Inhibition of human exocrine pancreatic secretion by the long-acting somatostatin analogue octreotide (SMS 201-995)

An updated systematic review and meta-analysis of the use of octreotide for the prevention of postoperative complications after pancreatic resection

BACKGROUND

The use of octreotide prophylaxis following pancreatic surgery is controversial. We aimed to evaluate the effectiveness of octreotide for the prevention of postoperative complications after pancreatic surgery through this systematic review and meta-analysis.

METHODS

Literature databases (including the MEDLINE, EMBASE, and Cochrane databases) were searched systematically for relevant articles. Only randomized controlled trials (RCTs) were eligible for inclusion in our research. We extracted the basic information regarding the patients, intervention procedures, and all complications after pancreatic surgery and then performed the meta-analysis.

RESULTS

Thirteen RCTs involving 2006 patients were identified. There were no differences between the octreotide group and the placebo group with regard to pancreatic fistulas (PFs) (relative risk [RR] = 0.79, 95% confidence interval [CI] = 0.62-0.99, P = .05), clinically significant PFs (RR = 1.01, 95% CI = 0.68-1.50, P = .95), mortality (RR = 1.21, 95% CI = 0.78-1.88, P = .40), biliary leakage (RR 0.84, 95% CI = 0.39-1.82, P = .66), delayed gastric emptying (RR = 0.83, 95% CI = 0.54-1.27, P = .39), abdominal infection (RR = 1.00, 95% CI = 0.66-1.52, P = 1.00), bleeding (RR = 1.16, 95% CI = 0.78-1.72, P = .46), pulmonary complications (RR = 0.73, 95% CI = 0.45-1.18, P = .20), overall complications (RR = 0.80, 95% CI = 0.64-1.01, P = .06), and reoperation rates (RR = 1.18, 95% CI = 0.77-1.81, P = .45). In the high-risk group, octreotide was no more effective at reducing PF formation than placebo (RR = 0.81, 95% CI = 0.67-1.00, P = .05). In addition, octreotide had no influence on the incidence of PF (RR = 0.38, 95% CI = 0.14-1.05, P = .06) after distal pancreatic resection and local pancreatic resection.

CONCLUSION

The present best evidence suggests that prophylactic use of octreotide has no effect on reducing complications after pancreatic resection.

A Novel Method for Pain Relief in Chronic Pancreatitis: an Old Drug in a New Pack: a Controlled Study

Most of pain-relieving agents in chronic pancreatitis are nonspecific and unpredictable. Omeprazole induces hypergastrinemia due to reduced gastric acidity. Raised serum gastrin, in turn, modulates to reduce secretin level. Secretin is responsible for secretion of almost 80 % bicarbonate-rich pancreatic juice from the ductular epithelium without affecting enzyme output. It is a prospective randomized study in patients with CT-confirmed chronic pancreatitis. The control group got the standard care and 60 mg of omeprazole twice daily was added to the test group. Absence of pain relief at 14 days was considered as failure. Pain relief, weight gain and any toxic effect of omeprazole were reviewed at 12 months. One hundred thirty-seven cases were included, with an age range of 19 to 72 years. (mean 42.67). The majority of them were alcoholic males. At 2 weeks, pain relief was noted in 47/69(68.1 %) and 63/65(96.96 %) in the control and omeprazole group, respectively. At the end of 1 year, the omeprazole group had greater weight gain (95 %) than the control group (69.5 %). All the pseudocysts in the omeprazole group and most in the control group resolved. No side effect of omeprazole was seen. The high-dose omeprazole (HDO) group of patients had significantly better pain relief in chronic pancreatitis than those treated with conventional therapy. A high number of cases gained weight in the HDO group than the controlled group. No patient had clinical, endoscopic, biochemical, or haematological toxicity of HDO. More studies are necessary.

