The Role of Genetics in Sporadic GEP-NETs: A Comprehensive Review of the Literature

Neuroendocrine tumors (NETs) are composed of a heterogeneous group of malignancies from neuroendocrine cell compartments, with roles in both the endocrine and the nervous system. The majority of NETs are gastroenteropancreatic (GEP) in origin, arising in the foregut, midgut, or hindgut. The genomic landscape of GEP-NETs has been scarcely studied in terms of genomic profiling.The following algorithm was followed using the keywords neuroendocrine, genomics, targeted therapy, personalized medicine, gastroenteropancreatic and NET. The search was performed in PubMed and ScienceDirect database. Our current knowledge of sporadic GEP-NETs genetics must be further advanced to elucidate the molecular basis and pathogenesis of the disease, improve the accuracy of diagnosis, and guide tailor-made therapies.

Results of a prospective multicenter neuroendocrine tumor registry reporting on clinicopathologic characteristics of Greek patients

BACKGROUND

The rare incidence of neuroendocrine neoplasms (NENs) has contributed to a paucity of large epidemiologic studies of patients with this condition. We investigated the occurrence and clinicopathologic features of NENs in Greece.

METHODS

Between October 2010 and November 2012 we collected data on 246 newly diagnosed patients from a broad-based multi-institutional registry that comprises eight academic and hospital sites in Greece. The WHO 2010 pathologic classification and the 7th AJCC Staging system was applied in all cases.

RESULTS

Of all patients 94 % had a sporadic and 6 % a multiple endocrine neoplasia tumor; 63.4 % were gastroenteropancreatic-(GEP)-NENs, 17.9 % Head & Neck NENs, 9.8 % NENs of Unknown Primary, 6.5 % Lung NENs and 2.4 % Pheochromocytomas. Gastric and pancreatic NENs were the most common primary sites. Poorly differentiated neuroendocrine carcinomas (NEC) were 9.3 %, all sporadic. Fifteen percent of patients were asymptomatic at presentation, 24 % had a first symptom of the disease related to endocrine syndrome and 61 % had symptoms related to locally advanced or metastatic disease. Metastatic disease was established in 25 % of tumors most frequently in the GEP NEN group. Findings are presented according to Ki-67 distribution. MRI had a higher diagnostic positive yield than Octreoscan. Somatostatin analogs, lanreotide and octreotide acetate, were prescribed at 38.5 & 61.5 % of NEN patients respectively and were found to be equally effective at providing symptomatic relief.

CONCLUSIONS

This is to our knowledge the first study of a Greek tumor registry and one of the few European Registries providing information regarding clinicopathologic characteristics and therapies in patients with neuroendocrine tumors of various origin sites, beyond GEP NENs.

Carcinoid tumors of the duodenum and the ampulla of Vater: current diagnostic and therapeutic approach in a series of 8 patients. Case series

AIM

To describe the specific characteristics of duodenal/perivaterian carcinoids and to analyze the diagnostic/therapeutic approach.

MATERIAL AND METHODS

Eight patients were included in our study. Symptoms on admission included dyspepsia, upper gastrointestinal (GI) bleeding and anemia. All patients underwent upper GI endoscopy and gastrointestinal peptides (gastrin) and neuroendocrine markers (Chromogranin-A, CgA) measurement. Imaging studies were performed in all patients, including OCTREOSCAN, while in patients with ACs MRCP or ERCP was also performed, when necessary. Definite diagnosis was confirmed by histopathologic examination.

RESULTS

Polypoid masses (carcinoids) were revealed at duodenal bulb and ampulla of Vater, in 5 and 3 patients, respectively. Serum gastrin was moderately increased in 4 patients, while in one patient it was more than 1000 pg/ml. Serum CgA was moderately increased in one patient, in whom OCTREOSCAN detected a solitary hepatic metastasis. Two patients with DC, of less than 1 cm of diameter, were treated by endoscopic polypectomy, while all the other patients underwent surgery. The patient with hepatic metastasis and positive OCTREOSCAN received also Octreotide LAR, resulting in stabilization of disease. No recurrence or metastases were observed during follow-up (range : 1.5-9.6 years).

CONCLUSIONS

In DC tumors <1 cm endoscopic excision with close follow-up is an adequate treatment, while in tumors >1 cm and in AC, surgical resection is the treatment of choice. In metastatic tumors, resection of the primary lesion with administration of somatostatin analogues may stabilize the disease and improve patient's quality of life.

