resection of liver metastases from colorectal cancer. METHODS AND DESIGN: This is a prospective Phase II evaluation of outcomes in patients with potentially resectable liver metastases. Patients will receive neoadjuvant chemotherapy and will undergo resection. Postoperative chemotherapy will be directed by the degree of response to preoperative chemotherapy. All patients with Stage IV colorectal adenocarcinoma isolated to the liver that have disease that is amenable to complete ablation by resection, radiofrequency ablation, and/or cryoablation will be candidates for the trial. Patients will receive CPT-11 180 mg/m2 IV (over 90 minutes) on day 1 with 5-FU 400 mg/m2 bolus and 600 mg/m2 by 22 hour infusion and calcium folinate 200 mg/m2 on days 1 and 2, every 2 weeks. Altogether, six cycles of chemotherapy will be administered. Patients will then undergo resection and/or radiofrequency ablation. Patients who had stable disease or a clinical response with preoperative chemotherapy will receive an additional 12 cycles of CPT-11 180 mg/m2 IV (over 90 minutes) on day 1 with 5-FU 400 mg/m2 bolus and 600 mg/m2 by 22 hour infusion and calcium folinate 200 mg/m2 on days 1 and 2 (given every 2 weeks). Patients with resectable disease who had progressive disease during neoadjuvant chemotherapy will receive best supportive care or an alternative agent, at the discretion of the treating physician. Those patients who are not rendered free of disease following the neoadjuvant chemotherapy and surgery will receive best supportive care or an alternative agent, at the discretion of the treating physician. The primary endpoint of the study is disease-free survival. Secondary endpoints include overall survival, safety and feasibility, response to chemotherapy, and quality of life.

Adenocarcinoma↗
PubMed2004

Multipurpose extended subcostal incision for hepatobiliary surgery.

Exposure is especially important for procedures performed on the liver and biliary tract where careful, precise anatomic dissection of vascular and biliary structures is required. We describe a modified subcostal incision that provides both safe exposure and versatility for most hepatobiliary procedures.

Biliary Tract Surgical Procedures↗
PubMedDate not supplied

Intermittent hepatic vein--total vascular exclusion during liver resection: anatomic and clinical studies.

Bleeding from hepatic veins remains a problem during liver surgery. Perceived difficulties in the dissection and isolation of these retrohepatic venous structures have limited the widespread use of hepatic vein control during liver resection. The purpose of this study was to delineate the anatomy of the hepatic veins and to apply this knowledge to a series of patients undergoing liver resection with intermittent hepatic vein-total vascular exclusion (IHV-TVE). A detailed description of the hepatic venous anatomy was formulated using 20 cadaveric dissections in conjunction with anatomic descriptions during 30 hepatectomies. With the benefit of improved anatomic knowledge, we evaluated a series of 45 consecutive major liver resections in which hepatic veins were isolated and the technique of IHV-TVE was applied. The hepatocaval ligament must be divided to isolate the right hepatic vein. It was closely associated with a caudate vein 69% of the time. The hepatic veins were isolated in 45 consecutive patients who underwent a major hepatic resection. The portal triad and the hepatic veins were occluded intermittently (20 minutes with 5 minutes of reperfusion) with Rommel tourniquets. Mean total warm ischemic time was 65 +/- 24.5 minutes. Mean estimated blood loss was 864 +/- 514 ml. Eighteen percent of patients required blood transfusions. Complications were identified in 16 patients (35.5%), and the average length of hospital stay was 10.5 +/- 3.4 days. There were no deaths. Detailed anatomic knowledge of the hepatocaval ligament and the hepatic veins allows for safe extrahepatic control of the hepatic veins during major hepatic surgery. The technique was well tolerated and may have limited intraoperative blood loss.

Aged↗