Serotonin hormonally regulates lacrimal gland secretory function via the serotonin type 3a receptor

Tears are extracellular fluid secreted from the lacrimal gland (LG). Tears consist of a dynamic tri-layered film composed of secretions from the LG, Meibomian gland, and conjunctival goblet cells. The LG secretes the aqueous component of the tear, the Meibomian gland secretes the lipid component, and conjunctival goblet cells secrete mucin. The regulation of LG activity via the autonomic nervous system has been recognized as fundamental to maintaining aqueous tear flow. Here, we describe the role of a hormone, peripheral serotonin, in tear secretion. We found that blood serotonin concentration, changed by feeding a diet deprived of the serotonin precursor tryptophan, correlated with tear secretion, and that a sustained decrease in serotonin resulted in LG atrophy and autophagy. The combination of a decrease in serotonin with the interruption of autonomic neural stimuli to the LG preceded these alterations. Furthermore, we found that the serotonin type 3a receptor expressed in LG acinar cells is involved in tear secretion via intracellular calcium mobilization. Our findings demonstrate that hormonal regulation by serotonin, in cooperation with the autonomic nervous system, regulates tear secretion.

Efficacy of the prophylactic use of octreotide for the prevention of complications after pancreatic resection: An updated systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The use of octreotide prophylaxis in the prevention of complications after pancreatic resection remains controversial. The aim of this systematic review and meta-analysis was to evaluate the efficacy of octreotide prophylactic treatment to prevent complications after pancreatic resection.

METHODS

Five databases (PubMed, Medline, SinoMed, Embase, and Cochrane Library) were searched for eligible studies from 1980 to November 2016 with the limitation of human subjects and randomized controlled trials (RCTs). Data were extracted independently and were analyzed using RevMan statistical software version 5.3 (Cochrane Collaboration, http://tech.cochrane.org/revman/download). Weighted mean differences (WMDs), risk ratios (RRs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration risk of bias tool was used to assess the risk of bias.

RESULTS

Twelve RCTs comprising 1902 patients were identified as eligible. The methodological quality of the trials ranged from low to moderate. A pooled analysis of effectiveness based on the data from each study revealed that octreotide could significantly reduce the rate of pancreatic fistula (PF) after pancreatic resection (RR = 0.75, 95% CI = 0.57-0.98, P = .04). The same findings were discovered in multicenter and European subgroups with a subgroup analysis; no obvious differences were noted in American, Asian, and single-center subgroup analyses. An equal effect was observed between the use or non-use of octreotide groups regarding mortality (RR = 1.24, 95% CI = 0.77-2.02, P = .38). Octreotide had no advantages in regards to mortality improvement. The total numbers of complications associated with the use or non-use of octreotide were similar (RR = 0.77, 95% CI = 0.58-1.03, P = .08). Among the high-risk group, octreotide was more effective in reducing complications (RR = 0.61, 95% CI = 0.46-0.82, P = .0009). Compared with the patients who did not receive prophylactic treatment, the patients who underwent pancreatic resection benefited from octreotide because it had better efficacy in preventing fluid collection and postoperative pancreatitis.

CONCLUSION

The prophylactic use of octreotide is suitable for preventing postoperative complications, especially PF and fluid collection as well as postoperative pancreatitis. However, no obvious differences were noted regarding mortality. In view of the clinical heterogeneity and varying definitions of PF, whether these conclusions are broadly applicable should be further determined in future studies.

Dumping syndrome after esophageal, gastric or bariatric surgery: pathophysiology, diagnosis, and management

BACKGROUND

Dumping syndrome, a common complication of esophageal, gastric or bariatric surgery, includes early and late dumping symptoms. Early dumping occurs within 1 h after eating, when rapid emptying of food into the small intestine triggers rapid fluid shifts into the intestinal lumen and release of gastrointestinal hormones, resulting in gastrointestinal and vasomotor symptoms. Late dumping occurs 1-3 h after carbohydrate ingestion, caused by an incretin-driven hyperinsulinemic response resulting in hypoglycemia. Clinical recommendations are needed for the diagnosis and management of dumping syndrome.

METHODS

A systematic literature review was performed through February 2016. Evidence-based medicine was used to develop diagnostic and management strategies for dumping syndrome.

