Chronic Pancreatitis: Landmark Papers, Management Decisions, and Future

On May 16, 2015 at the invitation of the American Gastroenterological Association Institute Council E.P.D. presented a state-of-the-art lecture at Digestive Disease Week 2015. The aims were to discuss a selection of landmark papers in chronic pancreatitis (CP) that influence modern management and to conclude by suggesting some future directions. This is based on that presentation. We will specifically review the following: duct anatomy and pancreas divisum, description of chronic relapsing pancreatitis and its differentiation from recurrent acute pancreatitis and established CP (ECP), natural histories and gene discoveries of alcoholic, idiopathic and hereditary pancreatitis, development of pancreatic cancer in CP, exocrine pancreatic insufficiency and calculation of dose and delivery of enzymes, endoscopic ultrasonography, and autoimmune pancreatitis. With some exceptions, we exclude basic science and surgery.

Chronic pancreatitis

PURPOSE OF REVIEW

We review selected important clinical observations reported in 2012.

RECENT FINDINGS

Celiac disease is a risk factor for pancreatitis. Patients with recurrent acute pancreatitis likely have chronic pancreatitis, do not benefit from pancreatic sphincterotomy, and may not benefit from biliary sphincterotomy. Analysis of endoscopic ultrasonography (EUS) images with an artificial neural network (ANN) program may improve chronic pancreatitis diagnosis compared with clinical interpretation of images. In a multicenter, randomized controlled trial of chronic pancreatitis patients, 90 000 USP U of pancreatin with meals decreased fat malabsorption compared with placebo. Detection of visceral pain in chronic pancreatitis predicts pain relief from various treatments, but nonvisceral pain due to altered central pain processing may respond to agents such as pregabalin. Predictors of surgical pain relief include onset of symptoms less than 3 years and preoperatively no opioid use and less than five endoscopic procedures. Total pancreatectomy for presumed painful chronic pancreatitis remains controversial.

SUMMARY

Celiacs are at risk for pancreatitis. The diagnosis of chronic pancreatitis may be enhanced by ANN analysis of EUS imaging. Treatment of fat malabsorption requires 90,000 USP U of lipase with meals. Relief of pain from organ directed treatment of chronic pancreatitis may depend upon timing of interventions and whether pain is visceral or nonvisceral.

Chronic pancreatitis

PURPOSE OF REVIEW

We review important new clinical observations in chronic pancreatitis made in the past year.

RECENT FINDINGS

Tropical pancreatitis associates with SPINK1 and/or CFTR gene mutations in approximately 50% of patients, similar to the frequency in idiopathic chronic pancreatitis. Corticosteroids increase secretin-stimulated pancreatic bicarbonate concentrations in autoimmune pancreatitis (AIP) by restoring mislocalized CFTR protein to the apical ductal membrane. Most patients with asymptomatic hyperenzymemia have pancreatic lesions of unclear significance or no pancreatic lesions. Common pitfalls in the use of diagnostic tests for exocrine pancreatic insufficiency (EPI) confound interpretation of findings in irritable bowel syndrome and severe renal insufficiency. Further study is needed to improve the accuracy of endoscopic ultrasonography (EUS) to diagnose chronic pancreatitis. Celiac plexus block provides short-term pain relief in a subset of patients.

SUMMARY

Results of this year's investigations further elucidated the genetic associations of tropical pancreatitis, a reversible mislocalization of ductal CFTR in AIP, the association of asymptomatic pancreatic hyperenzymemia with pancreatic disorders, limitations of diagnostic tests for EPI, diagnosis of chronic pancreatitis by EUS and endoscopic pancreatic function testing and treatment of pain.

New advances in acute pancreatitis

PURPOSE OF REVIEW

We endeavor to review important new advances in acute pancreatitis made in the past year. We focused on clinical aspects of acute pancreatitis, which contained new observations or insights into new or old concepts. For experimental acute pancreatitis we refer readers to a recent comprehensive review.

RECENT FINDINGS

Recently, case fatality rates of acute pancreatitis have stabilized; carbohydrate-deficient transferrin was shown to predict alcoholic acute pancreatitis; idiopathic chronic pancreatitis or occult cholelithiasis have been associated with 'recurrent acute pancreatitis' in most patients; and cystic fibrosis transmembrane conductance regulator genetic mutations were frequently found (10-50%) in patients with recurrent acute pancreatitis. In addition, alcohol was shown to increase the risk of pancreatic necrosis regardless of the cause of acute pancreatitis. Persistent organ failure and multiple organ dysfunction syndrome but not necessarily extent of necrosis were demonstrated to predict increased mortality in acute pancreatitis. Chemoprevention of post-endoscopic retrograde cholangiopancreatography acute pancreatitis remains unproven. Enteral feeding has been strongly recommended in severe acute pancreatitis. Finally, data are lacking for routine, prophylactic antibiotic administration to all patients with pancreatic necrosis.

SUMMARY

We reviewed studies this past year that further characterize the epidemiology, etiology and risk stratification of acute pancreatitis. Evolving areas include chemoprevention of post-endoscopic retrograde cholangiopancreatography acute pancreatitis and enteral feeding and antibiotics in severe acute pancreatitis. We await translation of novel therapies from the bench to bedside.

Effect of triglyceride structure on fecal excretion of 13C-labeled triglycerides

OBJECTIVE

The aim of this work was to determine the effects of specific changes in the structure of (13)C-labeled triglyceride (TG*) on its fecal excretion relative to total stool fat excretion determined simultaneously in patients with reduced exocrine pancreatic function.

METHODS

A series of 47 studies were conducted in 26 young cystic fibrosis (CF) patients and 11 adult patients with chronic pancreatitis over a five year period. Each test consisted of ingesting a single high fat test meal containing both (13)C-labeled triglyceride (TG*) and dysprosium chloride (DyCl(3)) a nonabsorbable marker of intestinal transit; in most studies the food colorant brilliant blue (FD&C blue #1) was administered along with the DyCl(3). The TG*s tested were: P*P*P* = TRIPALMITIN-1,1,1-(13)C(3); SO*S = 2-OCTANOYL-1,3-DISTEARIN-2-octanoyl-1,2-(13)C(2); and P*LP* = 2-LAURYL-1,3-DIPALMITIN-dipalmitoyl-1,1,2,2-(13)C(4). Ingestion of the test meal was followed by collection of individual stools for at least 72 hours. Stools were analyzed for (13)C-Excess ((13)C*), total fat, and Dy.

RESULTS

Excretion of P*LP* showed a high degree of linear correlation with stool fat (r(2) = 0.924) over a wide-range of fecal fat values. Excretion of SO*S was also significantly correlated with stool fat, but its excretion was less than 10% at all levels of steatorrhea and the slope of the regression line relating TG* excretion to stool fat was some four to five times smaller than observed for P*LP*. Fecal excretion of P*P*P* was highly correlated with stool fat (r(2) = 0.941) in patients with moderate steatorrhea (<25 g fat/24 hours) and the slope of the regression line (3.20) was considerably greater than for P*LP*. Only results from those studies in which stool collections were complete (Dy excretion >90%) were utilized in the statistical comparisons (36 of 47 studies).

