Endocrine tumours of the stomach

Long-Term Proton Pump Inhibitor-Acid Suppressive Treatment Can Cause Vitamin B12 Deficiency in Zollinger-Ellison Syndrome (ZES) Patients

Whether the long-term treatment of patients with proton pump inhibitors (PPIs) with different diseases [GERD, Zollinger-Ellison syndrome (ZES), etc.] can result in vitamin B12 (VB12) deficiency is controversial. In this study, in 175 patients undergoing long-term ZES treatment with anti-acid therapies, drug-induced control acid secretory rates were correlated with the presence/absence of VB12 deficiency, determined by assessing serum VB12 levels, measurements of VB12 body stores (blood methylmalonic acid (MMA) and total homocysteine[tHYC]), and other features of ZES. After a mean of 10.2 yrs. of any acid treatment (5.6 yrs. with PPIs), 21% had VB12 deficiency with significantly lower serum and body VB12 levels (p < 0.0001). The presence of VB12 deficiency did not correlate with any feature of ZES but was associated with a 12-fold lower acid control rate, a 2-fold higher acid control pH (6.4 vs. 3.7), and acid control secretory rates below those required for the activation of pepsin (pH > 3.5). Over a 5-yr period, the patients with VB12 deficiency had a higher rate of achlorhydria (73% vs. 24%) and a lower rate of normal acid secretion (0% vs. 49%). In conclusion, in ZES patients, chronic long-term PPI treatment results in marked acid hyposecretion, resulting in decreased serum VB12 levels and decreased VB12-body stores, which can result in VB12 deficiency.

Quantitative characterization of duodenal gastrinoma autofluorescence using multiphoton microscopy

BACKGROUND

Duodenal gastrinomas (DGASTs) are neuroendocrine tumors that develop in the submucosa of the duodenum and produce the hormone gastrin. Surgical resection of DGASTs is complicated by the small size of these tumors and the tendency for them to develop diffusely in the duodenum. Endoscopic mucosal resection of DGASTs is an increasingly popular method for treating this disease due to its low complication rate but suffers from poor rates of pathologically negative margins. Multiphoton microscopy can capture high-resolution images of biological tissue with contrast generated from endogenous fluorescence (autofluorescence [AF]) through two-photon excited fluorescence (2PEF). Second harmonic generation is another popular method of generating image contrast with multiphoton microscopy (MPM) and is a light-scattering phenomenon that occurs predominantly from structures such as collagen in biological samples. Some molecules that contribute to AF change in abundance from processes related to the cancer disease process (e.g., metabolic changes, oxidative stress, and angiogenesis).

STUDY DESIGN/MATERIALS AND METHODS

MPM was used to image 12 separate patient samples of formalin-fixed and paraffin-embedded duodenal gastrinoma slides with a second-harmonic generation (SHG) channel and four 2PEF channels. The excitation and emission profiles of each 2PEF channel were tuned to capture signal dominated by distinct fluorophores with well-characterized fluorescent spectra and known connections to the physiologic changes that arise in cancerous tissue.

RESULTS

We found that there was a significant difference in the relative abundance of signal generated in the 2PEF channels for regions of DGASTs in comparison to the neighboring tissues of the duodenum. Data generated from texture feature extraction of the MPM images were used in linear discriminant analysis models to create classifiers for tumor versus all other tissue types before and after principal component analysis (PCA). PCA improved the classifier accuracy and reduced the number of features required to achieve maximum accuracy. The linear discriminant classifier after PCA distinguished between tumor and other tissue types with an accuracy of 90.6%-93.8%.

CONCLUSIONS

These results suggest that multiphoton microscopy 2PEF and SHG imaging is a promising label-free method for discriminating between DGASTs and normal duodenal tissue which has implications for future applications of in vivo assessment of resection margins with endoscopic MPM.

Clinical Outcomes of Endoscopic Treatment for Type 1 Gastric Neuroendocrine Tumor

BACKGROUND

Although the rate of early detection and endoscopic treatment of gastric neuroendocrine tumors (NETs) is steadily increasing, there are insufficient studies on the long-term outcomes of endoscopic treatment. Therefore, we aimed to investigate the clinical features and long-term outcomes of endoscopic treatment for type 1 gastric NETs.

METHODS

Subjects who underwent endoscopic treatment for gastric NETs between March 1997 and December 2015 were included. Clinical features and endoscopic treatment outcomes were retrospectively investigated by reviewing medical records.