Chromogranin a levels in diagnosis, treatment and follow-up of 42 patients with non-functioning pancreatic endocrine tumours

BACKGROUND/AIMS

Non-functioning pancreatic endocrine tumours (NFPET) constitute the largest component (35-50%) of pancreatic endocrine tumours. They are characterized by the absence of symptoms of hormone hypersecretion and frequently have clinical manifestations similar to the more common exocrine pancreatic adenocarcinoma. The present studyaims toevaluate the clinical features, diagnostic approach and, in particular, the significance of serum chromogranin A levels (CgA) in the management and outcome of 42 patients with NFPET (from a series of 121 patients with pancreatic endocrine tumours).

METHODS

Twenty-five males and 17 females were included, and the mean age at diagnosis was 52.3 years (range: 26-68 years). The diagnosis for each patient was established by histopathological examination and immunohistochemistry. After the histopathological confirmation of diagnosis and during the follow-up period, patients were evaluated clinically and radiologically (including OctreoScan), whilst fasting gut hormones (including CgA) were also estimated. At diagnosis, all patients were checked for the presence of multiple endocrine neoplasia type I syndrome. The follow-up was complete and ranged from 12 to 86 months (mean: 49 months).

RESULTS

Dyspepsia (66.5%) and weight loss (47.6%) were the most common symptoms at diagnosis, while in 21.4% of patients tumour lesions were revealed incidentally. Plasma CgA levels were significantly or moderately elevated in all patients with liver metastases at diagnosis (64.3%). The levels also reflected tumour progression or response to treatment during the follow-up period. OctreoScan showed avid uptake in 77.8% of patients with hepatic metastases. Moreover, in 2 patients OctreoScan revealed unexpected metastatic mesenteric deposits, which had not been found by the other studies. However, it was negative in 6 patients with liver metastases, in whom tumours were proved to be poorly differentiated (high-grade).

CONCLUSIONS

(1) NFPET may present with clinical manifestations similar to those of an exocrine pancreatic tumour; (2) plasma CgA levels reflect tumour load, and also seem to correlate with tumour progression or response to treatment; (3) surgeryin patients with localized disease at presentation can be curative, while it can also reduce tumour burden in patients with metastases; (4) long-acting somatostatin analogues provide good quality of life and temporary disease stabilization in patients with low-grade tumours; (5) systemic chemotherapy or chemoembolization seem to be beneficial in high-grade and progressive tumours.

Treatment of small intestinal disease in systemic sclerosis with octreotide: a prospective study in seven patients

BACKGROUND

Symptoms associated with small intestinal involvement in patients with systemic sclerosis (SSc) are usually severe and resistant to treatment.

OBJECTIVES

To assess the safety and efficacy of octreotide in refractory small intestinal disease complicating SSc.

METHODS

Seven female patients (aged from 37 to 64 years old) with SSc were included in the study. All of them had symptoms compatible with small bowel pathology, nonresponding to several prokinetic agents. The patients received either subcutaneous octreotide, 0.1 mg twice daily, or intramuscular octreotide LAR (long-acting-release), 20 mg/mo. Symptom severity was assessed at baseline and at various follow-up points in a scale of 0-3, for each symptom. Significant gastrointestinal pathology was excluded by gastroscopy, colonoscopy, and small bowel enemas before octreotide administration.

RESULTS

All patients responded to octreotide, and a significant reduction from symptom severity at baseline (mean +/- SD: 2.9 +/- 1.1) was noted even in the first following month (1.3 +/- 0.5, P = 0.0006). A significant disturbance of defecation in 2 patients improved dramatically. Short relapses were noticed in patients who were initially treated with subcutaneous octreotide. These patients were subsequently treated with octreotide LAR, resulting in an overall symptom reduction at 6 months (0.7 +/- 0.5, P = 0.003), which was sustained during follow-up (median follow-up: 14.4 months). No side effects were noted.

CONCLUSION

These results suggest that long-term treatment with octreotide LAR may be a safe and effective approach for treatment of small intestinal disease in patients with SSc.