CONCLUSIONS

The observed highly significant linear correlation between P*LP* and stool fat over the entire range of steatorrhea suggests that P*LP* excretion may be a suitable surrogate for fecal fat in patients with reduced exocrine pancreatic function. Because fecal excretion of TG* administered as described can be accurately determined by sampling only two visually marked stools, development of a noninvasive test to replace the current 72-hour stool fat test using this approach is possible. Use of other engineered TG*s and/or labeled fatty acids, may provide a method for non-invasive in vivo assessment of the specific defect(s) leading to steatorrhea in other patient groups.

A prospective randomized trial comparing standard pancreatoduodenectomy with pancreatoduodenectomy with extended lymphadenectomy in resectable pancreatic head adenocarcinoma

BACKGROUND

To compare operative morbidity, mortality, quality of life, and survival after pancreatoduodenectomy (PD) versus pancreatoduodenectomy with extended lymphadenectomy (PD/ELND) in patients with resectable pancreatic cancer.

METHODS

From May 1997 to July 2003 there were 132 patients with biopsy examination-proven or suspected adenocarcinoma of the pancreatic head who agreed to participate in a single-institution, prospective, randomized trial. If resectable at operation, patients then were randomized to standard PD (40 patients) or PD/ELND (39 patients). Quality of life was assessed by using the Functional Assessment of Response to Cancer Therapy specific to the pancreas. Morbidity, mortality, and survival were analyzed.

RESULTS

Demographics and pathologic characteristics for both groups were similar. When comparing PD/ELND with standard PD, the median operating time was greater for the PD/ELND group (7.6 h vs 6.2 h, P < .01), blood transfusion more likely (44% vs 22%, P < .05), and the median number of lymph nodes resected was greater (36 vs 15 nodes, P < .01). Morbidity and mortality rates were comparable. Median durations of stay were 11 and 10.5 days (P = NS), respectively. There were no significant differences in 1-year (71% vs 82%), 3-year (25% vs 41%), 5-year (16.5% vs 16.4%), and median (19 vs 26 mo) survival (P = .32). At 4 months postoperatively, diarrhea, body appearance, and bowel control scored lower on the Functional Assessment of Response to Cancer Therapy specific to the pancreas after PD/ELND (P < .05).

CONCLUSIONS

Although a much larger study would have more power to compare statistically the survival between groups, both the decrement in quality of life and similar studies showing no survival difference make PD/ELND unattractive for further prospective investigation.

Chronic pancreatitis

PURPOSE OF REVIEW

As in our previous reviews, we endeavor to review important new observations in chronic pancreatitis made in the past year. We included articles, including review articles, only if they contained new observations or readdressed old questions and provided new insights into old and new concepts.

RECENT FINDINGS

Important observations include the following: (1) Strong association between cystic fibrosis transmembrane regulator dysfunction/mutations and 'recurrent acute pancreatitis', particularly in patients with pancreas divisum (2) Pancreas divisum may be incidental finding in recurrent acute pancreatitis (3) Smoking increases risk of chronic pancreatitis (4) Coxsackie B virus may increase severity of alcoholic chronic pancreatitis (5) CD4+ T cells and an immune reaction against amylase may play a role in pathogenesis of autoimmune pancreatitis (6) 2-(18F)-Fluro-2-deoxy-D-glucose positron emission tomography might be useful to detect pancreatic cancer in chronic pancreatitis patients at risk for developing pancreatic cancer, but contrast-enhanced Doppler ultrasound or endosonography may be as sensitive and better than contrast enhanced computed tomography (7) Superiority of surgery vs endotherapy for long term pain relief and weight gain in painful chronic pancreatitis (8) Early treatment of pain and malabsorption may improve life quality (9) Antifibrogenesis and fibrolytic agents as potential therapies.

SUMMARY

Ongoing basic and clinical research this past year has further characterized genetic, molecular and clinical aspects of chronic pancreatitis. The advent of predictable and lasting treatments of chronic pancreatitis is most likely to appear on the wings of carefully conducted studies targeting genetic and molecular mechanisms of chronic pancreatitis, particularly pancreatic fibrogenesis.

'Good mentorship is invaluable' - an interview with Dr. Eugene P. DiMagno. Interview by Martin E. Fernandez-Zapico

Dr. DiMagno is internationally renowned for his contributions to almost all areas of pancreatology. He helped pioneer discoveries about normal pancreatic function, enzyme-based treatment of exocrine pancreatic insufficiency as well as methods of diagnosing pancreatitis and pancreatic cancer, including the development of function tests and endoscopic ultrasound. Answering Martin Fernandez-Zapico's questions, he stresses the importance of good mentorship and gives us a glimpse of his life and work.

Chronic pancreatitis

PURPOSE OF REVIEW

Clinicians are learning more about chronic pancreatitis but are entering an era of some confusion, primarily driven by uncovering new etiologies of chronic pancreatitis. Ideally, this knowledge will lead to better diagnosis and treatment, and abandonment of ill-conceived treatments. In contrast with previous reviews, this review highlights select contributions this year that may develop into true advances in chronic pancreatitis.

RECENT FINDINGS

Small steps have been made to understand better the molecular basis of chronic pancreatitis. Diagnosis of early chronic pancreatitis remains challenging. Rapid diagnosis by combining endoscopy and a direct stimulatory test of pancreatic function may lead to more widespread use of function testing, but this test is not ready for clinical use. Application of microarray and proteomic technologies may aid future diagnosis of chronic pancreatitis. The failure to account clearly for the phenotype of patients with chronic pancreatitis may confound delineating the etiologies of chronic pancreatitis. Clinical description and studies of autoimmune pancreatitis have led to the realization that steroids are an effective treatment for this form of chronic pancreatitis. Genetic-based studies have provided insight into the pathogenic mechanisms of chronic pancreatitis. Investigation of the role of stellate cells, an essential component fibrogenesis, has led to identification of potential novel treatments for chronic pancreatitis.

SUMMARY

Ongoing basic and clinical research this past year has characterized further the histologic, genetic, molecular, and clinical aspects of chronic pancreatitis, efforts that may translate into novel therapies once well-designed, controlled studies have been performed.

Primer on medical genomics. Part XIII: Ethical and regulatory issues

Ethics in the new genomics era has become an increasingly complex subject that often arouses passion and confusion. Although 50 years have elapsed since the elucidation of the DNA molecule, the recent near-complete sequencing of the human genome has sharply accelerated the incorporation of genetics into the medical mainstream. Along with these scientific advances, however, have surfaced challenges, liabilities, and issues regarding the processing and management of genetic information as they relate to core ethical principles such as respect for autonomy, beneficence, nonmaleficence, and justice. Institutions and state and federal governments have initiated systematic and preemptive measures in education, resource development, and protective legislation to address these cardinal ethical issues. Genetic research is also being scrutinized carefully by institutional review boards, an activity that should not be perceived as being adversarial but rather as a protective shield for investigators and research participants alike. Ultimately, it is hoped that genomics medicine will diminish rather than enhance existing sex-, race-, and socioeconomic class-based inequities in health care access and delivery. This article describes some but not all aspects of the ethical, legal, and social implications of genomics in clinical practice.

Chronic pancreatitis

PURPOSE OF REVIEW

We are beginning to better understand the causes of chronic pancreatitis. This knowledge will hopefully lead to better diagnosis and treatment and abandonment of ill-conceived treatments. This review highlights contributions that moved the field toward these goals in the past year.