RESULTS

In total, 125 subjects underwent endoscopic treatment including forceps biopsy (n = 21), argon plasma coagulation (n = 1), endoscopic mucosal resection (EMR, n = 62), and endoscopic submucosal dissection (ESD, n = 41). In total, 103 patients with 114 lesions, who underwent EMR or ESD, were analyzed to evaluate endoscopic and oncologic outcomes. The rates of en bloc resection in the EMR and ESD groups were 91.5% and 97.7%, respectively. Complete resection rates were significantly higher in the ESD group than in the EMR group; it was also higher in < 1-cm small-sized lesions than in 1-2-cm large-sized lesions. Adverse events were similar between the two groups. During a median follow-up period of 63 months, local recurrence rates were 6.5% and 2.4% in the EMR and ESD groups, respectively, and the disease-free survival rate did not differ significantly between the groups.

CONCLUSION

Endoscopic treatment for type 1 gastric NETs less than 2 cm in diameter and confined to mucosal and submucosal layers could be an effective and safe treatment strategy based on the favorable long-term outcome.

Surgical treatment for gastrointestinal neuroendocrine tumors

Neuroendocrine tumors (NETs) are rare neoplasms, with an estimated annual incidence of 6.9/100 000. They arise from cells of the diffuse endocrine system, which are mainly dispersed throughout the gastrointestinal (GI), pancreatic, and respiratory tracts. The incidence of GI-NETs has recently begun to show a steady increase. According to the Surveillance, Epidemiology, and End Results database, 53% of patients with NETs present with localized disease, 20% with locoregional disease, and 27% with distant metastases at the time of diagnosis. Surgery is the mainstay for the treatment of locoregional GI-NETs. Endoscopic resection is an option for well-differentiated early GI-NETs, which are thought to very rarely metastasize to lymph nodes. A lesion that is technically difficult to resect via endoscopy is an indication for local resection (partial resection without lymph node dissection). GI-NETs with possible lymph node metastasis is an indication for enterectomy with lymph node dissection. For NETs with metastatic lesions, cytoreduction surgery can control hormonal hypersecretion and alleviate symptoms; therefore, cytoreduction surgery is recommended. The indications for surgery vary and are based on the organ where the NET arose; therefore, an understanding of the patient's clinical state and individualized treatment that is based on the characteristics of the patient's GI-NET is needed. This review summarizes surgical treatments of GI-NETs in each organ.

Gastrointestinal neuroendocrine tumors in 2020

Gastrointestinal neuroendocrine tumors are rare slow-growing tumors with distinct histological, biological, and clinical characteristics that have increased in incidence and prevalence within the last few decades. They contain chromogranin A, synaptophysin and neuron-specific enolase which are necessary for making a diagnosis of neuroendocrine tumor. Ki-67 index and mitotic index correlate with cellular proliferation. Serum chromogranin A is the most commonly used biomarker to assess the bulk of disease and monitor treatment and is raised in both functioning and non-functioning neuroendocrine tumors. Most of the gastrointestinal neuroendocrine tumors are non-functional. World Health Organization updated the classification of neuroendocrine tumors in 2017 and renamed mixed adenoneuroendocrine carcinoma into mixed neuroendocrine neoplasm. Gastric neuroendocrine tumors arise from enterochromaffin like cells. They are classified into 4 types. Only type I and type II are gastrin dependent. Small intestinal neuroendocrine tumor is the most common small bowel malignancy. More than two-third of them occur in the terminal ileum within 60 cm of ileocecal valve. Patients with small intestinal neuroendrocrine tumors frequently show clinical symptoms and develop distant metastases more often than those with neuroendocrine tumors of other organs. Duodenal and jejuno-ileal neuroendocrine tumors are distinct biologically and clinically. Carcinoid syndrome generally occurs when jejuno-ileal neuroendocrine tumors metastasize to the liver. Appendiceal neuroendocrine tumors are generally detected after appendectomy. Colonic neuroendocrine tumors generally present as a large tumor with local or distant metastasis at the time of diagnosis. Rectal neuroendocrine tumors are increasingly being diagnosed since the implementation of screening colonoscopy in 2000. Gastrointestinal neuroendocrine tumors are diagnosed and staged by endoscopy with biopsy, endoscopic ultrasound, serology of biomarkers, imaging studies and functional somatostatin scans. Various treatment options are available for curative and palliative treatment of gastrointestinal neuroendocrine tumors.

