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Dive into the research topics where Douglas L. Fraker is active.

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Featured researches published by Douglas L. Fraker.


The New England Journal of Medicine | 1999

Surgery to cure the Zollinger-Ellison syndrome.

Jeffrey A. Norton; Douglas L. Fraker; H R Alexander; David Venzon; J L Doppman; Serrano J; Goebel Su; Peghini Pl; Roy Pk; Fathia Gibril; Robert T. Jensen

BACKGROUND AND METHODS The role of surgery in patients with the Zollinger-Ellison syndrome is controversial. To determine the efficacy of surgery in patients with this syndrome, we followed 151 consecutive patients who underwent laparotomy between 1981 and 1998. Of these patients, 123 had sporadic gastrinomas and 28 had multiple endocrine neoplasia type 1 with an imaged tumor of at least 3 cm in diameter. Tumor-localization studies and functional localization studies were performed routinely. All patients underwent surgery according to a similar operative protocol, and all patients who had surgery after 1986 underwent duodenotomy. RESULTS The 151 patients underwent 180 exploratory operations. The mean (+/-SD) follow-up after the first operation was 8+/-4 years. Gastrinomas were found in 141 of the patients (93 percent), including all of the last 81 patients to undergo surgery. The tumors were located in the duodenum in 74 patients (49 percent) and in the pancreas in 36 patients (24 percent); however, primary tumors were found in lymph nodes in 17 patients (11 percent) and in another location in 13 patients (9 percent). The primary location was unknown in 24 patients (16 percent). Among the patients with sporadic gastrinomas, 34 percent were free of disease at 10 years, as compared with none of the patients with multiple endocrine neoplasia type 1. The overall 10-year survival rate was 94 percent. CONCLUSIONS All patients with the Zollinger-Ellison syndrome who do not have multiple endocrine neoplasia type 1 or metastatic disease should be offered surgical exploration for possible cure.


Gastroenterology | 1995

Determinants of metastatic rate and survival in patients with zollinger-ellison syndrome: A prospective long-term study

H. Christian Weber; David Venzon; Jaw-Town Lin; Vitaly A. Fishbein; Murray Orbuch; Doris B. Strader; Fathia Gibril; David C. Metz; Douglas L. Fraker; Jeffrey A. Norton; Robert T. Jensen

BACKGROUND/AIMS It is unclear whether tumor location, size, or the presence of multiple endocrine neoplasia type 1 (MEN-1) alters metastatic rate and survival in patients with pancreatic endocrine tumors. The purpose of this study was to determine the prognostic factors of survival and metastatic rate in patients with Zollinger-Ellison syndrome (ZES). METHODS Data were analyzed from 185 consecutive patients with ZES who were followed up prospectively. RESULTS Liver metastases were present in 24% of patients and correlated with the size of the primary tumor. Duodenal tumors were smaller than pancreatic tumors. Liver metastases occurred more often (P < 0.00001) with pancreatic than duodenal tumors, whereas the metastatic rate to lymph nodes was not different. Survival of patients with liver but not lymph node metastases was shortened. In patients with sporadic ZES, liver metastases were more common during the initial evaluation and survival was decreased compared with patients with MEN-1; however, during follow-up, an equal percentage of patients with and without MEN-1 developed liver metastases. CONCLUSIONS Survival was primarily determined by the presence of liver metastases. The frequency of liver metastases depends on the size and location of the primary tumor and on the presence of MEN-1 at the initial presentation. Metastases to the lymph nodes do not depend on these factors. A benign and malignant form of ZES exists.


Annals of Surgery | 1996

A prospective trial evaluating a standard approach to reoperation for missed parathyroid adenoma.