RECENT FINDINGS

Small steps have been made toward a better understanding of the molecular basis, particularly genetic causes, of the forms of chronic pancreatitis. Investigation of the role of stellate cells, an essential component of the fibrosis of chronic pancreatitis, has led to the finding that lovastatin inhibits stellate cell activation and could surface as a novel treatment of chronic pancreatitis. The clinical description of autoimmune pancreatitis has led to the realization that steroids are effective treatment for this form of chronic pancreatitis. Other treatments such as extracorporeal shock wave lithotripsy and endoscopic treatments have not been proved, because no controlled studies support these treatments over other treatments. The diagnosis of chronic pancreatitis may be enhanced by the new imaging technique of electronic pancreatoscopy whereby a 2.1-mm diameter scope can be advanced into the pancreatic duct through a duodenoscope. However, the data are too preliminary at this time to advocate this imaging procedure. A potential new endoscopic pancreatic function test may lead to more widespread use of function testing, but this test is not perfected and also cannot be advised for use at present.

SUMMARY

Ongoing basic and clinical research this past year has further characterized the genetic, molecular, and clinical aspects of chronic pancreatitis: efforts that may translate into novel therapies, once well-designed, controlled studies have been performed.

Rapid endoscopic secretin stimulation test and discrimination of chronic pancreatitis and pancreatic cancer from disease controls

BACKGROUND & AIMS

The cholecystokinin (CCK)/secretin pancreatic function tests to diagnose pancreatic exocrine insufficiency are time consuming and invasive. Our aim was to develop a rapid pancreatic function test performed during upper endoscopy that could discriminate between patients with normal from impaired exocrine pancreatic secretion.

METHODS

We prospectively evaluated 412 patients for possible pancreatic diseases. During upper endoscopy, 1 CU/kg of secretin was given intravenously and duodenal juice (collected for 10 min) was assayed for concentrations of bicarbonate and lipolytic and trypsin activity. Final diagnosis was by histology, imaging, and a previously validated scoring system (for chronic pancreatitis). Of 412 patients, 117 patients had normal pancreas, 72 patients had chronic pancreatitis, and 116 patients had pancreatic adenocarcinoma. The remaining 107 patients had miscellaneous disease of the peripancreatic region. In 28 patients we also validated the secretin test with the standard CCK pancreatic function test.

RESULTS

There was no difference between bicarbonate or trypsin concentrations among the groups. Lipolytic concentration was significantly lower in chronic pancreatitis (115 +/- 18) and in pancreatic adenocarcinoma (87 +/- 10) compared with patients with normal pancreas (229 +/- 23; P < 0.03 and P < 0.0001, respectively). The overall accuracy of the endoscopic secretin test was 79%, with positive and negative predictive values of 73% and 85%, respectively. The concentration of lipolytic activity obtained by the endoscopic secretin test in 28 patients correlated moderately well (r = 0.41, P < 0.03) with lipolytic output obtained by the CCK pancreatic function test.

CONCLUSIONS

Lipolytic concentration in duodenal juice after intravenous secretin collected for 10 minutes during upper endoscopy was significantly lower in chronic pancreatitis and pancreatic adenocarcinoma compared with patients with normal pancreas, but was not accurate enough for routine clinical use.

Intraductal papillary mucinous neoplasm: did it exist prior to 1980?

INTRODUCTION

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas was first reported in 1982. It is not clear whether the appearance of this neoplasm is a new epidemic or an old disease previously overlooked.

AIM

To determine whether IPMN existed as a separate entity before 1982.

METHODOLOGY

We reviewed our pathology reports from all cases of pancreatic cancer diagnosed between 1960 and 1980. Pathologic specimens with descriptors--"mucinous," "cystic," or "papillary"--underwent histologic reexamination. Medical records for patients given a new diagnosis of IPMN from this pathologic review were assessed.

RESULTS

Eighty-four of more than 4,000 pathology reports reviewed contained a key word triggering histologic review. IPMN was identified in 21 patients. Patients had a mean age of 63 years (range, 44-77 years) with symptoms present for a mean of 76 months (median, 15 months; range, 1-516 months). Reported symptoms were abdominal pain in 17, jaundice in 13, weight loss in 12, and pancreatic insufficiency in 7 patients. On pathologic review, the in situ component was graded as adenoma in 4, borderline in 4, and carcinoma in 13. Parenchymal invasion was present in 11/21 (52%). Excluding four postoperative mortalities, mean time to death was 58 months (median, 15 months; range, 2-264 months). Seven patients died of IPMN, 4 of other causes without evidence of recurrence, and 6 of unknown causes.

CONCLUSIONS

IPMN existed in its current known form prior to 1982. Our study cannot determine whether the prevalence or incidence has changed since that time.

Study of recurrence after surgical resection of intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND & AIMS

The aim of this study was to determine recurrence and long-term survival after resection of pancreatic intraductal papillary mucinous neoplasm and to correlate recurrence and survival with histology, extent of resection, and duration of follow-up.

METHODS

A single pathologist, without knowledge of previous interpretations of histology or clinical data, retrospectively reviewed and classified 113 resected intraductal papillary mucinous neoplasms as invasive carcinoma (n = 40) or as noninvasive neoplasms (adenoma, borderline, or carcinoma in situ; n = 73). Data on recurrence (locoregional or metastatic), follow-up, and cause of death were obtained from patient records and/or by contacting patients and their physicians.

RESULTS

In invasive intraductal papillary mucinous neoplasm, recurrence was similar after partial pancreatectomy (18/27; 67%) and total pancreatectomy (8/13; 62%) and occurred within 3 years of resection in 91%. Among noninvasive neoplasms, 5 of 60 (8%) recurred after partial pancreatectomy (median follow-up, 37 months); none recurred after total pancreatectomy (n = 13; median follow-up, 32 months). Recurrence after resection in noninvasive neoplasms was diagnosed after a median of 40 months (range, 23-75 months); recurrence was noninvasive in 3 and invasive cancer in 2. Five-year survival was better for noninvasive compared with invasive intraductal papillary mucinous neoplasm (84.5% vs. 36%; P < 0.001).

CONCLUSIONS

Invasive intraductal papillary mucinous neoplasm recurs frequently even after a complete "curative" resection and portends poor survival. In contrast, noninvasive intraductal papillary mucinous neoplasm recurs infrequently after resection, and survival is excellent regardless of the degree of epithelial dysplasia in the tumor.

Invasive cancer and survival of intraductal papillary mucinous tumors of the pancreas

OBJECTIVES

Intraductal papillary mucinous tumor (IPMT) is frequently associated with pancreatic cancer. We hypothesized that IPMT progresses to invasive cancer with K-ras mutations as an early event, and that invasive cancer affects survival. We compared survival after resection and determined whether K-ras mutations predicted survival in IPMT patients without or with invasive cancer.

METHODS

Records of 47 patients with IPMT who were seen between 1983 and 1998 were reviewed retrospectively in 15 cases and prospectively in 32. All histological material was reviewed to confirm the diagnosis of IPMT and to assess invasion. Kaplan-Meier survival curves were analyzed by the log-rank test. The chi2 test was used for differences in K-ras between groups.