Gastrinomas associated with MEN-1 syndrome: new insights for the diagnosis and management in a series of 11 patients

BACKGROUND/AIMS

Approximately, 25-30% of patients (pts) have gastrinomas, (Zollinger-Ellison syndrome, ZES), as part of the inherited syndrome, multiple endocrine neoplasia 1 (MEN-1). The identification of MEN-1 syndrome in these pts is always important, as there are some differences in their management and prognosis. Among 33 pts with ZES, we present in this study 11 pts with ZES and MEN-1 syndrome, describing our diagnostic and therapeutic approach.

METHODOLOGY

Eleven pts with ZES and MEN-1 syndrome (6 females and 5 males) were included (mean age 51.8 years). The diagnosis of ZES was based upon: a) clinical features and b) high serum gastrin levels, while in 7/11 pts diagnosis was confirmed histopathologically. A variety of other gastrointestinal peptides, as well as the general neuroendocrine tumor marker, Chromogranin-A (CgA) were also estimated. All pts underwent conventional imaging methods (CT, MRI) and OCTREOSCAN or EUS when necessary, in order to localize the primary lesion or the metastases. The diagnosis of MEN-1 was based upon the presence of the other two MEN-1 related endocrinopathies (hyperparathyroidism, pituitary adenomas), revealed by estimation of several hormones (PTH, Prolactin, ACTH etc.) and performance of imaging studies of the pituitary and parathyroid glands. When MEN-1 syndrome was established, a familiar screening of pts was also performed, when possible. The mean duration of pts' follow-up was 6.1 years (range: 2.1-8.5 years).

RESULTS

At the time of presentation, 91% pts, had symptoms of peptic ulcer disease, refractory to treatment, while a history of colicky abdominal pain due to nephrolithiasis was also reported by 45% pts. Four of our pts had a blood relation. Serum gastrin levels at the time of diagnosis were greater than 1000pg/mL in 63.5% pts, while at the same time serum CgA levels were greater than 10 times the upper normal limit (<98ng/mL) in all pts. OCTREOSCAN and EUS revealed the primary tumor (in duodenum or pancreas) in 64% pts, in whom conventional methods showed no abnormalities at the same time. Parathyroid adenomas, pituitary adenomas and bronchial carcinoids were revealed in 11, 3 and 1 pts respectively, which were treated surgically. Also, surgical treatment of pancreatic or duodenal gastrinomas was performed in 54.5% pts, while pts who already had metastases (45%), or developed them during the follow-up period (18%), were treated by somatostatin analogues (63.6%) and chemotherapy (27.3%). Ten out of 11 pts are alive and in a good condition, whereas 1 patient died 2.8 years after diagnosis. Familiar screening revealed parathyroid adenomas in 4 children of our pts, which were treated surgically.

CONCLUSIONS

MEN-1 syndrome should always be considered in pts with ZES. A precise preoperative localization of all pancreaticoduodenal lesions, in combination with a surgical exploration and management by experienced surgeons, seems to be curative in pts without distal metastases. Non-surgical treatment with somatostatin analogues and chemotherapy in pts with progressive disease seem to stabilize the disease, although further studies are needed. A close clinical and biochemical follow-up of all pts, as well as their family members, is necessary in order to reveal and treat all MEN-1 related endocrinopathies and especially PETs, in an early stage.

Multimodality Treatment of Neuroendocrine Tumors of the Thymus

BACKGROUND

Neuroendocrine tumors of the thymus are rare neoplasms. Four patients with this tumor who underwent multimodality treatment are presented and the literature is briefly reviewed.

METHODS

The medical records of all patients treated for neuroendocrine tumors of the thymus from 1979 to 2002 were reviewed. Tumors were classified using a slight modification of the World Health Organization criteria.

RESULTS

The patients' median age was 38 years. All patients underwent extensive excision of the tumor. Histological diagnosis was atypical carcinoid (2), typical carcinoid (1), and small cell carcinoma (1). All patients developed recurrence(s). One patient died 132 months after diagnosis. The remaining three patients are alive with no symptoms at 135, 99, and 35 months, respectively, after diagnosis. Two patients with recurrences have been on treatment with Octreotide LAR with satisfactory results. One patient is free of disease.

CONCLUSIONS

Neuroendocrine tumors of the thymus are potentially aggressive tumors. Radical resection is the treatment of choice. The encouraging results obtained by administration of Octreotide LAR in two of our patients warrant further investigation.

