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P Pederzoli

Publications and source records attributed to P Pederzoli.

At least 37 records · Page 2Linked to original sources

Infection prevention in necrotizing pancreatitis: an old challenge with new perspectives.

Necrotizing pancreatitis still remains a life-threatening disease despite several improvements in diagnosis, prevention and treatment. In recent years, some important questions have been answered such as the need for early intensive medical treatment rather than early surgery, but others are still strongly debated. The aim of this paper is to present an up-to-date assessment of current challenges in the management of necrotizing pancreatitis in order to prevent infection.

Antibiotic Prophylaxis↗

Surgical strategy in the treatment of gastrointestinal neuroendocrine tumours.

The aim of this study was to analyze the indications and type of surgery to be performed in patients suffering from the more common gastrointestinal neuroendocrine tumours. The different patterns of tumour spread are considered (local, locoregional and metastatic disease) along with the indications according to three main objectives, namely, identification of the disease, cure and care. The surgical procedures of choice in relation to the different tumour subtypes are also analyzed, and the main controversies relating to cytoreductive surgery are discussed.

Gastrointestinal Neoplasms↗

Influence of resection margins on survival for patients with pancreatic cancer treated by adjuvant chemoradiation and/or chemotherapy in the ESPAC-1 randomized controlled trial.

OBJECTIVE: To assess the influence of resection margins on survival for patients with resected pancreatic cancer treated within the context of the adjuvant European Study Group for Pancreatic Cancer-1 (ESPAC-1) study. SUMMARY BACKGROUND DATA: Pancreatic cancer is associated with a poor long-term survival rate of only 10% to 15% after resection. Patients with positive microscopic resection margins (R1) have a worse survival, but it is not known how they fare in adjuvant studies. METHODS: ESPAC-1, the largest randomized adjuvant study of resectable pancreatic cancer ever performed, set out to look at the roles of chemoradiation and chemotherapy. Randomization was stratified prospectively by resection margin status. RESULTS: Of 541 patients with a median follow-up of 10 months, 101 (19%) had R1 resections. Resection margin status was confirmed as an influential prognostic factor, with a median survival of 10.9 months for R1 versus 16.9 months months for patients with R0 margins. Resection margin status remained an independent factor in a Cox proportional hazards model only in the absence of tumor grade and nodal status. There was a survival benefit for chemotherapy but not chemoradiation, irrespective of R0/R1 status. The median survival was 19.7 months with chemotherapy versus 14.0 months without. For patients with R0 margins, chemotherapy produced longer survival compared with to no chemotherapy. This difference was less apparent for the smaller subgroup of R1 patients, but there was no significant heterogeneity between the R0 and R1 groups. CONCLUSIONS: Resection margin-positive pancreatic tumors represent a biologically more aggressive cancer; these patients benefit from resection and adjuvant chemotherapy but not chemoradiation. The magnitude of benefit for chemotherapy treatment is reduced for patients with R1 margins versus those with R0 margins. Patients with R1 tumors should be included in future trials of adjuvant treatments and randomization and analysis should be stratified by this significant prognostic factor.

Adenocarcinoma↗

Previous cholecystectomy, gastrectomy, and diabetes mellitus are not crucial risk factors for pancreatic cancer in patients with chronic pancreatitis.

INTRODUCTION: In the general population, cholecystectomy, diabetes, and chronic pancreatitis seem to be associated with an increased risk of developing pancreatic cancer. AIMS: We assessed whether previous cholecystectomy, gastrectomy, or diabetes mellitus may be risk factors for pancreatic cancer in patients with chronic pancreatitis. METHODOLOGY: We analyzed 853 patients with chronic pancreatitis (110 women, 743 men) with a median follow-up period of 14 years with particular reference to establishing which patients had previously undergone cholecystectomy or distal gastric resection (Billroth II anastomosis) or had diabetes or gallstone disease and the respective time scales involved. RESULTS: Pancreatic cancer developed in 17 patients with chronic pancreatitis after a median period of 8 years from onset of pancreatitis symptoms (range, 3-38 years). Excluding two cholecystectomies performed 1 year before diagnosis of cancer, cholecystectomy was performed in 7/17 (41%) patients with pancreatic cancer and in 381/836 (46%) of the other patients with chronic pancreatitis. Forty-nine (10%) patients with chronic pancreatitis and no pancreatic cancer had undergone cholecystectomy during the years before the onset of chronic pancreatitis, whereas none of the patients in whom a pancreatic malignancy developed had undergone cholecystectomy before the onset of chronic pancreatitis symptoms. Gastrectomies were performed in 116 patients (14%), 47 before the onset of chronic pancreatitis. Only 2/17 patients with pancreatic cancer had undergone previous gastrectomy, though in both cases only shortly before diagnosis of the cancer. Diabetes was diagnosed in 353 patients, but only in 30 (4%) before onset of chronic pancreatitis. Only 1/17 patients (6%) with pancreatic cancer had long-standing diabetes, whereas diabetes developed in 3/17 shortly before diagnosis of pancreatic cancer. CONCLUSIONS: Cholecystectomy, gastrectomy, and diabetes are not major risk factors for the development of pancreatic cancer in patients with chronic pancreatitis.