Nora Jaskowiak; Jeffrey A. Norton; H. Richard Alexander; John L. Doppman; Thomas H. Shawker; Monica C. Skarulis; Stephen J. Marx; Allen M. Spiegel; Douglas L. Fraker

OBJECTIVES The authors evaluate the results of preoperative imaging protocols and surgical re-exploration in a series of patients with missed parathyroid adenomas after failed procedures for primary hyperparathyroidism. BACKGROUND The success rate is lower and the complication rate is increased in patients undergoing reoperation for primary hyperparathyroidism compared with initial procedures. Scarring and distortion of tissue planes plus the potential for ectopic gland location leads to this worsened outcome. METHODS Two hundred eighty-eight consecutive patients with persistent/recurrent hyperparathyroidism were treated at a single institution after a failed procedure or procedures at outside institutions. Two hundred twenty-two of these patients (77%) were believed to have a missed single adenoma, and these patients underwent 228 operations and 227 preoperative work-ups. Preoperative evaluation consisted of a combination of four noninvasive imaging studies--neck ultrasound, nuclear medicine scan, neck and mediastinal computed tomography scan, and neck and mediastinal magnetic resonance imaging. Based on the noninvasive testing alone, 27% patients underwent surgery whereas the other patients underwent invasive studies, including selective angiography (58%), selective venous sampling for parathyroid hormone (43%), or percutaneous aspiration of suspicious lesions (15%). RESULTS Abnormal parathyroid adenomas were found in 209 of 222 initial procedures and 6 of 6 second procedures, with an overall success rate in terms of resolution of hypercalcemia in 97% (215/222) of patients. The single most common site of missed adenoma glands was in the tracheal-esophageal groove in the posterior superior mediastinum (27%). The most common ectopic sites for parathyroid adenomas are thymus (17%), intrathyroidal (10%), undescended glands (8.6%), carotid sheath (3.6%), and the retroesophageal space (3.2%). The most sensitive and specific noninvasive imaging test is the sestamibi subtraction scan, with 67% true-positive and no false-positive results. The rate of true-positive and false-positive results for ultrasound, computed tomography, magnetic resonance imaging, and technetium thallium scans were 48%/21%, 52%/16%, 48%/14% and 42%/8%, respectively. The incidence of injury to the recurrent laryngeal nerve was 1.3%. CONCLUSIONS A single missed parathyroid adenoma is the most common cause for a failed initial parathyroid operation. Appropriate use of preoperative imaging tests and knowledge of the potential location or parathyroid adenomas can lead to very high cure rates with minimal morbidity.


Journal of Clinical Oncology | 1998

Isolated hepatic perfusion with tumor necrosis factor and melphalan for unresectable cancers confined to the liver.

H R Alexander; David L. Bartlett; Steven K. Libutti; Douglas L. Fraker; T Moser; Steven A. Rosenberg

PURPOSE To evaluate the efficacy and systemic and regional toxicities of hyperthermic isolated hepatic perfusion (IHP) using tumor necrosis factor (TNF) and melphalan for the treatment of unresectable primary or metastatic cancers confined to the liver. PATIENTS AND METHODS Thirty-four patients (18 men and 16 women; mean age, 49 years) underwent a 60-minute hyperthermic (39.5 degrees to 40.0 degrees C) IHP performed by laparotomy that used TNF 1.0 mg and melphalan 1.5 mg/kg. Perfusion inflow was through the gastroduodenal artery and outflow was from a cannula positioned in an isolated segment of retrohepatic inferior vena cava (IVC). Infrahepatic IVC and portal venous blood flow were shunted to the axillary vein using an external venoveno bypass circuit. Complete vascular isolation of the liver was confirmed by an I-131-labelled human serum albumin monitoring technique. RESULTS There was no operative mortality. Seventy-five percent of patients had reversible grade III or IV (National Cancer Institute Common Toxicity Criteria) hepatic toxicity with one treatment-related mortality (3%) because of hepatic venoocclusive disease. In 33 assessable patients, the overall response rate was 75% (complete response, one patient [3%]; partial response, 26 patients [72%]). With a median potential follow-up of 15 months, the mean duration of response was 9 months (range, 2 to 30 months). CONCLUSION IHP with TNF and melphalan results in significant regression of bulky hepatic cancers confined to the liver in the majority of patients. Based on these initial results, further refinement of this treatment technique is warranted; perhaps by the combination of IHP with other regional treatment strategies to provide long-term control of unresectable cancers confined to liver.