VIPomas: an update in diagnosis and management in a series of 11 patients

BACKGROUND/AIMS

VIPoma is a rare pancreatic endocrine tumor (PET) which secretes excessive amounts of VIP (Vasoactive Intestinal Peptide) that causes a special clinical syndrome characterized by secretory diarrhea, hypokalemia and achlorhydria. Among a total number of 76 patients (pts) with PETs, we present in this study 11 pts with VIPoma syndrome focusing on our diagnostic and therapeutic approach, in parallel with a brief review of the literature.

METHODOLOGY

Eleven pts (7 males and 4 females), aged from 2 to 83 years (mean age 53.1 years) were included. The diagnosis was based upon compatible clinical features and serum VIP values and was supported by the estimation of other peptides and neuroendocrine markers such as gastrin, pancreatic polypeptide and chromogranin-A (CgA). In 10/11 pts, diagnosis was confirmed histopathologically. The primary or metastatic lesions were located by conventional imaging methods or by OCTREOSCAN or Endoscopic Ultrasound (EUS). The follow-up period ranged from 2.5-13.5 years (mean 4.8 years).

RESULTS

Chronic secretory diarrhea, which persisted despite fasting, was the main symptom in all pts of our study. VIP levels at the time of diagnosis were more than 3 or 10 times the upper normal limit in 7/11 (63.6%) or 4/11 (36.4%) pts, respectively. The primary lesion was detected by CT scan or MRI in 6/11 (54.5%), with EUS or abdominal angiography in 4/11 (36.4%). OCTREOSCAN revealed a solitary lesion in the right hepatic lobe, not detected by all the previous studies, while it detected, as a whole, the primary lesion in 10/11 (91%), and the metastases in 3/4 (75%) pts. In 7/11 (63.6%) the primary lesion was located in the pancreas, whereas in the rest it was in the duodenum or retroperitoneum. A surgical resection was possible in 7/11 (63.6%) pts, while pts with metastatic disease already or poorly differentiated tumors also received additional treatment with somatostatin analogues and chemotherapy. Liver metastases and poor differentiation of tumors seemed to be negative prognostic factors.

CONCLUSIONS

Clinical suspicion, early diagnosis and precise management may affect survival and improve the quality of life of patients. Also, surgical treatment, as extensive as possible, in combination with somatostatin analogues or chemotherapy when necessary, may also result in prolonged survival, also in patients with advanced disease.

Current diagnosis and treatment of gastrointestinal carcinoids in a series of 101 patients: the significance of serum chromogranin-A, somatostatin receptor scintigraphy and somatostatin analogues

BACKGROUND/AIMS

Carcinoids are relatively rare tumors that arise from neuroendocrine cells and have proved to be slow growing malignancies which involve many organs and most frequently the gastrointestinal (GI) tract. Herein we present in this study 101 pts with carcinoid tumors that originated from the GI tract and pancreas. Also, we analyze the clinical and pathological features, pointing out the characteristics of this group of neoplasms and describing our diagnostic and therapeutical approach, in parallel with a brief review of the literature.

METHODOLOGY

One hundred and one (66 females and 35 males, aged from 16 to 79 years) pts were included in our study. The primary tumors originated from the GI tract in 97/101 pts (appendix 34%, small intestine 31%, stomach 14%, duodenum 6%, colon 6%, rectum 3%) and from the pancreas in 4/101 (4%). The diagnosis was confirmed histologically in all cases, after surgical excision of the primary tumor or by biopsies taken during endoscopy. All pts were evaluated several times per year with clinical, biochemical and imaging assessments, including neuroendocrine markers [urinary 5-Hydroxyindoleacetic acid (5-HIAA), serum Chromogranin-A (CgA)] and Somatostatin Receptor Scintigraphy (OCTREOSCAN). The follow-up period ranged between 1.5 to 12.5 years (mean time: 5 years and 3 months) and it is still in progress.