Cholecystectomy↗

The relevance of gastrointestinal fistulae in clinical practice: a review.

Gastrointestinal fistulae most frequently occur as complications after abdominal surgery (75-85%) although they can also occur spontaneously--for example, in patients with inflammatory bowel disease (IBD) such as diverticulitis or following radiation therapy. Abdominal trauma can also lead to fistula formation although this is rare. Postoperative gastrointestinal fistulae can occur after any abdominal procedure in which the gastrointestinal tract is manipulated. Regardless of the cause, leakage of intestinal juices initiates a cascade of events: localised infection, abscess formation and, as a result of a septic focus, fistulae formation. The nature of the underlying disease may also be important, with some studies showing that fistula formation is more frequent following surgery for cancer than for benign disease. Fistula formation can result in a number of serious or debilitating complications, ranging from disturbance of fluid and electrolyte balance to sepsis and even death. The patient will almost always suffer from severe discomfort and pain. They may also have psychological problems, including anxiety over the course of their disease, and a poor body image due to the malodorous drainage fluid. Postoperative fistula formation often results in prolonged hospitalisation, patient disability, and enormous cost. Therapy has improved over time with the introduction of parental nutrition, intensive postoperative care, and advanced surgical techniques, which has reduced mortality rates. However, the number of patients suffering from gastrointestinal fistulae has not declined substantially. This can partially be explained by the fact that with improved care, more complex surgery is being performed on patients with more advanced or complicated disease who are generally at higher risk. Therefore, gastrointestinal fistulae remain an important complication following gastrointestinal surgery.

Humans↗

Management of complications after pancreaticoduodenectomy in a high volume centre: results on 150 consecutive patients.

Pancreaticoduodenectomy (PD) is still a difficult procedure with significant morbidity. We report 150 consecutive PDs performed during a 3-year period. All the cases have been prospectively evaluated with regard to the surgical outcome. Mortality in this series was 3/150 (2%) with a re-operation rate of 5/150 (3.3%); surgical complications were experienced in 57/150 (38%). The most frequent complications were collections in 25/150 (16.6%) and pancreatic fistulas in 16/150 (10.7%). The majority of these complications were conservatively managed: only one abscess and one fistula due to an anastomotic dehiscence required re-operation. The complication most responsible for mortality was haemorrhage secondary to arterial pseudoaneurysms in patients with severe post-operative pancreatitis. The continued high morbidity of PDs is compensated by the ability to treat complications non-operatively, resulting in a surgical risk that should now be considered medium to low in high volume centres.

Acute Disease↗

In vivo octreotide administration acutely reduces exocrine granule size in the human pancreas.

BACKGROUND: Octreotide has been found to be effective in the prevention of postoperative complications of pancreatic surgery, but the benefit of preoperative octreotide administration has not been assessed. AIMS: To evaluate the ability of octreotide in reducing the amount of digestive enzymes in the pancreas before surgery, a morphometric ultrastructural study of the gland was undertaken in patients undergoing demolitive pancreatic surgery. METHODS: Twenty-three inpatients received saline (n = 8) or octreotide (100 micrograms s.c.) before surgery either once (n = 5), or three (n = 5) or six (n = 5) times at 8-hour intervals. At surgery, biopsies of the pancreas were taken and processed for electron microscopy. Several parameters were assessed in exocrine cells by means of ultrastructural morphometry. RESULTS: A single administration of octreotide significantly reduced the exocrine granule number and the mean and total granular surface sectional area, and the ratio between granule area and cytoplasmic area. Repeated octreotide administrations were associated with partial (3 administrations) and complete (6 administrations) recovery of all parameters to control values. CONCLUSION: Preoperative administration of octreotide, the synthetic analogue of somatostatin, acutely reduces exocrine granule number and size in the pancreatic cell. This finding can partially explain the prophylactic effect of the drug on early complications of pancreatic surgery. Such an effect is not maintained over multiple administrations of the somatostatin analogue. Possible explanations for this latter finding are discussed.

Adult↗

Collagen type I synthesized by pancreatic periacinar stellate cells (PSC) co-localizes with lipid peroxidation-derived aldehydes in chronic alcoholic pancreatitis.