Annals of Surgery | 1994

Surgery in Zollinger-Ellison syndrome alters the natural history of gastrinoma

Douglas L. Fraker; Jeffrey A. Norton; H R Alexander; David Venzon; Robert T. Jensen

ObjectiveThe authors assessed the impact of gastrinoma resection on the subsequent development of hepatic metastases in Zollinger-Ellison syndrome. Summary Background DataThe symptoms of acid hypersecretion can be controlled medically in Zollinger-Ellison syndrome with high-dose pharmacologic therapy. The current role of surgery is curative excision of the gastrinoma. Because biochemical cure is obtained only in a portion of the patients and the neoplastic disease may be indolent in this syndrome, the ability of surgical resection of gastrinoma to alter or improve the subsequent development of hepatic metastases and mortality has not been defined. MethodsOne hundred twenty-four patients with the biochemical diagnosis of Zollinger-Ellison syndrome and no hepatic metastases on initial imaging studies were evaluated. Ninety-eight patients underwent surgical exploration for curative gastrinoma resections while 26 patients were managed medically. Long-term follow-up regarding development of hepatic metastases and survival were evaluated. ResultsSurgical exploration with gastrinoma excision resulted in a significantly decreased incidence of hepatic metastases 3% (3/98) compared with patients managed medically 23% (6/26) with comparable follow-up (p < 0.003). Two deaths due to metastatic gastrinoma occurred in the nonoperative group compared with no disease-specific deaths in the surgical group (p = 0.085). ConclusionsFor the patient with Zollinger-Ellison syndrome without metastatic disease, surgical exploration with attempted curative gastrinoma resection is recommended because it may alter the natural history of this syndrome.


Annals of Surgery | 1990

Localization and surgical treatment of occult insulinomas.

Jeffrey A. Norton; Thomas H. Shawker; John L. Doppman; Donald L. Miller; Douglas L. Fraker; Douglas T. Cromack; Phillip Gorden; Robert T. Jensen

Management of patients with biochemical evidence of insulinoma and negative preoperative imaging studies (occult) tumors is controversial, varying from primarily medical management to aggressive, blind nearly total pancreatectomy to extirpate the tumor. Since 1982, 12 consecutive patients with occult insulinoma underwent preoperative portal venous sampling (PVS) for insulin followed by surgical exploration with intraoperative ultrasound (IOUS). Eleven of twelve patients (92%) had insulinoma removed and were cured. Portal venous sampling correctly predicted the location of the insulinoma in 9 patients (75%) and that no tumor would be found in another patient. A fourfold insulin gradient in the pancreatic tail of one patient correctly predicted that a distal pancreatectomy would remove the insulinoma despite the fact that neither palpation nor IOUS identified any tumor. Intraoperative ultrasound was the single best method to identify occult tumors because it correctly identified 10 of 11 insulinomas that were found, including five pancreatic head tumors that were not palpable. Palpation identified five insulinomas. Of the 10 tumors that were identified during operation by palpation or ultrasound, IOUS identified significantly more (100% versus 50%, p = 0.03) and guided the successful enucleation of each. The results support the strategy of preoperative PVS and operation with IOUS to localize and remove insulinoma in patients with occult tumors. Most tumors (75%) will be correctly localized to a specific pancreatic region by preoperative PVS and identified by IOUS (83%), allowing simple enucleation and biochemical correction of hypoglycemia. Morbid blind pancreatic resections are no longer indicated and long-term medical management of hypoglycemia should be reserved for the occasional patient (8%) who fails preoperative PVS and operation guided by IOUS.


Journal of Clinical Investigation | 1991

Treatment with recombinant human tumor necrosis factor-alpha protects rats against the lethality, hypotension, and hypothermia of gram-negative sepsis.