Associations of Tobacco and Alcohol Use with Risk of Neuroendocrine Tumors of the Small Intestine in Utah

BACKGROUND

Incidence of small-intestine neuroendocrine tumors (SINT) has been increasing in the United States over the past 40 years, with higher incidence in Utah than elsewhere. As information about how these tumors arise is limited, elucidating lifestyle factors associated with SINT in a statewide cohort could potentially identify those at risk to help mitigate their effects.

METHODS

Cases of SINT with a carcinoid histology (8240 or 8241) diagnosed in Utah from 1996 to 2014 with no prior history of cancer within 5 years (n = 433) were matched to population controls (1:10 ratio). Tobacco and alcohol exposures before case diagnosis were identified from International Classification of Diseases codes in statewide medical records and from self-reported data captured at patient encounters beginning in 1996. Multivariate logistic regression was used to estimate risk of SINT associated with tobacco and alcohol in cases compared with controls.

RESULTS

An increased risk of SINT was observed in tobacco-exposed individuals compared with unexposed [OR, 1.44; 95% confidence interval (CI), 1.11-1.86; P = 0.006]. Those who were exposed to alcohol exhibited an increased risk of SINT (OR, 1.62; 95% CI, 1.05-2.49; P = 0.03).

CONCLUSIONS

This study supports tobacco and alcohol use as risk factors for SINT, independent of family history. However, low rates of smoking and alcohol use in Utah coupled with higher rates of SINT suggest other factors may contribute to development of these tumors.

IMPACT

Although tobacco and alcohol modestly contribute to risk, our study suggests in addition to greater detection of tumors, other as-of-yet undefined exposures may drive rising SINT incidence.

Clinical characteristics of early neuroendocrine carcinoma in stomach: A case report and review of literature

INTRODUCTION

Gastric neuroendocrine carcinoma (NEC) is rare. It is considered to be aggressive and has a poor prognosis since the diagnosis is usually made at its advanced stage. However, the survival rate is increased in some early gastric NECs. This study showed a case and reviewed the clinical characteristics of early NECs in stomach.

PATIENT CONCERNS

A 38-year-old man displayed no symptoms and underwent the gastric endoscopy test for his health examination, which showed a red slightly depressed lesion 1.0 cm in size on the lesser curvature of gastric cardia. Magnifying endoscopy with narrow-band imaging (NBI) revealed a clear demarcation and an irregular mesh in vessels within the depressed area. The background mucosa was negative for atrophic gastritis and Helicobacter Pylori infection. A contrast-enhanced computed tomography (CT) scan disclosed no obvious thickening of stomach and lymphadenopathy. Blood tests and physical examination were unremarkable. He had not received any surgical treatment and denied a family history of cancer and any genetic disorders. The pathologic result of biopsy from the lesion was suspicious of superficial carcinoma. Then endoscopic submucosal dissection (ESD) was performed.

DIAGNOSIS

Gastric NEC G3 in the early stage (T1aN0M0).

INTERVENTIONS

Concerning this patient's situation, we considered the ESD as a curable treatment. And no radical surgery or adjuvant chemotherapy was arranged.

OUTCOMES

The patient is doing well and displays no recurrence for 11 months, who is still in follow-up.

LESSONS SUBSECTIONS AS PER STYLE

The early diagnosis and effective treatment by endoscopy would contribute to improve the prognosis of gastric NECs.

Gastroenteropancreatic Neuroendocrine Tumors

Neuroendocrine tumors (NETs) are heterogeneous malignancies arising from the diffuse neuroendocrine system. They frequently originate in the gastroenteropancreatic (GEP) tract and the bronchopulmonary tree, and their incidence has steadily increased in the last 3 decades. Fundamental biologic and genomic differences underlie the clinical heterogeneity of NETs, and distinct molecular features characterize NETs of different grades and different primary sites. Although surgery remains the cornerstone of treatment for localized tumors, systemic treatment options for patients with metastatic NETs have expanded considerably. Somatostatin analogs have demonstrated both antisecretory and antitumor efficacy. Peptide receptor radionuclide therapy with lutetium-177 dotatate (¹⁷⁷ Lu-DOTATATE) has been approved for advanced GEP-NETs. The antitumor activity of everolimus has been demonstrated across a wide spectrum of NETs, and the antiangiogenic agent sunitinib has been approved for pancreatic NETs (pNETs). Chemotherapy with temozolomide and capecitabine has recently demonstrated an unprecedented prolongation of progression-free survival in a randomized trial of pNETs. Multiple retrospective series have reported the efficacy of liver-directed therapies both for palliating symptoms of hormone excess and for controlling tumor growth. Telotristat, an oral inhibitor of tryptophan hydroxylase, has been shown to reduce diarrhea in patients with carcinoid syndrome. Defining the therapeutic algorithm and identifying biomarkers predictive of response to treatments are among the main priorities for the next decade of research in the NET field.