RESULTS

Patients were referred to us with gastrointestinal symptoms or symptoms of the "carcinoid syndrome" (flushing, and diarrhea), depending mainly on the location of the primary tumors and the existence or not of metastases. CgA and 5-HIAA levels were increased especially in metastatic tumors. Localization of the primary tumors to facilitate surgery was made by many imaging techniques (US, CT, MRI, Enteroclysis, OCTREOSCAN) and endoscopic procedures. OCTREOSCAN was positive in 94% pts with metastatic disease. Furthermore, it revealed the primary and the metastatic lesions in 16% and 33% of pts with carcinoids of the small intestine respectively, while other conventional imaging procedures (including MRI) were negative at the same time. Seventy-four percent of the pts underwent a surgical resection of the primary tumor, while in 21%, an endoscopic polypectomy was performed. All pts with metastatic tumors and positive OCTREOSCAN, were treated with Somatostatin analogues, which resulted in control of symptoms (75%), stabilization of tumor growth (71%) or tumor shrinkage (9%). A combined therapy with the addition of interferon-a was initiated in pts in whom, despite the increase of drug dosage and the shortening of administration intervals, a complete clinical and biochemical response was no more achieved with Somatostatin analogues alone. Pancreatic carcinoids and also those that originated from the proximal colon were found to have worst prognosis.

CONCLUSIONS

a) Tumor size (especially in appendiceal and gastric carcinoids) and, also, the dispersion of disease, highly predict the evolution of the patients; b) serum Chromogranin-A seems to be a very useful tumor marker for the diagnosis and follow-up of pts with GI carcinoids; c) the introduction of new imaging techniques and especially OCTREOSCAN contributes to a better localization of the primary tumors and their metastases, as well as, to the right decision of the appropriate medical treatment; d) surgical excision is the treatment of choice in nonmetastatic tumors; and e) in pts with metastatic disease, the administration of Somatostatin analogues improves their quality of life.

Carcinoid tumors of the appendix. Prognostic factors and evaluation of indications for right hemicolectomy

BACKGROUND/AIMS

Carcinoid tumors of the appendix are thought to be the most common type of appendiceal neoplasms. Although the vast majority of appendiceal carcinoids behave in a benign fashion, they are considered malignant because they all have the potential for invasion, metastasis and production of physiologically active substances. The aim of our study is to evaluate the gravity of the prognostic factors and the indications for extended surgical treatment.

METHODOLOGY

Twenty-four patients, six male (aged from 18 to 59 years) and eighteen female (aged from 16 to 27 years) are included in our study. All these patients were managed and followed-up in our section during the last 17 years (follow-up range 10-17 years). Following confirmation of the diagnosis, secretion of 5-HLAA (5-Hydroxy-Inndole-Acetic Acid) was measured after a 24-hour collection of urine. Moreover, ultrasound (US) examination of the liver and computerized tomography (CT) scanning of the upper abdomen were performed after the operation in all patients. Also, patients with tumor size more than 1cm underwent a Somatostatin Receptor Scintigraphy (Octreoscan). The follow-up data of all patients included measurement of 5-HLAA and US examination every six months.

RESULTS

The most common site for the tumors was the tip of the appendix (18/22). In the rest of the cases, the neoplasms were located in the base (4/22) and in the body (2/22), while in one patient the mesoappendix was invaded. In sixteen patients the tumor size was less than 1cm, in seven patients the tumor diameter was measured to be 1 to 2cm and in one patient the tumor was 3cm. Most of our patients (16/22) underwent only an appendicectomy, while in the rest of them (in the patients with tumor size between 1-2cm and in the patient with invasion of mesoappendix) a right hemicolectomy was performed. No patient was found to have metastatic disease during the operation, while the patient with invasion of the mesoappendix developed metastases in the lung, two years after the operation.

CONCLUSIONS

Carcinoid tumors of the appendix, in most cases, are found incidentally during appendicectomies, especially in young females and usually are less than 1cm in size, which is probably the reason of the absence of metastases in all cases. Histological examination and size of the tumor are important factors that contribute to the selection of the surgical treatment and both must be estimated by the surgeons to make the final choice.

Alterations of systemic endotoxemia over the course of acute edematous pancreatitis. correlation to the advent of an infection?

BACKGROUND/AIMS

To define whether bacterial translocation occurs over the course of acute edematous pancreatitis and to correlate its presence to the advent of an infection since data in humans are lacking.

METHODS

Thirty-three patients hospitalized over the period January 2000-January 2001 were subjected to venipuncture at regular time intervals for the collection of blood samples for blood culture and for determination of endotoxins and of C-reactive protein. Endotoxins were measured by the Limulus assay and C-reactive protein by nephelometry.