RESULTS

There were 30 men and 17 women, with a mean age of 65 yr (range 36-90 yr). Of the patients, 26 had IPMT without invasive cancer and 19 had IPMT with invasion. Tissue diagnosis was available in 45 patients. K-ras was analyzed in 40 patients. Mutations were present in 15 of 23 patients (65%) without invasive cancer and in 14 of 17 patients (82%) with invasive cancer (p = ns). At 2.5 yr, the overall cumulative survival of IPMT patients without invasive cancer was 94% compared to 24% of patients with invasive cancer (p < 0.001). The 5-yr survival of IPMT patients without invasive cancer was 94%. K-ras mutations did not correlate with survival.

CONCLUSIONS

Invasive cancer in IPMT reduces the 2.5-yr survival after surgery from 93% to 24%. K-ras mutations occur before invasive cancer, and do not predict postoperative survival.

Chronic pancreatitis

An increasing number of novel mutations are associated with chronic pancreatitis. Some cause a high-penetrance, autosomal dominant type of clinical picture (eg, mutations at codons 29 and 122 of the cationic trypsinogen gene), whereas others have a low penetrance or are frequent in the general population (eg, mutations in Kazal type 1 [SPINK1] and in codons 16, 22, and 23 of the cationic trypsinogen gene) and act as disease modifiers. The results of recent studies indicate that smoking adversely affects the course and complications of chronic pancreatitis (more frequent and faster rate of calcification and higher risk of development of pancreatic cancer). Thus, regardless of the cause of chronic pancreatis, patients with this condition should not smoke. Using current diagnostic criteria, the accuracy of endoscopic ultrasound for the diagnosis of chronic pancreatitis is not good. For example, 39% of dyspeptic persons without any other evidence of chronic pancreatitis fulfilled the endoscopic ultrasound criteria for chronic pancreatitis. Diabetes frequently occurs in chronic pancreatitis, but it is not prevented or increased by pancreatic surgery. Islet cell autotransplantation holds promise for the prevention of diabetes in patients requiring total pancreatectomy if the pancreas is not extensively fibrotic. Splenic vein occlusion is present in 7% of patients undergoing surgery for chronic pancreatitis, but fewer than one fifth of these patients have variceal bleeding before or after surgery.

Islet amyloid polypeptide is not a satisfactory marker for detecting pancreatic cancer

BACKGROUND & AIMS

Islet amyloid polypeptide (IAPP) levels are elevated in pancreatic cancer and may be a useful marker of pancreatic cancer-associated diabetes. The aim of this study was to compare the sensitivity and specificity for pancreatic cancer of IAPP with that of CA19-9, examine clinical characteristics of diabetes in pancreatic cancer, and define the relationship of IAPP to diabetes of pancreatic cancer.

METHODS

Fasting serum glucose, IAPP, and CA 19-9 were measured in 130 subjects with pancreatic cancer, 250 subjects with other pancreatic and peripancreatic diseases, and 116 controls. In pancreatic cancer patients, we noted tumor stage and the presence and duration of diabetes.

RESULTS

IAPP was markedly elevated in pancreatic cancer, especially in patients with diabetes. However, the sensitivity of IAPP for pancreatic cancer was less than that of CA 19-9 (40% vs. 75%; P < 0.001). Diabetes was present in 46% of pancreatic cancers and 55% of resectable tumors. In pancreatic cancer with diabetes, the sensitivity of IAPP was only 50%. In resectable cancer it was 27%.

CONCLUSIONS

IAPP is elevated in pancreatic cancer but is not sensitive enough to replace or complement existing tests. Diabetes occurs early and frequently in pancreatic cancer. Development of a sensitive and specific marker for pancreatic-associated diabetes might lead to diagnosis of resectable pancreatic cancer.

Utility of endoscopic ultrasonography in endoscopic drainage of pancreatic pseudocysts in selected patients

OBJECTIVES

To determine the effect of endoscopic ultrasonography (EUS) on endoscopic drainage of pancreatic pseudocysts and to determine patency with fistula dilation and placement of multiple stents.

PATIENTS AND METHODS

Between September 1995 and January 1999, 19 patients underwent endoscopic drainage of pancreatic pseudocysts, 17 of whom were assessed by EUS before drainage. Radial EUS scanning was used to detect an optimal site of apposition of pseudocyst and gut wall, free of intervening vessels. A fistula was created with a fistulatome, followed by balloon dilation of the fistula tract. Patency was maintained with multiple double pigtail stents. The primary goal of this retrospective study was to determine whether EUS affected the practice of endoscopic drainage of pancreatic pseudocysts.

RESULTS

In 3 patients, drainage was not attempted based on EUS findings. In the other 13 patients (14 pseudocysts), creation of a fistula was successful on 13 occasions, and no immediate complications occurred. However, 1 patient subsequently developed sepsis that required surgery. All other patients were treated with balloon dilation, multiple stents, and antibiotics, with no septic complications. Of 14 pseudocysts (in 13 patients), 13 (93%) resolved.

CONCLUSIONS

Results of EUS may alter management of patients considered for endoscopic drainage of pancreatic pseudocysts. Endoscopic ultrasonography was useful for selecting an optimal and safe drainage site. The combination of balloon dilation, multiple stents, and antibiotics appears to resolve pancreatic pseudocysts without septic complications.

Utility of endoscopic ultrasonography in endoscopic drainage of pancreatic pseudocysts in selected patients

OBJECTIVES

To determine the effect of endoscopic ultrasonography (EUS) on endoscopic drainage of pancreatic pseudocysts and to determine patency with fistula dilation and placement of multiple stents.

PATIENTS AND METHODS

Between September 1995 and January 1999, 19 patients underwent endoscopic drainage of pancreatic pseudocysts, 17 of whom were assessed by EUS before drainage. Radial EUS scanning was used to detect an optimal site of apposition of pseudocyst and gut wall, free of intervening vessels. A fistula was created with a fistulatome, followed by balloon dilation of the fistula tract. Patency was maintained with multiple double pigtail stents. The primary goal of this retrospective study was to determine whether EUS affected the practice of endoscopic drainage of pancreatic pseudocysts.

RESULTS

In 3 patients, drainage was not attempted based on EUS findings. In the other 13 patients (14 pseudocysts), creation of a fistula was successful on 13 occasions, and no immediate complications occurred. However, 1 patient subsequently developed sepsis that required surgery. All other patients were treated with balloon dilation, multiple stents, and antibiotics, with no septic complications. Of 14 pseudocysts (in 13 patients), 13 (93%) resolved.

CONCLUSIONS

Results of EUS may alter management of patients considered for endoscopic drainage of pancreatic pseudocysts. Endoscopic ultrasonography was useful for selecting an optimal and safe drainage site. The combination of balloon dilation, multiple stents, and antibiotics appears to resolve pancreatic pseudocysts without septic complications.

Gastric acid suppression and treatment of severe exocrine pancreatic insufficiency

Adding either H(2)-receptor antagonists (cimetidine or ranitidine) or proton pump inhibitors to an adequate amount of lipolytic activity improves fat malabsorption in most cases and abolishes steatorrhoea in up to 40% of children and adults with cystic fibrosis and in adults with chronic pancreatitis. Acid suppression improves fat absorption because the resultant increase in pH within the upper gastrointestinal tract improves the survival of lipolytic activity, reduces duodenal volume flow and prevents the precipitation of bile acids. These effects increase the concentration of intraduodenal lipolytic activity and promote the aggregation of bile acids and the micellar solubilization of lipid. The amount of lipase that should be recommended is controversial, but we interpret our studies as indicating that at least 90 000 United States Pharmacopeia (USP) units should be ingested with meals. This amount of lipolytic activity taken with an agent that suppresses gastric acid secretion improves fat absorption in most patients and may even abolish steatorrhoea.