SSAT State-of-the-Art Conference: Current Surgical Management of Gastric Tumors

INTRODUCTION

The current era of gastric surgery is marked by low morbidity and mortality rates, innovative strategies to approach resections with a minimally invasive fashion or hyperthermic intraperitoneal chemotherapy (HIPEC), as well as improved understanding of the biology of sporadic and hereditary stromal, neuroendocrine, and epithelial malignancies.

METHODS

In 2017, the Society for Surgery of the Alimentary Tract convened a State-of-the-Art Conference on Current Surgical Management of Gastric Tumors with both international experts and emerging leaders in the field of gastric surgery.

RESULTS

Martin D. McCarter, MD of the University of Colorado discussed the current management of gastric gastrointestinal stromal tumors (GIST). Kaitlyn J. Kelly, MD of the University of California, San Diego discussed the management of gastric carcinoid tumors. Jeffrey A. Norton of Stanford University discussed recent advances in the management of gastric adenocarcinoma including a focus on hereditary diffuse gastric cancer (HDGC). Joseph Kim, MD of Stony Brook University discussed a systematic approach to minimally invasive gastrectomy for cancer. Joyce Wong, MD of Pennsylvania State University discussed the role for cytoreductive surgery (CRS) and HIPEC for gastric adenocarcinoma.

CONCLUSIONS

This review provides gastrointestinal surgeons with a concise update on the current surgical management of gastric tumors.

Type 1 Gastric Carcinoid in the Indian Population and Its Association with Multifocal Gastric Atrophy

Aim

Recent studies have shown an increase in the incidence of gastric neuroendocrine tumors (NETs) (carcinoids). This may be attributable to the frequent employment of endoscopy in clinical practice and the increasing use of proton pump inhibitors. From the literature that is available, it is interesting to note that the profile of patients with gastric carcinoids is different in the Asian population when compared to the western societies. As limited data is available from India, we evaluated retrospectively the clinical profile and pathology of gastric carcinoids presenting to our hospital.

Materials and methods

A total of 31 patients with gastric carcinoids who presented to our institution from 2006 till 2013 were included in this study. The clinical data were obtained from the case files and the histopathology slides were reviewed.

Results

Gastric carcinoids constituted about 32% of all gastrointestinal (GI) NETs and were second only to duodenal carcinoids in frequency. Men were more commonly affected (74%) and the majority were of type 1 (90%). Multifocal gastric atrophy with intestinal metaplasia was additional features seen in the majority of cases with type 1 carcinoids.

Conclusion

This study, one of the largest series reported from India, shows that the frequency and profile of gastric carcinoids is different in this population when compared to the west. It also raises the possibility that Helicobacter pylori induced multifocal gastric atrophy might be a triggering factor for the most common type 1 gastric carcinoid rather than autoimmune gastritis.

Clinical significance

Eradication of H.pylori may be a potential preventive strategy for the occurrence of gastric carcinoids.

How to cite this article

Ananthamurthy A, Correa M, Patil M. Type 1 Gastric Carcinoid in the Indian Population and Its Association with Multifocal Gastric Atrophy. Euroasian J Hepato-Gastroenterol 2016;6(2):106-110.

Gastric carcinoid tumor in a 14-year old girl

Gastric carcinoid tumors (GCT) are rare lesions that constitute 2.6-8.7% of all gastrointestinal carcinoids, mostly affect middle-aged females but the incidence in children is unknown. We present a 14-year-old girl, with GCT. She was treated with recombinant human growth hormone (GH) for complete GH deficiency, and endoscopy was performed to identify iron-deficiency anemia. Upper gastrointestinal endoscopy revealed a gastric polyp, and biopsies were compatible with GCT.