RESULTS

Dumping syndrome should be suspected based on concurrent presentation of multiple suggestive symptoms after upper abdominal surgery. Suspected dumping syndrome can be confirmed using symptom-based questionnaires, glycemia measurements and oral glucose tolerance tests. First-line management of dumping syndrome involves dietary modification, as well as acarbose treatment for persistent hypoglycemia. If these approaches are unsuccessful, somatostatin analogues should be considered in patients with dumping syndrome and impaired quality of life. Surgical re-intervention or continuous enteral feeding may be necessary for treatment-refractory dumping syndrome, but outcomes are variable.

CONCLUSIONS

Implementation of these diagnostic and treatment recommendations may improve dumping syndrome management.

Pathophysiology, diagnosis and management of postoperative dumping syndrome

Dumping syndrome is a frequent complication of esophageal, gastric or bariatric surgery. Rapid gastric emptying, with the delivery to the small intestine of a significant proportion of solid food as large particles that are difficult to digest, is a key event in the pathogenesis of this syndrome. This occurrence causes a shift of fluid from the intravascular component to the intestinal lumen, which results in cardiovascular symptoms, release of several gastrointestinal and pancreatic hormones and late postprandial hypoglycemia. Early dumping symptoms comprise both gastrointestinal and vasomotor symptoms. Late dumping symptoms are the result of reactive hypoglycemia. Besides the assessment of clinical alertness and endoscopic or radiological imaging, a modified oral glucose tolerance test might help to establish a diagnosis. The first step in treating dumping syndrome is the introduction of dietary measures. Acarbose can be added to these measures for patients with hypoglycemia, whereas several studies advocate guar gum or pectin to slow gastric emptying. Somatostatin analogs are the most effective medical therapy for dumping syndrome, and a slow-release preparation is the treatment of choice. In patients with treatment-refractory dumping syndrome, surgical reintervention or continuous enteral feeding can be considered, but the outcomes of such approaches are variable.

Efficacy of the long-acting repeatable formulation of the somatostatin analogue octreotide in postoperative dumping

BACKGROUND & AIMS

Several studies have established symptomatic and mechanistic benefits of the somatostatin analogue octreotide in patients with dumping syndrome, but clinical use is hampered by the requirement for subcutaneous administration 3 times daily. We compared the efficacy of subcutaneous octreotide with that of the long-acting repeatable (LAR) octreotide formulation, which is administered monthly, in patients with dumping syndrome.

METHODS

The study included 30 consecutive patients with postoperative dumping, evidenced by oral glucose tolerance test (OGTT) results and insufficient response to dietary measures. OGTT, dumping severity score (summary of scores 0-3 for 8 early and 6 late dumping symptoms), and quality-of-life data were evaluated at baseline, after 3 days of subcutaneous administration of octreotide (0.5 mg), and then after 3 monthly intramuscular injections of octreotide LAR (20 mg).

RESULTS

Both formulations of octreotide significantly reduced total dumping severity scores (21.7 +/- 1.6 at baseline, 11.2 +/- 1.2 for subcutaneous and 14.0 +/- 1.8 for LAR formulations; P < .05). This reduction was associated with significant improvements in the increase in pulse rate (13.8 +/- 5.8 at baseline vs -0.3 +/- 2.2 and 1.9 +/- 1.7; P < .05) as well as the increase in hematocrit level (4.0 +/- 1.4 at baseline vs 0.3 +/- 0.9. and 0.4 +/- 1.0; P < .05), and the lowest glycemia level in the OGTT (54.1 +/- 6.7 at baseline vs 98.9 +/- 7.1 and 67.8 +/- 5.9; P < .05). LAR octreotide administration significantly improved patients' quality of life. Patients' evaluations of their overall treatment efficacy was higher on LAR compared with the subcutaneous formulation (83% vs 52%; P = .01). Gallbladder stones occurred in 4 patients.

CONCLUSIONS

Monthly administration of LAR octreotide improves OGTT results, symptoms, and quality of life in patients with postoperative dumping.