Protection of research subjects with emphasis on protocols involving radiation

Approval by an institutional review board (IRB) or human studies committee must be obtained prior to conducting human subject research. Historically this was not the case, and human subjects were injured as a result. Because there has been and still remains an inevitable conflict of interest for researchers, instititions that perform human research must follow regulations designed to protect human subjects contained in the Code of Federal Regulations, if the research is federally funded. Two federal agencies provide oversight for IRB activities: the Food and Drug Administration (FDA) and a National Institutes of Health Office for Human Research Protection (OHRP), formerly the Office for Protection from Research Risks (OPRR). These agencies are charged with the implementation of rules related to ethical and legal obligations of researchers and their institutions. The institution's role, by means of an IRB, is to adhere to principles of the Belmont Report and to set forth ethical principles, policies, and procedures for protecting the rights and welfare of human subjects. The researchers' role is to conduct their research ethically while maximizing benefits and minimizing harm. Studies involving radiation exposure of human subjects add another level of risk that must be evaluated by an IRB with assistance of a radiation expert or radiation safety committee (RSC). This paper will look at regulatory aspects of human research, IRB responsibilities overall and as they relate to radiation exposure of subjects, and the role of the RSC.

The effect of small amounts of alcohol on the clinical course of chronic pancreatitis

OBJECTIVE

To investigate the hypothesis that an increasing intake of alcohol accelerates the course of chronic pancreatitis.

PATIENTS AND METHODS

In this retrospective record analysis and subsequent prospective follow-up of 372 patients with chronic pancreatitis, we separately compared the clinical course of chronic pancreatitis among the following patients: those with early-onset idiopathic chronic pancreatitis and no alcohol intake (group A [n=25]) and those with late-onset idiopathic chronic pancreatitis and no alcohol intake (group B [n=41]), low alcohol intake (< 50 g/d) (group C [n=57]), and high alcohol intake (> or = 50 g/d) (group D [n=249]). From medical records, physical examinations, questionnaires, death certificates, or autopsy reports, we obtained information on sex, age, signs and symptoms (pain severity, calcification, endocrine and exocrine insufficiency), complications, surgery, and survival.

RESULTS

Group D had the highest percentage of men (72%). At the onset of chronic pancreatitis, patients in group A were significantly younger than those in groups B, C, and D (P<.05), and severity of pain was significantly greater in patients in group A than in groups B, C, and D (P<.05). The percentage of patients who eventually developed endocrine or exocrine insufficiency was similar in all groups. Among patients in groups B, C, and D, an increasing intake of alcohol from zero to less than 50 g/d to more than 50 g/d was associated with earlier inception of disease (P<.001). Pain prevalence at onset was less in group B patients than in patients in groups C and D (P<.05). Intake of a large amount of alcohol (group D) shortened time to calcification and survival (P<.05). In addition, patients in group D had more complications (fistulas, pseudocysts, abscesses, and biliary obstruction) (P<.05) than those in groups A and B. More patients in group A underwent pancreatic surgery compared with patients in groups B and C.

CONCLUSIONS

Among patients with onset of chronic pancreatitis after age 35 years, alcohol intake, even less than 50 g/d, induced earlier disease characterized by more frequent severe pain, calcification, and complications. Intake of large amounts of alcohol (> or = 50 g/d) reduced time to calcification and death.

Chronic pancreatitis

In the past year, there has been at least one important clinical paper that sheds light on the character and natural history of painful chronic pancreatitis, which has important clinical implications. In addition, several novel mutations have been described in the cationic trypsinogen gene in patients with hereditary pancreatitis. The mechanism by which these mutations cause pancreatic disease remains speculative. The diagnosis of early chronic pancreatitis is controversial. A novel noninvasive pancreatic function test (measurement of postprandial APOB-48) was reported but is unlikely to be a sensitive test of pancreatic function. Pancreatic fibrosis is frequently seen in alcoholics without chronic pancreatitis, and this makes it difficult to interpret the findings on endoscopic ultrasonogram. Recent studies highlight the difficulty in abolishing pancreatic steatorrhea. Recently fibrosing colonopathy in adult patients has been reported. Extracorporeal shockwave lithotripsy combined with endoscopic therapy failed to benefit patients with calcific chronic pancreatitis.

Cigarette smoking increases the risk of pancreatic calcification in late-onset but not early-onset idiopathic chronic pancreatitis

An association exists between cigarette smoking and pancreatitis owing to alcohol. We determined whether cigarette smoking affected the course of pancreatic calcification and insufficiency in idiopathic chronic pancreatitis. Medical records were analyzed of 24 persons with early- and 42 with late-onset idiopathic chronic pancreatitis who were diagnosed between 1976 and 1982 and then followed prospectively until 1985. Smoking equaled >5 pack-years before calcification or insufficiency or last follow-up. Mean follow-up after onset of chronic pancreatitis was 27 and 13 years in early- and late-onset idiopathic chronic pancreatitis, respectively. Incidence of calcification in the two groups was 58 and 43%, respectively. In early-onset idiopathic chronic pancreatitis, smokers and nonsmokers developed calcification at a similar rate and frequency (58%). In late-onset idiopathic chronic pancreatitis, smokers developed pancreatic calcifications faster (p < 0.001) and more frequently (83 vs. 13%, p < 0.001) than nonsmokers. The association between smoking and pancreatic calcification was independent of gender, body mass index, and exocrine or endocrine insufficiency. Smoking did not affect development of exocrine or endocrine insufficiency. Cigarette smoking increases the risk of pancreatic calcification of late- but not of early-onset idiopathic chronic pancreatitis. These data support encouraging cessation of smoking in chronic pancreatitis.

Acute pancreatitis in the postpartum period: a population-based case-control study

OBJECTIVE

To determine relationships among pregnancy (during and postpartum), acute pancreatitis, and gallstones.

PATIENTS AND METHODS

In this retrospective population-based case-control study, we identified all 12- to 50-year-old Rochester, Minn, females diagnosed between 1976 and 1991 as having acute pancreatitis (cases). For each case, we matched 4 women of the same age (+/- 6 years) with no history of acute pancreatitis (controls). Acute pancreatitis was defined as associated with pregnancy if it occurred from 10 months prior to delivery to delivery and with the postpartum period if it occurred within 10 months of the date of delivery. Logistic regression was used to assess associations between pregnancy-related acute pancreatitis, age, gallstone occurrence, and alcohol use.

RESULTS

In a cohort of 61 women who developed acute pancreatitis and 244 controls, the relative risk for acute pancreatitis associated with pregnancy was 1.43 (95% confidence interval, 0.61-3.40). All 10 cases of acute pancreatitis associated with pregnancy occurred in the postpartum period. Gallstones were present in 6 of them compared with 13 of 51 women with non-pregnancy-related acute pancreatitis (P < .05). Women with postpartum-related pancreatitis were younger than those with non-pregnancy-related pancreatitis (mean, 28 vs 36 years; P < .05). Alcohol was not associated with pregnancy-related pancreatitis.

CONCLUSIONS

Acute pancreatitis during the postpartum period is not directly related to pregnancy but is associated with gallstones and occurs in younger women.