GEP-NETS update: a review on surgery of gastro-entero-pancreatic neuroendocrine tumors

The incidence of neuroendocrine tumors (NETs) has increased in the last decades. Surgical treatment encompasses a panel of approaches ranging from conservative procedures to extended surgical resection. Tumor size and localization usually represent the main drivers in the choice of the most appropriate surgical resection. In the presence of small (<2 cm) and asymptomatic nonfunctioning NETs, a conservative treatment is usually recommended. For localized NETs measuring above 2 cm, surgical resection represents the cornerstone in the management of these tumors. As they are relatively biologically indolent, an extended resection is often justified also in the presence of advanced NETs. Surgical options for NET liver metastases range from limited resection up to liver transplantation. Surgical choices for metastatic NETs need to consider the extent of disease, the grade of tumor, and the presence of extra-abdominal disease. Any surgical procedures should always be balanced with the benefit of survival or relieving symptoms and patients' comorbidities.

Neuroendocrine tumors of the gastrointestinal tract: Case reports and literature review

Neuroendocrine tumors (NET) previously called carcinoid tumors are neoplasms of enterochromaffin/neuroendocrine cell origin which display neurosecretory capacity that may result in the carcinoid syndrome. The annual incidence of patients with NET is 8.4 per 100000; yet many NET remain asymptomatic and clinically undetected. A majority of NET follows a benign course; however, some will display malignant characteristics. NET most commonly occur in the gastrointestinal tract (67%) and bronchopulmonary system (25%). Gastrointestinal NET occur within the stomach, small intestine, liver, and rectum. We report a retrospective study of 11 subjects: Eight with benign carcinoid tumors: duodenal bulb (n = 2), terminal ileum (n = 1), sigmoid colon (n = 2), and rectum (n = 3); three with malignant carcinoid: liver (n = 1) and intra-abdominal site (n = 2). The diagnosis, endoscopic images, outcome, treatment and review of the literature are presented.

Gastric carcinoid in the absence of atrophic body gastritis and with low Ki67 index: a clinical challenge

BACKGROUND

Gastric carcinoids (GCs) represent 23% of all digestive neuroendocrine tumors (NETs). They can be distinguished into three types: type I (in the presence of atrophic body gastritis, ABG), type II (in the presence of Zollinger-Ellison/multiple endocrine neoplasia type I syndrome), type III (sporadic carcinoids, without any background pathology).

AIM

To describe a case of undetermined type of GCs in an Italian referral center for NETs and its prevalence among GCs during a 6-year period.

RESULTS

In a case series of 16 GCs seen at our unit between 2007 and 2012, 14 (83.3%) patients had type I carcinoid and 1 patient (6.2%) had type III carcinoid. One patient did not accomplish to the actual classification criteria. This patient had a well-differentiated carcinoid with low Ki67, but multiple gastric biopsies performed at 3-year follow-up gastroscopies excluded the presence of ABG. The patient had fundic cystic polyps, suggesting long-term use of proton pump inhibitors, possibly associated with GCs.

CONCLUSIONS

This case shows that a GC may occur in the absence of ABG and with low Ki67 index, making classification according to actual criteria difficult. Further studies are needed to better understand the occurrence of this particular type of GCs.

The efficacy of endoscopic submucosal dissection of type I gastric carcinoid tumors compared with conventional endoscopic mucosal resection

Background and Aims. Conventional endoscopic submucosal resection (EMR) of carcinoid tumors often involves the resection margin, which necessitates further intervention. Endoscopic submucosal dissection (ESD) is widely accepted for removing carcinoid tumors. We aimed to evaluate the clinical usefulness of ESD with that of EMR for resection of type I gastric carcinoid tumors. Patients and Methods. The study enrolled 62 patients (37 males, 25 females; median age, 50 years; range, 40-68 years) who were treated with EMR or ESD at three hospitals; the study group had 87 type I gastric carcinoid tumors with an estimated size of ≤10 mm. The complete resection rate and the complications associated with these two procedures were analyzed. Results. The overall ESD complete resection rate was higher than that of the EMR rate (94.9% versus 83.3%, P value = 0.174). A statistically lower vertical margin involvement rate was achieved when ESD was performed compared to when EMR was performed (2.6% versus 16.7%, P value = 0.038). The complication rate was not significantly different between the two groups. Conclusions. ESD showed a higher complete resection rate, particularly for the vertical margin, with a similar complication rate. We mildly recommend ESD rather than EMR for removing type I gastric carcinoid tumors.

New insights into the role of chronic inflammation and cytokines in the etiopathogenesis of gastroenteropancreatic neuroendocrine tumors

Although previously considered rare, recent epidemiological studies have revealed that the incidence (3.6/100,000) and prevalence (35/100,000) of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) has increased over the past few decades. Despite the progress in the understanding of GEP-NET molecular biology, there is still little advance in the early diagnosis due to lack of specific tumor markers. As the tumors are mostly detected in their late stage, they are not well controlled by either biotherapy or conventional chemotherapy, and thus represent a significant clinical issue. Chronic inflammation has been implicated in the development of GEP-NETs. This review presents recent findings that link pro-inflammatory cytokines to the molecular basis of GEP-NET tumorigenesis, leading to a more personalized approach to disease management and therapy.