Post-ERCP pancreatitis and its prevention

Pancreatitis remains the most common severe complication of endoscopic retrograde cholangiopancreatography (ERCP), and typically develops in 5-7% of patients. Although most post-ERCP pancreatitis (PEP) is mild, severe pancreatitis and its complications (including a systemic inflammatory response or the development of pseudocysts or pancreatic necrosis) can occur, and in rare cases death can result. A means of preventing PEP in all patients who undergo the procedure remains elusive. Proper patient selection for ERCP is critical to avoid unnecessary risk. Pharmacologic attempts to prevent PEP have been largely unsuccessful; encouraging results have been difficult to validate. Prophylactic stenting of the pancreatic duct and minimally traumatic cannulation techniques offer the most promise as a means of preventing PEP. This manuscript reviews risk factors for PEP as well as pharmacologic and procedural means that can be used to reduce its incidence.

Octreotide therapy for advanced hepatocellular carcinoma

Treatment options for advanced hepatocellular carcinoma (HCC) remain limited. Recently, octreotide has been proposed for therapy, although its efficacy remains controversial. Thus, the aim of this open-label pilot study was to evaluate the response of HCC to long-acting octreotide (Sandostatin LAR). Thirty patients were enrolled for this prospective 2-year trial. Initially, patients were given short acting octreotide to ensure drug tolerability. Thereafter, patients received long-acting octreotide 30 mg IM every 4 to 6 weeks. Measurable disease was assessed at 3-month intervals. Five of 30 patients were unable to tolerate the test dose, and 1 patient was reevaluated and underwent hepatic resection. The remaining 24 patients, who received long-acting octreotide, all had advanced stage of disease with multifocal-massive morphology (67%), vascular thrombosis (63%), or extrahepatic spread (17%), but well compensated liver disease. The treatment was well tolerated, except for diarrhea. Median time to tumor progression was 3.6 months, and median survival was 5.1 months. Seven patients (29%) had stable disease (median duration of 8.0 months) with 2 patients demonstrating disease stability for 24 months. In conclusion, although occasional patients appear to have stable disease on long-acting octreotide therapy, overall the beneficial response in terms of time to tumor progression and survival is limited.

Adaptation of the human pancreas to inhibition of luminal proteolytic activity

BACKGROUND & AIMS

Feedback regulation of pancreatic enzyme secretion is well established in animals, and their pancreases are able to adapt to intraduodenal inhibition of pancreatic enzymes by proteinase inhibitors such as Camostate (FOY-305; Schwarz GmbH, Monheim, Germany). In this study, we addressed whether similar adaptive changes occur in the human pancreas after 4 weeks of 2 g/day Camostate application.

METHODS

Before, at the end of, and 2 weeks after 4-week Camostate treatment (four times 500 mg daily), pancreatic changes were analyzed with the use of a secretin-cerulein test, a test-meal stimulation, cholecystokinin plasma measurement, and standardized ultrasonographic investigations of the pancreas.

RESULTS

Duodenal trypsin output after secretion stimulation was significantly increased (+44%; P < 0.01) and duodenal bicarbonate output decreased 22% (P < 0.05) after 4 weeks of Camostate application. The size of the pancreatic head (vertical) increased 8% (P < 0.05) at week 4 and decreased to pretreatment values 2 weeks after treatment (week 6). The other three diameters measured (head oblique, body, and tail) showed a similar pattern. Stimulated cholecystokinin plasma levels 15 minutes after application of a standard test meal increased 62% (P < 0.05).

CONCLUSIONS

The human pancreas adapts to oral application of the proteinase inhibitor Camostate. These findings support the theory that feedback control of the exocrine pancreas operates in humans.

Influence of high-dose pancreatic enzyme treatment on pancreatic function in healthy volunteers

CONCLUSIONS

Adaptive changes in exocrine and endocrine pancreatic function, as well as changes in pancreas size and morphology, were not observed after 4-wk of oral pancreatic enzyme application. These findings suggest that the normal pancreas does not significantly adapt--either morphologically or functionally--to a 4-wk oral application of high-dose pancreatic enzymes.

