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Elijah Dixon

Publications and source records attributed to Elijah Dixon.

At least 19 recordsLinked to original sources

Chemotherapy for colorectal cancer prior to liver resection for colorectal cancer hepatic metastases does not adversely affect peri-operative outcomes.

BACKGROUND: Systemic chemotherapy is being used increasingly in patients with colorectal cancer. The effects of prior systemic adjuvant or palliative chemotherapy on morbidity following hepatic resection for metastases are not well defined. OBJECTIVES: To assess the peri-operative impact of systemic chemotherapy on liver resection for colorectal cancer hepatic metastases. METHODS: Ninety-six resections for colorectal cancer hepatic metastases performed from July 2001 to July 2003 (93% > or =2 segments) were reviewed. Pre-operative demographics, peri-operative features, and post-operative outcomes were collected prospectively. Type of chemotherapy and the temporal relationship of chemotherapy to the liver resection were analyzed. RESULTS: Fifty-three of 96 patients (55%) received a mean of 5.7 cycles (6.1 months) of systemic chemotherapy prior to hepatic resection, with a median interval of 12 months from end of chemotherapy to liver resection (range 1-75 months). Thirty-five received 5-fluorouracil/leucovorin (5-FU/LV) alone, nine had irinotecan (CPT-11) in addition to 5-FU/LV, and nine were not specified. Pre-operative age, sex, co-morbidities, ASA score, biochemical and liver enzyme profiles, tumor number, and extent and technique of hepatic resection were the same in the chemotherapy and non-chemotherapy cohorts. Mean tumor size was smaller (4.5 cm vs. 5.8 cm) and synchronous metastases were half as common (25% vs. 49%) in the chemotherapy group. Liver resection operative time was equivalent (270 min) in the two groups. Higher estimated blood loss (EBL) (1,000 ml vs. 850 ml), but fewer transfusions (23% vs. 15%) were associated with the chemotherapy group. Although not statistically significant, post-operative liver enzyme peaks were higher in the chemotherapy group (AST = 402 U/L vs. 302 U/L, P = 0.09 and ALT = 433 U/L vs. 312 U/L, P = 0.1). Peak changes in INR and serum bilirubin did not differ. Complications and length of stay (LOS) did not differ between the groups. The only post-operative death was in the non-chemotherapy group. Interestingly, hepatic steatosis was present in 28% of the non-chemotherapy cases and 57% of the chemotherapy resection specimens (P = 0.005) and was marked (>30%) in 7% and 10%, respectively. Further analysis of the chemotherapy group based on the interval between completion of chemotherapy and the hepatic resection (<6 months, 7-12 months, 1-2 years, and >2 years) revealed a trend towards worse outcomes in most categories for those in the >2 years cohort. When comparing the 5-FU/LV alone, to the CPT-11 group there were no significant differences except higher intra-operative blood loss in the group receiving 5-FU/LV alone (1,295 ml vs. 756 ml, P = 0.01). CONCLUSION: Despite variations in biochemical function and hepatic steatosis, short-term clinical outcomes are not affected by the administration of chemotherapy prior to hepatic resection. Furthermore, there is no detrimental effect of close timing of chemotherapy prior to resection, and there are no appreciable differences between irinotecan containing regimes and more traditional 5-FU-only based therapies, although the subset sample sizes were small in this study.

Antineoplastic Combined Chemotherapy Protocols↗

Functioning and nonfunctioning neuroendocrine tumors of the pancreas.

PURPOSE OF REVIEW: Neuroendocrine tumors of the pancreas are a small subgroup of tumors characterized by a variety of biological behaviors. Recent changes in their classification should help better define the prognosis of this diverse group of tumors. With recent advances in diagnosis and staging, the treatment options for all neuroendocrine tumors have evolved. Presented here is a review of the current-day knowledge for neuroendocrine tumors of the pancreas. RECENT FINDINGS: A consensus by leading experts in the neuroendocrine tumors field has proposed an algorithm for the diagnosis, treatment and follow-up of these rare tumors. Surgical resection remains the first-line therapy. Alternative forms of cytoreduction such as radiofrequency ablation and embolization, have increased the ability of the surgeon to debulk these tumors, resulting in improved survival and better palliation. Contrary to adenocarcinoma of the pancreas, hormonal and biotherapy offer unique treatment strategies for these rare tumors. Very recent developments utilizing radionuclide therapy hold promise for not only palliation, but may prove to be a beneficial form of adjuvant therapy. SUMMARY: Presented here is a summary of the recent literature on the diagnosis and treatment of neuroendocrine tumors of the pancreas.

Humans↗

Impact of regional lymph node evaluation in staging patients with periampullary tumors.

BACKGROUND: Two distinct lymph nodes reproducibly assessed by computed tomography for the evaluation of periampullary tumors are the common bile duct (CBD) node and the gastroduodenal artery (GDA) node. We examined whether radiographical enlargement of either lymph node predicts tumor resectability, nodal metastasis, or patient survival. METHODS: Ninety-four consecutive patients underwent attempted curative resection of periampullary tumors between September 2001 and June 2003. A single radiologist recorded in a retrospective, blinded fashion the short- and long-axis measurements of the CBD and GDA nodes. RESULTS: Sixty-one percent (n = 57) of tumors were resectable by pancreaticoduodenectomy. Overall, actual 6-, 12-, and 18-month survival was 87%, 68%, and 63%, respectively. Enlarged radiographical nodal size by either axis was not associated with the presence of metastasis to these lymph nodes or with reduced overall patient survival. Only a CBD node short-axis size >10 mm predicted unresectability (odds ratio, 3.2; P = .036). Liver metastasis and/or carcinomatosis were present in 43% of unresectable patients, and this was associated with decreased survival at both 1 year (25% vs. 77%; P < .001) and 18 months (19% vs. 72%; P <.001). A pathologic diagnosis of metastasis to the GDA node, but not the CBD node, was associated with a similarly decreased survival (1 year: 33% vs. 78%, P = .028; 18 months: 22% vs. 70%, P = .023). CONCLUSIONS: For presumed periampullary malignancy, a CBD node short-axis size >10 mm predicts tumor unresectability. Metastatic disease to the GDA node, particularly for pancreatic adenocarcinoma, portends a poor prognosis equivalent to that of hepatic or peritoneal spread. Given these findings, radiographical CBD lymph node measurements may guide selection for performing laparoscopic staging with or without ultrasonography in conjunction with GDA nodal biopsy in patients with periampullary malignancy.

Abdomen↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