Clinical and pathologic correlation of 84 mucinous cystic neoplasms of the pancreas: can one reliably differentiate benign from malignant (or premalignant) neoplasms?

OBJECTIVE

To determine whether the long-term behavior of cystic mucinous neoplasms of the pancreas could be predicted using a novel, precisely defined classification of benign mucinous cystadenomas, noninvasive proliferative cystic mucinous neoplasms, and invasive mucinous cystadenocarcinomas. The primary interest was to obtain long-term follow-up after complete resection to determine the recurrence rates based on this objective classification.

BACKGROUND

Current understanding is that all cystic mucinous neoplasms of the pancreas are potentially malignant and that mucinous cystadenomas, when completely removed, are biologically benign. Cystadenocarcinomas are thought to be less aggressively malignant than ordinary ductal adenocarcinoma, but reported recurrence rates vary widely and are unpredictable.

METHODS

All patients who underwent "curative" resection for cystic mucinous neoplasms at Mayo Clinic Rochester from 1940 to 1997 were identified. All available pathology slides, gross specimens, and clinical records were reviewed, eliminating patients with inadequate documentation. Neoplasms were reclassified as mucinous cystadenomas, noninvasive proliferative mucinous cystic neoplasms, or invasive cystadenocarcinomas based on specific histologic criteria.

RESULTS

Of 84 patients (70 women, 14 men) with cystic mucinous neoplasms of the pancreas, 54 were classified as cystadenomas, 23 as noninvasive proliferative cystic mucinous neoplasms, and only 7 as cystadenocarcinomas. Recurrent disease developed in none of the 77 patients without invasion, but 5 of the 6 patients surviving resection for cystadenocarcinomas died of recurrent cystadenocarcinoma within 5 years.

CONCLUSIONS

When the neoplasm is completely resected and subjected to adequate histopathologic examination based on these objective criteria, absence of tissue invasion predicts a curative operation and detailed follow-up may be unnecessary. In contrast, a histologic diagnosis of invasive cystadenocarcinoma portends a dismal prognosis, similar to that of typical ductal adenocarcinoma of the pancreas.

AGA technical review on the epidemiology, diagnosis, and treatment of pancreatic ductal adenocarcinoma. American Gastroenterological Association

This literature review and the recommendations therein were prepared for the American Gastroenterological Association Clinical Practice and Practice Economics Committee. The paper was approved by the Committee in March 1999 and by the AGA Governing Board in May 1999.

Pancreatic cancer: clinical presentation, pitfalls and early clues

The diagnosis of pancreatic cancer usually depends upon symptoms; consequently it is late when there is no chance for cure. At this point, pain, anorexia, early satiety, sleep problems and weight loss are present. Back pain also may be prominent, which predicts unresectability and shortened survival after resection. However, earlier recognition of symptoms of pancreatic cancer might improve early detection of the cancer. For example, 25% of patients have symptoms compatible with upper abdominal disease up to 6 months prior to diagnosis and 15% of patients may seek medical attention more than 6 months prior to diagnosis. These symptoms erroneously may be attributed to problems such as irritable syndrome. Symptoms, however, may be less common. For example a quarter of patients with pancreatic cancer may have no pain at diagnosis, and half, particularly those with pancreatic head tumors, may have little pain compared with patients with body-tail tumors. However, if the tumor is suspected because of predisposing conditions, earlier diagnosis may be possible. These conditions include diseases such as chronic pancreatitis, intraductal papillary mucinous tumor (IPMT), and recent onset of diabetes mellitus, particularly if the diabetes occurs during or beyond the sixth decade. In addition inherited syndromes also are associated with an increased risk of pancreatic cancer including familial pancreatic cancer, hereditary pancreatitis, familial adenomatous polyposis syndrome (FAP) and familial atypical multiple mole melanoma (FAMMM) syndrome (hereditary dysplastic nevus syndrome). Of these conditions, recent onset of diabetes may be the best clue and should be included in a clinical profile of patients prior to the onset of symptoms to identify a high-risk group to apply screening strategies for detection of early disease. Contrary to a clinical aphorism that pancreatic cancer patients are elderly, lean and recently may have developed diabetes, we found that patients who develop pancreatic cancer are overweight prior to onset of symptoms compared to controls (body mass index, 28 vs 25). Forty percent had the diagnosis of diabetes made at the time of diagnosis of pancreatic cancer and more patients with a resectable tumor had diabetes (58%) compared to patients with locally unresectable or metastatic disease (37%). Perhaps, screening overweight persons who have new-onset diabetes may lead to a diagnosis of asymptomatic, early, resectable pancreatic cancer.

Early and late onset in idiopathic and alcoholic chronic pancreatitis. Different clinical courses

In summary, a prerequisite for the development of alcoholic pancreatitis would be the specific individual predisposition present in patients with late-onset idiopathic chronic pancreatitis. Furthermore, because the reported prevalence of chronic pancreatitis in patients with heavy alcohol consumption is markedly higher than the prevalence of late-onset idiopathic pancreatitis in the general population, the authors conclude that, in predisposed patients, alcohol consumption promotes the development of pancreatitis and accelerates the manifestation of symptoms and complications. This concept explains the observation that only a minority of severe alcoholics develop chronic pancreatitis. Conversely, in postmortem studies, a substantial proportion of older individuals without premortem evidence of pancreatic disease and no excessive alcohol history have pancreatic morphologic alterations resembling chronic pancreatitis. Thus, in the general population, a considerable number of asymptomatic "carriers," together with an undetected high prevalence of late-onset idiopathic chronic pancreatitis, may exist. In these persons, alcohol consumption might amplify and accelerate preexisting asymptomatic idiopathic pancreatic damage. As a consequence, in a dose-dependent manner, alcohol may lead to an earlier onset of or induce clinically apparent pancreatitis in persons who otherwise might never have had symptoms during their lives.

Acute postprandial gastrointestinal and metabolic effects of wheat amylase inhibitor (WAI) in normal, obese, and diabetic humans

Amylase inhibition has gastrointestinal and metabolic effects that may aid in the treatment of diabetes and obesity. We tested whether 4 g of a commercially available wheat amylase inhibitor (WAI) affected postprandial carbohydrate (CHO) absorption and plasma glucose or hormones. Twelve persons (four lean and four obese nondiabetics and four obese type II diabetics) were studied on 2 separate days. After eating a weight maintenance diet (55% CHO, 20% protein, and 25% fat, as percentage of calories) for 3 days, subjects ate a breakfast containing 650 kcal, the same proportion of nutrients as calories, and in random order, either WAI or no WAI. Breath H2 and plasma glucose and hormones were measured every 15 and 30 min, respectively, for 7 h. WAI decreased the delta peak postprandial plasma glucose concentrations in 10 of 12 subjects (p < 0.05) and increased the breath H2 levels in 11 (p = 0.02); the increases in breath H2 were small, generally <20 ppm. No subject experienced a change in stools, diarrhea, or bloating. In response to WAI, gastric inhibitory peptide decreased (p < 0.05), peptide YY increased (p < 0.05), and there was a trend toward increased human pancreatic polypeptide (p = 0.07). Although WAI delays CHO absorption and reduces peak postprandial plasma glucose concentrations, overall CHO malabsorption is minimal (as reflected by breath hydrogen and hormones) and without symptoms. It, therefore, may be useful in treating type II diabetes mellitus.