Chronic alcoholic pancreatitis (CAP) is characterized by progressive pancreatic fibrosis and loss of the acinar cell mass, but the pathogenesis of pancreatic fibrosis in the human is poorly understood. It has been recently suggested that lipid peroxidation-derived aldehydes such as 4-hydroxynonenal (HNE) are involved in tissue damage and fibrosis in other organs. The aim of this study was to evaluate the role of oxidative stress in the development of alcohol-induced pancreatic fibrosis in humans, and to assess the contribution of pancreatic periacinar stellate cells (PSC) in the in vivo synthesis of extracellular matrix components during CAP. Lipid peroxidation was evaluated in tissue specimens obtained from patients with CAP who underwent surgical procedures, by immunohistochemistry using a monoclonal antibody directed against HNE-protein adducts. Immunohistochemical determination of collagen type I, alpha-smooth muscle actin (alpha-SMA), and the beta subunit of human platelet-derived growth factor (PDGF-Rbeta) was also performed. In addition, the tissue mRNA expression of procollagen I, PDGF-Rbeta, and transforming growth factor-beta1 (TGF-beta1) was evaluated by in situ hybridization. In CAP, increased formation of HNE-protein adducts was evident in acinar cells adjacent to the interlobular connective tissue that stained positively for collagen type I. HNE staining was absent in normal pancreas. Several non-parenchymal periacinar cells (PSC) underlay the HNE-stained acinar cells. Those PSC stained positively for alpha-SMA and PDGF-Rbeta and showed active synthesis of procollagen type I by in situ expression of the specific mRNAs. The pattern of expression of PDGF-Rbeta mRNA reflected that observed in immunostaining, showing increased amounts of transcripts in PSC. TGF-beta1 mRNA expression was increased in CAP, but transcripts were found in several cell types including PSC, acinar, and ductal cells. These results indicate that significant lipid peroxidation phenomena occur in CAP and that they are associated with active synthesis of collagen by PSC.

Actins↗

Role of octreotide in the treatment of external pancreatic pure fistulas: a single-institution prospective experience.

INTRODUCTION: Octreotide was studied in the treatment of pure external pancreatic fistulas. METHODS: Eighteen cases (12 males, 6 females) were prospectively observed. Six patients (four after radical surgery for periampullary cancer, one endocrine tumor enucleation and one pancreojejunostomy in chronic pancreatitis) were treated as outpatients with octreotide alone because of low basal fistula output (mean+/-SD: 96.6+/-27.4 cc/24 h). Twelve (five radical surgery for cancer, five surgery for severe pancreatitis, one enucleation and one pancreojejunostomy) were treated as inpatients with octreotide plus total parenteral nutrition because of the high output (mean+/-SD: 448.4+/-248.2 cc/24 h). RESULTS: Ten of the 12 high-output fistulas healed in 27.8+/-27.7 days, whereas all low-output fistulas healed in 12.1+/-6.6 days. CONCLUSION: Octreotide appears useful in the treatment of external pancreatic fistulas. For optimal results to be achieved, there must be no local infection and no mechanical or anatomical obstacles to the free flow of juice.

Adolescent↗

A single-institution experience with fistulojejunostomy for external pancreatic fistulas.

External pancreatic fistulas resistant to medical treatment are an indication for surgery. Over the period from May 1986 to March 1999, we operated on 17 patients suffering from a stabilized external pancreatic fistula as a result of surgical treatment for severe acute pancreatitis in 12 cases, chronic pancreatitis in 3, duodenopancreatectomy in 1, and islet cell tumor enucleation in 1. The surgical repair consisted of precise identification of the fistula tract around the drainage tube and its anastomosis with a Roux-en-Y jejunal loop (fistulojejunostomy). The surgical mortality was nil, and the postoperative outcome was uneventful in 12 patients. Four patients experienced surgical complications, all of which were treated conservatively. After a median follow-up of 93 months, 14 patients are still alive and healthy, 1 had died of neoplastic cachexia, and 2 were lost to follow-up. In our experience, fistulojejunostomy appears to be safe, easy to perform, and curative.

Acute Disease↗

Intra-arterial chemotherapy for unresectable pancreatic cancer.