H R Alexander; Brett C. Sheppard; Jensen Jc; Howard N. Langstein; C M Buresh; David Venzon; E Walker; Douglas L. Fraker; Mark C. Stovroff; Jeffrey A. Norton

Tumor necrosis factor (TNF) is a peptide secreted by macrophages in response to endotoxin that can produce many of the changes seen in septic shock. After cecal ligation and puncture (CLP) rats gradually develop tachycardia, hypotension, tachypnea, and hypothermia. At 5 h post-CLP, rats have a peak in serum levels of endotoxin and 60% of rats have blood cultures that grow Gram-negative rods (Escherichia coli and Klebsiella pneumonia). At 20 h post-CLP all rats develop positive blood cultures. Serum levels of TNF are not reproducibly measurable in rats following CLP. Rats undergoing CLP have a 50-80% mortality with deaths usually occurring 24-72 h postinjury. Repetitive (twice daily x 6 d) i.p. injection of sublethal doses of recombinant human TNF-alpha (100 micrograms/kg) to rats undergoing CLP 1 d after the treatment period resulted in a significant reduction in mortality compared to control rats previously unexposed to rTNF (P less than 0.03). Animals treated with rTNF had no hypotension or hypothermia after CLP and regained normal food intake faster than control rats. 12 h after CLP the gene expression for manganous superoxide dismutase (MnSOD), an inducible mitochondrial metalloenzyme responsible for cellular resistance to injury from toxic reactive oxygen species, was higher in livers of rats treated with rTNF suggesting that the TNF treatment augmented expression of this protective enzyme. Unlike MnSOD, expression of the gene for copper-zinc SOD was not affected by CLP or rTNF treatment. The results suggest that prior treatment with recombinant TNF can ameliorate the lethality, hypotension, hypothermia, and anorexia of Gram-negative sepsis in rats and that the mechanism may be related to enhanced hepatic expression of the gene for MnSOD. Repeated administration of recombinant TNF may be a strategy to minimize mortality and morbidity of Gram-negative sepsis.


Surgery | 1995

Prospective study of surgical resection of duodenal and pancreatic gastrinomas in multiple endocrine neoplasia type 1

Mark P. Macfarlane; Douglas L. Fraker; H. Richard Alexander; Jeffrey A. Norton; Irina A. Lubensky; Robert T. Jensen

BACKGROUND The role of surgical resection of gastrinoma in multiple endocrine neoplasia type 1 (MEN 1) is controversial because of low biochemical cure rates, but with adequate duodenal exploration higher cure rates may be possible. METHODS We have prospectively evaluated this proposal in ten consecutive patients with MEN 1 and Zollinger-Ellison syndrome who underwent surgical exploration for gastrinoma resection including a detailed evaluation of the duodenum by palpation, intraoperative endoscopy with transillumination, and duodenotomy. RESULTS Duodenal tumors were present in seven patients. Six of seven patients had metastatic deposits in lymph nodes, and two of seven had synchronous pancreatic tumors. Three patients had a single duodenal tumor, one patient had two tumors, and three patients had more than 20 duodenal tumors. Positive gastrin staining by use of immunohistochemistry was seen in all duodenal tumors. None of these seven patients were biochemically cured. Of three patients with negative duodenal explorations, two had single pancreatic tumors removed and one had only lymph node gastrinoma. No patients were biochemically cured. CONCLUSIONS Not all patients with MEN 1 and Zollinger-Ellison syndrome have duodenal gastrinomas. In the 70% of patients with duodenal tumors, even extensive duodenal exploration with removal of positive lymph nodes does not result in cures because 86% of tumors had metastasized to lymph nodes and 43% of patients had large numbers of tumors.


Journal of Clinical Oncology | 1995

Cytokine levels and systemic toxicity in patients undergoing isolated limb perfusion with high-dose tumor necrosis factor, interferon gamma, and melphalan.