Effect of chronic amylase inhibition on pancreatic growth and acinar cell secretory function in rats

Wheat amylase inhibitor (WAI) was given to growing rats to determine whether chronic inhibition of intraluminal amylase activity alters pancreatic growth, pancreatic enzyme composition, and secretory responsiveness to cholecystokinin octapeptide (CCK-OP) and carbachol. For 21 days 13 rats were fed amylase inhibitor (AI) as 2.72% of the weight of their food; 13 were pair-fed controls (PFC), and 12 were controls with free access to food (FAC). Amylase and lipase secretion was measured from isolated pancreatic acini in response to CCK-OP (10(-12)-10(-8) M) and carbachol (10(-8)-10(-3) M). AI and PFC rats had similar food intakes and weight gains, pancreatic weights, and contents of enzymes (amylase, lipase, trypsin, chymotrypsin), protein, and RNA, but these measurements were significantly reduced compared to those of FAC rats. DNA contents per milligram of pancreas and per gram of body weight and amylase/DNA and trypsin/DNA were similar among all groups. Lipase/DNA and chymotrypsin/DNA in AI rats were the same as in PFC rats but significantly lower than in FAC rats. In response to CCK-OP, amylase secretion was similar in all three groups, but in response to carbachol amylase secretion was significantly less in AI compared to PFC and FAC rats. Lipase secretion increased in response to CCK-OP in AI compared to PFC and FAC rats but was similar in all three groups in response to carbachol. Long-term inhibition of intraluminal amylase activity suppresses pancreatic growth and content of enzymes and RNA by reducing food intake and weight gain and also decreases acinar cell secretion of amylase in response to carbachol and increases lipase secretion in response to CCK-OP.

1996 Comfort Symposium on Pancreatic Carcinogenesis

This article summarizes the proceedings of the 1996 Comfort Symposium on Pancreatic Carcinogenesis that took place at the Mayo Clinic in Rochester, Minnesota, September 11-13, 1996. The annual series of Comfort lectures are aimed at discussing leading theories and advanced technological developments in the area of pancreatic research. The goals of this year's symposium were to summarize epidemiologic and experimental findings in the field of pancreatic cancer research, to foster communications among scientists studying this disease, and to identify areas of research that are likely to bridge the gaps between basic science and patient care. The topics discussed included (i) current algorithms for the diagnosis of early pancreatic cancer, (ii) animal and cellular models of pancreatic carcinogenesis, (iii) mechanisms of pain in pancreatic cancer, (iv) the role of signaling cascades and transcription factors in the regulation of pancreatic cell growth and differentiation, (v) methods to study genetic alterations associated with neoplastic diseases, and (vi) recent developments in gene-targeting techniques. The lectures and discussions during the symposium successfully achieved the goals outlined above and resulted in the identification of novel areas of research that may increase our understanding of the etiology and pathogenesis, and lead to early diagnosis and treatment of pancreatic cancer.

Survival of human pancreatic enzymes during small bowel transit: effect of nutrients, bile acids, and enzymes

The activity of pancreatic enzymes declines during aboral intestinal transit. We tested the hypothesis that survival of pancreatic enzyme activities during intestinal transit is affected by amounts or concentrations of calories, nutrients, bile acids, or pancreatic enzymes entering the segments of the small intestine. An oroileal tube was placed in 26 healthy humans. The tube had duodenal, jejunal, and ileal infusion ports for nonabsorbable markers and aspiration ports in the distal duodenum, distal jejunum, and distal ileum. Four infusates of different proportions of protein, fat, and carbohydrate were infused continuously into the duodenum at 40, 90, and 160 kcal/h. Of the nutrients infused into the proximal duodenum, 21 +/- 3, 51 +/- 7, and 39 +/- 5% of fat, protein, and carbohydrate, respectively, were delivered to the distal duodenum. During duodenoileal transit, lipase, chymotrypsin, amylase, and trypsin lost 71 +/- 5, 63 +/- 5, 43 +/- 7, and 38 +/- 9% of activity, respectively (P < 0.01 vs. distal duodenum). During duodenojejunal transit, the activity of each enzyme decreased more than 35% (P < 0.01 vs. distal duodenum), and infusion of more calories into the duodenum improved survival of all enzymes except trypsin (P < 0.05). During jejunoileal transit, greater amounts and concentrations of calories and carbohydrate improved survival of only lipolytic activity (P < 0.01, P < 0.05, respectively), and loss of lipolytic activity correlated directly with delivery of bile acids (r = 0.56, P = 0.05) and chymotrypsin (r = 0.80, P = 0.001) to the distal jejunum. We conclude that intraluminal nutrients increase survival of enzyme activities in the proximal intestine. After absorption of nutrients, the action of chymotrypsin and bile acids decrease lipolytic activity more than activity of other enzymes.

Bacterial lipase and high-fat diets in canine exocrine pancreatic insufficiency: a new therapy of steatorrhea?

BACKGROUND & AIMS

Nutrients and properties of lipases affect survival of lipolytic activity during aboral gastrointestinal transit. Whether different doses and formulations of bacterial lipase and diets affect steatorrhea was tested in pancreatic-insufficient dogs.

METHODS

A dose of 0-600,000 IU of powdered and 135,000 and 300,000 IU of liquid bacterial lipase was given with a standard meal to 5 dogs with ligated pancreatic ducts. In 4 dogs, 0 or 300,000 IU (normal 6-hour postprandial amount) of powder bacterial lipase was also given with five meals containing 850 kcal with different nutrient caloric densities (mixture design). Coefficients of fat absorption during 72-hour fecal balance studies were used to assess treatments.

RESULTS

With the standard meal, powder bacterial lipase reduced steatorrhea in a dose-dependent manner (P = 0.03), and 135,000 and 300,000 IU of the liquid form decreased steatorrhea more than powder bacterial lipase (P = 0.017 and 0.057, respectively). Coefficients of fat absorption with 300,000 IU of powder bacterial lipase correlated (r2 = 0.79; P < 0.001) with increasing proportions of fat calories in diets.

CONCLUSIONS

Liquid bacterial lipase decreases steatorrhea more than powder, and 300,000 IU of powder bacterial lipase ingested with high-fat meals corrects canine pancreatic steatorrhea. The combination of adequate mixing of small amounts (milligrams) of bacterial lipase and high-fat meals abolishes canine steatorrhea and may abolish human pancreatic steatorrhea.

Hereditary pancreatitis and the risk of pancreatic cancer. International Hereditary Pancreatitis Study Group

BACKGROUND

Hereditary pancreatitis is an autosomal-dominant disease, with a variable expression and an estimated penetrance of 80%. The gene for this disease has recently been mapped to chromosome 7q35, and the defect is believed to be caused by a mutation in the cationic trypsinogen gene. Acute attacks of abdominal pain begin early in life and the disease often progresses to chronic pancreatitis. Although the risk of pancreatic cancer is thought to be increased in more common types of chronic pancreatitis, the frequency of pancreatic cancer in the inherited type of pancreatitis is uncertain.

PURPOSE

The aim of this study was to assess the frequency of pancreatic cancer and other tumors in patients with hereditary form of pancreatitis.