BACKGROUND: A phase II trial of a new intra-arterial chemotherapy regimen for unresectable pancreatic cancer (UPC). PATIENTS AND METHODS: Ninety-six patients with UPC were treated with intra-arterial chemotherapy at three-weekly intervals. The schedule used was FLEC: 5-fluorouracil 1000 mg/m2, folinic acid 100 mg/m2, carboplatin 300 mg/m2; epirubicin 60 mg/m2. RESULTS: The overall response rates by CT-scan evaluation were: 15% partial response (PR), 44% stable disease (SD), 17% progressive disease (PD). The overall median survival was 9.9 months, and 10.6 and 6.8 for UICC stage III and IV, respectively. Pain reduction occurred in 42% of patients. A weight gain > 7% from baseline occurred in 8% of patients. A total of 341 courses of FLEC were administered. Grade 3-4 hematological toxicity was seen in 25% of patients; ematemesis in 4%; grade 3 gastrointestinal toxicity in 3%; and grade 3 alopecia in 16%. One sudden death, a pre-infarction angina, and a transitory ischemic attack were observed. The only complication related to the angiographic procedure was an intimal dissection of the iliac artery. CONCLUSIONS: The intra-arterial FLEC regimen was well tolerated and active. It requires only one day of hospitalization. Efficacy could only be assessed in a randomized study against a gemcitabine containing regimen.

Adenocarcinoma↗

Changes in pancreatic resection for chronic pancreatitis over 28 years in a single institution.

BACKGROUND: Because of advances in knowledge over recent years there is reason to believe that surgical attitudes towards patients with chronic pancreatitis may have changed. METHODS: Some 547 patients were treated surgically for chronic pancreatitis from 1971 to June 1998. Anastomoses were performed in 80 per cent (438 patients) and resections in 20 per cent (109 patients). Indications and type of operation were analysed, as were mortality and morbidity rates and long-term follow-up results, in patients undergoing resection both over the period as a whole and after dividing the series into two subperiods of 14 years. RESULTS: In the second 14-year period, there was a significant reduction in the percentage of resections compared with anastomoses (28 per cent (69 of 244 patients) versus 13 per cent (40 of 303); P < 0.0001), and a significant change in the type of resection with a substantial increase in resections of the head compared with those of the body and tail. Statistically significant reductions occurred in operating times, number of units of blood transfused (mean(s.d.) 4.7(3.6) versus 1.2(1.6) units; P = 0.0001) and mean hospital stay (18 versus 14 days for pylorus-preserving and 12 versus 8 days for left pancreatectomy with splenectomy; P < 0. 01); mortality and morbidity rates also tended to decrease, but not significantly. CONCLUSION: A different pattern has emerged over the years as regards both the type and number of resections performed.

Adolescent↗

Alcohol intake, cigarette smoking, and body mass index in patients with alcohol-associated pancreatitis.

The differential diagnosis between acute and chronic alcohol-associated pancreatitis is often difficult or impossible at onset of the disease. A study was conducted to determine possible relationships between patients suffering from a first episode of acute alcoholic pancreatitis and patients with unequivocal chronic alcoholic pancreatitis, comparing age, drinking and smoking habits, and body mass index (BMI). Two groups of men were considered. The first group consisted of 67 patients with a diagnosis of acute alcohol-associated pancreatitis in the absence of other potential pathogenic factors; in this group, 48 of the 56 patients surviving the acute attack were submitted to imaging studies for a median period of 9 years. The second group consisted of 396 patients with chronic alcoholic pancreatitis with a median follow-up period of 12 years. The variables that differed significantly in the two groups were BMI (p < 0.009) and number of smokers (p < 0.001). Logistic regression analysis selected only BMI with an odds ratio of 1.19 (95% CI, 1.07-1.33; p < 0.00015) in favor of acute alcoholic pancreatitis. In male patients, from an epidemiologic standpoint, only smoking habits and BMI are significant differences at clinical onset between the two types of pancreatitis.

Acute Disease↗

Intraductal papillary mucinous tumors of the pancreas. Verona University Pancreatic Team.

METHODS: Literature is thoroughly reviewed and compared to our own experience. RESULTS: Clinical history data do not appear to be useful in differentiating between benign and malignant cases. Usually IPMT patients are older than individuals suffering from chronic obstructive pancreatitis and tend to drink and smoke less. Malignant forms of IPMT are more frequently associated with diabetes, and pain seems to be more frequent in benign cases, although these findings are not confirmed in all reports. Also, laboratory tests are of little use, whereas imaging findings currently enable us to reach a correct diagnosis in about 70% of cases without differentiating in a reliable and definitive way the benign or malignant nature of the neoplasm. The WHO classification appears to be related to the different prognosis. Surgery, whenever possible, is the gold standard treatment. CONCLUSION: IPMT are a recent established clinical entity embracing a spectrum of lesions ranging from benign to malignant infiltrating cases. The only recognized radical treatment is surgery. Despite diagnostic capacity based on clinical presentation and imaging techniques has becoming increasingly refined we are still incapable of identifying the different degree of malignancy preoperatively, if any. The lengthy mean survival after resection confirm the high potential cure rate of IPMT of the pancreas.

Adenocarcinoma, Mucinous↗