BACKGROUND

The control of exocrine pancreatic enzyme secretion is not completely understood. Although it has been established that exocrine pancreatic secretion is mainly regulated in the short-term by the amount of pancreatic enzymes in the proximal small intestine, it is not known whether long-term application of pancreatic enzymes causes changes in exocrine pancreatic secretion in humans.

METHODS

Twelve healthy male volunteers (median age 27 yr) participated in a prospective, randomized, placebo-controlled, double-blind study. Six were placed in the treatment group and six in the placebo group. Over a 4-wk period, the six subjects in the treatment group took 18 capsules of Panzytrat (20,000 units of lipase, 18,000 units of amylase, and 1000 units of protease per capsule) daily. Before (wk 0), 4 wk following pancreatic enzyme application and 2 wk afterward, a secretin-cerulein test was carried out in all subjects to study exocrine pancreatic function (trypsin, chymotrypsin, bicarbonate content, and total pancreatic fluid secretion in the duodenum). One day following the secretin-cerulein test, a standard test meal was given to all subjects to analyze endocrine pancreatic function. Additionally, before starting the treatment, once per week during treatment and 2 wk afterward, an ultrasound examination of the pancreas was carried out to see whether there was any change in pancreas size and morphology.

RESULTS

Trypsin content in the duodenal aspirates following simultaneous stimulation with secretin and cerulein after 4 wk of high-dose pancreatic enzyme application was 92% in the treatment group and 82% in the placebo group compared with the wk 0 test results (100%). Two weeks after enzyme application, the secretin/cerulein-stimulated trypsin content was 88% in the treatment group and 107% in the placebo group. None of these changes was statistically significant. The same results were seen for chymotrypsin content, amylase, and bicarbonate content as well as for total pancreatic fluid secretion. Additionally, no change in the endocrine pancreatic function could be observed after 4 wk of pancreatic enzyme treatment. Pancreas ultrasonography revealed no alteration in pancreas size or parenchymal structure during the 4 wk of treatment and the following 2 wk.

Randomized controlled multicentre study of the prevention of complications by octreotide in patients undergoing surgery for chronic pancreatitis

A randomized double-blind placebo-controlled multicentre trial was carried out in 247 patients undergoing major elective surgery for chronic pancreatitis to clarify whether the perioperative application of octreotide prevents postoperative complications. Eleven complications were defined, including death, anastomotic leakage, pancreatic fistula, abscess, fluid collection, shock, sepsis, bleeding, pulmonary insufficiency, renal insufficiency and postoperative pancreatitis. A total of 124 patients underwent pancreatic head resection, 55 left resection, 61 pancreaticojejunostomy and seven had other procedures. The overall mortality rate was 1.2 per cent (octreotide group 1.6 per cent, placebo group 0.8 per cent [corrected] (P not significant)). The postoperative complication rate in the octreotide group was 16.4 per cent (20 of 122 patients) and in the placebo group 29.6 per cent (37 of 125) (P < 0.007). The perioperative application of octreotide substantially reduces the risk of postoperative complications in patients undergoing major pancreatic surgery for chronic pancreatitis.

Efficacy of octreotide in the prevention of complications of elective pancreatic surgery. Italian Study Group

A placebo-controlled double-blind multicentre study, with randomization into parallel groups, was performed to determine whether perioperative subcutaneous administration of octreotide 0.1 mg every 8 h reduces the rate of complications specifically related to pancreatic surgery. In all, 252 patients were evaluated (153 men, 99 women; mean(s.e.m.) age 53.1(0.8) years) who had pancreatic or periampullary tumour or other duodenal disease (157 patients) or chronic pancreatitis (95) and were undergoing elective pancreatic resection (100 Whipple's procedure, 60 distal resection, 12 others), pancreaticojejunostomy (66) or enucleation of pancreatic lesions (14). The proportion of patients with complications was significantly lower in the group treated with octreotide than in the placebo group (15.6 versus 29.2 per cent, P = 0.01). Octreotide thus appears to reduce substantially the risk of complications related to elective pancreatic surgery. Moreover, treatment acceptability was high.