RESULTS

A wide range of concentrations of endotoxins was observed over the first 3 days of the disease. Mean (+/-SE) of endotoxins was 4.01 +/- 1.36 and 2.42 +/- 0.95 EU/ml 3 and 6 h, respectively, after admission of afebrile patients. Respective values 3 and 6 h after admission of febrile patients were 3.03 +/- 1.14 and 5.84 +/- 2.28 EU/ml (normal <0.1 EU/ml); these values gradually decreased after the second day. No correlation was found between endotoxins and C-reactive protein. Endotoxins were increased as a result of the occurrence of an infection on the third day.

CONCLUSIONS

A significant level of endotoxemia is observed over the course of acute edematous pancreatitis, which might be correlated to the advent of the systemic inflammatory response.

Effect of octreotide administration on serum interleukin-6 (IL-6) levels of patients with acute edematous pancreatitis

BACKGROUND/AIMS

Based on former studies in experimental animals on the effect of octreotide on serum and ascitic levels of tumor necrosis factor-alpha and interleukin-6 in the field of necrotizing pancreatitis, the present study was designed to investigate the effect of octreotide on serum interleukin-6 of patients with acute edematous pancreatitis.

METHODOLOGY

A total of 36 patients with acute edematous pancreatitis and initiation of symptoms 12 hours before their admission were enrolled in the study; 20 were treated with octreotide 200 microg tid and 16 with octreotide 500 microg tid for five days. Blood was sampled at regular time intervals. Interleukin-6 was determined by an enzyme-immunoassay and C-reactive protein by nephelometry.

RESULTS

Mean concentrations of interleukin-6 of patients treated with octreotide 200 microg tid were 59.52 pg/mL before and 94.08, 46.25, 49.94, 58.16 and 26.08 pg/mL at 3, 6, 24, 48 and 72 hours after the start of therapy respectively. Respective values of patients treated with octreotide 500 microg tid were 57.19, 53.07, 57.83, 36.06, 54.29 and 65.49 pg/mL. Mean C-reactive protein of patients treated with octreotide 200 microg tid were 67.37 mg/L before and 48.51, 106.08 and 95.58 mg/L at 24, 48 and 72 hours after the start of therapy respectively. Respective values of patients treated with octreotide 500 microg tid were 65.51, 60.56, 90.68 and 64.22 mg/L.

CONCLUSIONS

A transient, but not statistically significant, decrease of serum interleukin-6 levels was documented after administration of octreotide in the field of acute edematous pancreatitis. That decrease was earlier after the application of the 500 microg tid dose than the 200 microg tid dose. Studies with a greater number of patients are mandatory to fully clarify the effect of octreotide, if any, on acute pancreatitis.

Changes of plasma levels of gastrointestinal peptides over the course of acute pancreatitis. Any significance for the pathophysiology and treatment of acute pancreatitis?

BACKGROUND/AIMS

Acute pancreatitis may be accompanied by alterations of the secretion of pancreatic and gastrointestinal peptides as a result of pancreatic inflammation. These changes, that may constitute targets of therapeutic manipulation, led to the study of the serum levels of various pancreatic and gastrointestinal peptides over the course of acute pancreatitis before and after the administration of octreotide and ranitidine.

METHODOLOGY

Concentrations of gastrin, glucagon, vasoactive intestinal peptide, neurotensin and pancreatic polypeptide were determined by radioimmunoassay in the plasma of 22 patients with acute pancreatitis on the first, sixth and 11th day of the disease. All patients were treated with octreotide s.c. while 14 of them were also administered ranitidine i.v. Treatment was initiated after taking the first blood sample.

RESULTS

Mean gastrin levels in patients receiving ranitidine was 56.76 ng/L and in patients not receiving ranitidine 47.16 ng/L on the first day (pNS) remaining stable throughout the course of acute pancreatitis. Mean glucagon, vasoactive intestinal peptide, neurotensin and pancreatic polypeptide levels on the first day were 52.05 pmol/L, 8.90 pmol/L, 9.80 pmol/L and 22.06 pmol/L, respectively, and no changes were found through the course of acute pancreatitis.

CONCLUSIONS

Plasma levels of gastrointestinal peptides remain constant over time and they are not significantly affected by the administration of octreotide or ranitidine. However more studies are necessary to document the significance of these findings.

The significance of the dosage adjustment of octreotide in the treatment of acute pancreatitis of moderate severity

BACKGROUND/AIMS

Octreotide is a novel semisynthetic analogue of somatostatin mainly indicated for acute necrotizing pancreatitis. The aim of the present study was to define its role in the treatment of acute pancreatitis of moderate severity.