A K Thom; Alexander Hr; M P Andrich; W C Barker; Steven A. Rosenberg; Douglas L. Fraker

PURPOSE Isolated limb perfusion (ILP) with tumor necrosis factor (TNF), interferon gamma, and melphalan (M) has been reported to result in high response rates for extremity melanoma and sarcoma. We have evaluated the relationship of systemic TNF exposure to induction of several secondary mediators and incidence of systemic toxicity. PATIENTS AND METHODS Nineteen patients with extremity melanoma (n = 16) or sarcoma (n = 3), underwent 90-minute ILP with TNF-alpha, interferon gamma (0.2 mg), and M (10 to 13 mg/L of limb volume) (TNF/IFN/M) (n = 12), or M alone (n = 7). Continuous intraoperative monitoring (CIM) for systemic leak from the perfusion circuit was performed using radioactive iodine-131 albumin. Cytokine levels in the perfusate and systemic circulation during and after ILP were measured by enzyme-linked immunosorbent assay. RESULTS Systemic leaks > or = 1% from the perfusion circuit occurred in six patients who received TNF/IFN/M and in four who received M alone. Hypotension that required vasopressor support occurred in six of six patients with evidence of a leak (> or = 1%) and zero of six patients without a leak (< 1%). These six patients had significantly higher peak systemic TNF levels during and after perfusion than patients without a leak (2.8 and 8.2 ng/mL v 0.7 and 2.0 ng/mL, respectively; P < .05). All patients who received TNF/IFN/M had significantly greater increases in systemic interleukin-6 (IL-6) levels than in patients with M alone (12,395 +/- 10,374 pg/mL v 79.4 +/- 7.2 pg/mL, respectively; P < .001). Intracellular adhesion molecule (ICAM), IL-8, and TNF-R levels were also increased after ILP with TNF/IFN/M. CONCLUSION ILP with TNF/IFN/M can be safely performed, as I131 albumin provides a sensitive measure of systemic leakage from the perfusion circuit. Patients with a measured leak of > or = 1% develop mild and transient postoperative hypotension with significantly higher systemic TNF levels and lower perfusate TNF levels than in patients without leaks.


Cytokine | 1994

Characterization of differentiation factor/leukaemia inhibitory factor effect of lipoprotein lipase activity and mRNA in 3T3-L1 adipocytes

Maria Berg; Douglas L. Fraker; H. Richard Alexander

Alterations in lipid metabolism characterized in major part by a decrease in lipoprotein lipase (LPL) activity in adipose tissue are a central feature of cachexia from chronic infection or malignancy. These metabolic derangements may be mediated in large part through endogenous host proteins produced in response to various pathological stimuli. Differentiation factor/leukaemia inhibitory factor (D-factor) is a cytokine whose functions overlap those of tumour necrosis factor-alpha (TNF), IL-6 and IL-1. Recombinant murine D-factor produced a dose- and time-dependent inhibition of heparin-releasable LPL activity in differentiated 3T3-L1 adipocytes. Although 2-10 fold less potent than recombinant murine TNF, D-factor inhibited LPL activity at concentrations of 1-10 ng/ml. When added together, D-factor and TNF produced a synergistic inhibition of LPL activity. Interleukin 6 (IL-6) was 100-fold less potent than D-factor; 0.1 ng/ml of D-factor or 10 ng/ml of IL-6 caused a 50% inhibition of LPL activity. D-factor and TNF increased IL-6 production in 3T3-L1 cells. Ten ng/ml of D-factor or 1.0 ng/ml of TNF stimulated the release of < 1 ng/ml of IL-6 and inhibited LPL activity to 11 +/- 3% and 3 +/- 2% of control, respectively, whereas 50 ng/ml of recombinant IL-6 was required to decrease LPL activity to 24 +/- 19% of control. TNF produced a marked decrease in LPL mRNA, whereas D-factor had minimal or no effect at doses which inhibited LPL activity almost completely. Western blot analysis of cell extracts showed that TNF caused a greater decrease in LPL protein production than D-factor.2+ with TNF, may contribute to the manifestations of cachexia.

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John L. Doppman

National Institutes of Health

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H R Alexander

National Institutes of Health

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Monica C. Skarulis

National Institutes of Health

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Robert T. Jensen

National Institutes of Health

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Allen M. Spiegel

National Institutes of Health

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Stephen J. Marx

National Institutes of Health

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David Venzon

National Institutes of Health

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David L. Bartlett

National Institutes of Health

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