METHODS

To determine the natural history of hereditary pancreatitis, we invited all members of the American Pancreatic Association and the International Association of Pancreatology to participate in a longitudinal study of this rare form of pancreatitis. The initial criteria for patient eligibility were as follows: early age (< or = 30 years) at onset of symptoms, positive family history, and absence of other causes. From April 1995 through February 1996, 37 physicians from 10 countries contributed medical records of 246 (125 males and 121 females) patients thought to have hereditary pancreatitis as the most likely diagnosis. This group included 218 patients where the diagnosis appeared to be highly probable and 28 additional patients where the diagnosis of hereditary pancreatitis was less certain: 25 patients who had relatively late onset of disease and a positive family history and three patients with onset of disease before age 30 years but with an uncertain family history. We reviewed all causes of death and compared the observed to the expected frequency of cancer in this historical cohort of patients with hereditary pancreatitis. The strength of the association between pancreatitis and pancreatic cancer was estimated by the standardized incidence ratio (SIR), which is the ratio of observed pancreatic cancer cases in the cohort to the expected pancreatic cancers in the background population, adjusted for age, sex, and country.

RESULTS

The mean age (+/- standard deviation [SD]) at onset of symptoms of pancreatitis was 13.9 +/- 12.2 years. Compared with an expected number of 0.150, eight pancreatic adenocarcinomas developed (mean age +/- SD at diagnosis of pancreatic cancer: 56.9 +/- 11.2 years) during 8531 person-years of follow-up, yielding an SIR of 53 (95% confidence interval [CI] = 23-105). The frequency of other tumors was not increased: SIR = 0.7 (95% CI = 0.3-1.6). Eight of 20 reported deaths in the cohort were from pancreatic cancer. Thirty members of the cohort have already been tested for the defective hereditary pancreatitis gene: all 30 carry a mutated copy of the trypsinogen gene. The transmission pattern of hereditary pancreatitis was known for 168 of 238 patients without pancreatic cancer and six of eight with pancreatic cancer. Ninety-nine of the 238 patients without pancreatic cancer and six of the patients with pancreatic cancer inherited the disease through the paternal side of the family. The estimated cumulative risk of pancreatic cancer to age 70 years in patients with hereditary pancreatitis approaches 40%. For patients with a paternal inheritance pattern, the cumulative risk of pancreatic cancer is approximately 75%.

CONCLUSIONS

Patients with hereditary pancreatitis have a high risk of pancreatic cancer several decades after the initial onset of pancreatitis. A paternal inheritance pattern increases the probability of developing pancreatic cancer.

Role of extrinsic innervation in carbohydrate-induced ileal modulation of pancreatic secretion and upper gut function

Previously we showed that carbohydrate (CHO) in the ileum slowed gastric emptying and increased pancreatic amylase secretion relative to that of other enzymes. Our aim here was to determine if extrinsic innervation of the jejunoileum participates in the CHO-induced ileal modulation of postprandial upper gut function. Six dogs were studied before and 2-3 weeks after in situ neural isolation of the jejunoileum (complete extrinsic denervation). Gastric emptying (GE) and pancreatic amylase secretion were quantitated for 4 h after a 300-ml meal containing 3H-PEH (liquid marker) and 99mTc sulfur colloid cooked with eggs (solid marker). Coincident with feeding, we started a distal ileal infusion of 150 mM NaCl or 40 mg.min-1 CHO. Extrinsic denervation abolished the slowing of GE of liquids and solids and the augmented increase in amylase and trypsin in relation to solid emptying seen in the neurally intact dogs prior to denervation. Denervation also abolished the decrease in total pancreatic exocrine secretion in response to ileal CHO. Increases in plasma concentrations of peptide YY (PYY) were correlated temporally with decreased GE of solids and increased exocrine secretion during ileal CHO in neurally intact dogs, but no increases in PYY release occurred after extrinsic denervation. Extrinsic denervation of the jejunoileum abolished the effect of ileal CHO on GE of liquids and solids, the decrease in total amylase secretion during ileal CHO, and the relative increase in enzyme secretion expressed as total enzyme output per percentage solid marker emptied. Extrinsic innervation of the jejunoileum mediates ileal modulation of GE and the relationship of amylase secretion to GE of solids. The mechanism of this effect may be via neurally mediated release of PYY.

What is the best biochemical test to diagnose acute pancreatitis? A prospective clinical study

OBJECTIVE

To determine which biochemical test is best to distinguish acute pancreatitis from other pancreatic and nonpancreatic diseases associated with hyperamylasemia.

DESIGN

We conducted a prospective clinical study of 836 consecutive patients who had a total serum amylase test requested by a physician during a 7-month period.

MATERIAL AND METHODS

Radioimmunoassay and enzymatic activity methods were used to measure pancreas-specific proteins of varied size, charge, and stability. In addition, scoring systems were used for the diagnosis of pancreatitis, and statistical analyses were done to determine sensitivity and specificity.

RESULTS

We found minor differences in sensitivity and specificity for diagnosis of acute pancreatitis among pancreatic isoamylase, phospholipase A2, colipase, lipase, and carboxylester lipase. Of these tests, the combination of isoamylase and phospholipase A2 had a small but statistically significant increased sensitivity (90%; 95% confidence interval [CI] = 74 to 98%) and specificity (93%; 95% CI = 91 to 95%) over isoamylase (90% and 92%, respectively; 95% CI = 90 to 94%) and phospholipase A2 (90% and 75%, respectively; 95% CI = 72 to 78%) alone for the diagnosis of acute pancreatitis.

CONCLUSION

Pancreas-specific proteins are satisfactory for diagnosing acute pancreatitis if the test is validated by the laboratory. Clinically, the slight advantage of using both isoamylase and phospholipase A2 does not outweigh the expense of performing two assays; we recommend using isoamylase to diagnose acute pancreatitis.

Character of a wheat amylase inhibitor preparation and effects on fasting human pancreaticobiliary secretions and hormones

BACKGROUND & AIMS

Amylase inhibition induces carbohydrate tolerance, satiety, and weight loss and prolongs gastric emptying, effects that may be useful in the treatment of obesity and non-insulin-dependent diabetes mellitus. The aim of this study was to determine (1) purity of a wheat amylase inhibitor preparation, (2) intraduodenal concentration of the wheat amylase inhibitor preparation that inhibits > 90% amylase activity (which causes carbohydrate malabsorption), and (3) if the inhibitor alters pancreaticobiliary secretions or intraluminal pH.

METHODS

High-performance liquid chromatography followed by electrophoresis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis were used for characterization. Groups of 3 subjects received intraduodenal infusions of 3.0, 4.5, or 6.0 mg/mL of the inhibitor for 90 minutes during the middle of a 270-minute essential amino acid solution infusion (which stimulates 50% maximal pancreatic enzyme secretion). Pancreatic enzyme and bile acid delivery to the duodenum were measured for a 270-minute period.

RESULTS

The inhibitor is 96% protein, 59% containing 0.19, 0.28, 0.38, and 0.53 inhibitors. The 0.38 inhibitor has the most antipancreatic alpha-amylase activity. The inhibitor reduced amylase activity in the duodenum dose dependently (r = 0.7; P = 0.04); > 4 mg/mL inhibited > 90% amylase activity but did not affect delivery of other enzymes or bile acids to the duodenum or gastric or duodenal pH.

CONCLUSIONS

The preparation has a high protein purity and a high specific activity against alpha-amylase activity and effectively inhibits human pancreatic amylase activity secreted into the duodenum.