METHODOLOGY

One hundred and twenty patients were randomly assigned to three groups of treatment receiving octreotide subcutaneously 100, 200 or 300 micrograms t.i.d. for seven days. Physical examination and biochemical monitoring were performed daily.

RESULTS

No differences were found between the three groups of patients regarding the rate of rebound of leukocytosis and of the elevated serum and urine amylase levels within normal limits. Patients receiving 300 micrograms t.i.d. presented an earlier relief of pain than all others whereas patients receiving octreotide at a dose of either 200 micrograms or 300 micrograms t.i.d. had a shorter duration of hospitalization (12 days) than those receiving octreotide at 100 micrograms t.i.d. (19 days).

CONCLUSIONS

The subcutaneous administration of octreotide in acute pancreatitis of moderate severity might be of little benefit only at a dose of 200 micrograms t.i.d. or 300 micrograms t.i.d. for at least seven days.

Glucagon-like peptide-1 (7-36)-NH2: a physiological inhibitor of gastric acid secretion in man

Glucagon-like peptide (GLP)-1 (7-36)-NH2 is a peptide found in the mucosal endocrine cells of the intestine, and plasma levels of GLP-1 (7-36)-NH2 immunoreactivity show a rise after the ingestion of a fat or mixed-component meal. We investigated the effects of physiological infusion of GLP-1 (7-36)-NH2 on a submaximal gastric acid secretion in healthy volunteers at a rate known to mimic the observed postprandial rise in plasma concentrations. Corrected gastric acid output decreased to less than 50% and volume output to 33% of stimulated values. After the infusion, the secretion of gastric acid recovered immediately to preinhibition values. These results suggest a novel role for GLP-1 (7-36)-NH2 as a physiological inhibitor of gastric acid secretion in man.

Effects of preprovasoactive intestinal polypeptide-derived peptides on ileal output

Tumors associated with the Verner Morrison syndrome secrete peptide histidine methionine, its C-terminally extended variant peptide histidine valine, and vasoactive intestinal peptide. There is evidence that vasoactive intestinal peptide mediates diarrhea, but recent evidence suggested that peptide histidine methionine and peptide histidine valine may be at least as important. Infusion of vasoactive intestinal peptide, peptide histidine methionine, and peptide histidine valine into patients with ileostomies produced mean plateau plasma levels of 163, 1301, and 2106 pM, respectively, which are within the range seen in the Verner Morrison syndrome. Vasoactive intestinal peptide produced an integrated ileal output of 174 (53) g (mean [SEM]), compared with only 20 (7) g with peptide histidine methionine and 10 (3) g with peptide histidine valine. These results suggest that vasoactive intestinal peptide is substantially more important than peptide histidine methionine or peptide histidine valine in mediating diarrhea in the Verner Morrison syndrome.

Digoxin-like substance(s) interfere(s) with serum estimations of the drug in cirrhotic patients

We measured the levels of digoxin-like immunoreactivity in the serum of 40 volunteers (20 patients with liver cirrhosis and 20 healthy adults) before and after the administration of a 5-day standard regimen of digoxin. Serum digoxin levels (SDL) were evaluated with two different radioimmunoassay (RIA) kits--Amerlex Digoxin 125I RIA and Digoxin 125I RIA. Digoxin was detectable by each RIA kit in 10 and 15% of controls and 50 and 60% of cirrhotic patients before the administration of the drug, respectively. At the end of the treatment with digoxin, SDL were significantly higher in cirrhotics when compared with those of controls. This study provides evidence that digoxin-like substance(s) is (are) implicated in the detection of high SDL in patients with histologically confirmed liver cirrhosis.

Peptide histidine valine-42 stimulates gastric acid secretion in man

The effect of peptide histidine valine-42 (PHV-42) on gastric acid secretion was studied in man. PHV-42 was infused into 5 healthy volunteers at a dose of 10 pmol/kg/min. This dose caused a significant stimulation of basal gastric acid and potassium output. There were no significant changes in circulating gastrin throughout the infusion. In 2 subjects with a background of submaximal pentagastrin stimulation, PHV-42 infusion at the same dose did not alter acid secretion in either subject. The previous observation that PHV-42 is found particularly in the stomach and the new finding that it stimulates basal gastric secretion suggest the possibility that PHV-42 could have a role in local control of acid secretion.