Diagnostic and therapeutic role of endoscopy in gastroenteropancreatic neuroendocrine neoplasms

Gastroenteropancreatic neuroendocrine neoplasms have substantially increased over the last decades. Because of the indolent clinical course of the disease even in advance stages and the rise in the incidental diagnosis of small asymptomatic lesions, the prevalence of gastroenteropancreatic neuroendocrine neoplasms is higher than that of pancreatic, gastric and oesophageal adenocarcinomas, making them the second most prevalent cancer type of the gastrointestinal tract. This increase in the overall prevalence of gastroenteropancreatic neuroendocrine neoplasms has been paralleled by a growth in the importance of the endoscopist in the care of these patients, who usually require a multidisciplinary approach. In this manuscript the diagnostic and therapeutic role of endoscopic for gastroenteropancreatic neuroendocrine neoplasms will be reviewed.

Endoscopic resection for gastrointestinal neuroendocrine tumors

Gastrointestinal (GI) and neuroendocrine tumors (NETs) can be treated by mini-invasive endoscopic resection when localized in the superficial layers of the bowel wall and their size is <20 mm. Endoscopic diagnosis of NETs is usually incidental or suspected after clinical, laboratory or imaging findings. Endoscopic mucosal resection is the most commonly used technique for NET removal, endoscopic submucosal dissection is indicated in selected cases, while papillectomy is feasible for ampullary lesions. Histopathologic assessment of the resection margin (circumferential and deep) is important for staging. Incidence of endoscopic mucosal resection-/endoscopic submucosal dissection-related complications for removal of GI NETs are similar to those reported for other GI lesions. Endoscopic follow-up is based on histopathologic characteristics of the resected NETs and its site. NETs >20 mm in size, with penetration of the muscle layer and/or serosa are at high risk for metastases and surgical approach is recommended when feasible.

[Hyperplastic polyp with neoplastic transformation in a patient with atrophic gastritis and multiple gastric neuroendocrine tumors]

Hyperplastic gastric polyps are often found at GI endoscopy and are not considered premalignant lesions, although some cases of malignancy have been reported. Neuroendocrine tumors, conversely, are rare and account for approximately 1% to 2% of gastric polyps. Both hyperplastic gastric polyps and neuroendocrine tumors are related to gastric atrophy. The case of a hyperplastic polyp with multifocal areas of adenocarcinoma within the polyp associated to multiple gastric neuroendocrine tumors is reported.

Type I gastric carcinoids: a prospective study on endoscopic management and recurrence rate

BACKGROUND

Type I gastric carcinoids (TIGCs) are neuroendocrine neoplasms arising from enterochromaffin-like cells in atrophic body gastritis. Data regarding their evolution in prospective series are scarce, thus treatment and follow-up are not codified. Our aim was to evaluate clinical outcome and recurrence in TIGCs managed by endoscopic approach.

METHODS

33 patients (24 females; median age 65 years, range 23-81) were included and managed through endoscopic follow-up every 6-12 months, with lesion removal and multiple gastric biopsies. Baseline clinical and histological features were analyzed as risk factors by Cox regression.

RESULTS

At diagnosis, 7 tumors were intramucosal carcinoids and 26 were polyps (median diameter 5 mm, range 2-20), multiple in 17 patients. Associated severe atrophy was present in 21 cases (63.6%), while mild atrophy was found in 6 cases (18.2%). During a 46-month median follow-up, survival was 100% and no metastases occurred. One patient developed a less-differentiated carcinoid that was radically treated by surgery. 21 patients (63.6%) had recurrence after a median of 8 months, 14 of these (66.6%) had a second recurrence after a median of 8 months following the previous carcinoid removal. Median recurrence-free survival was 24 months. Neither clinical nor biochemical recurrence-predicting factors were found.

CONCLUSIONS

Although about 60% of TIGCs had recurrence after endoscopic resection, endoscopic management may be considered safe and effective.

Gastric type I carcinoid: a pilot study with human G17DT immunogen vaccination

CONTEXT

Gastric type I carcinoid is a rare neoplasm, deriving from enterochromaffin-like cells (ECL), mainly affecting women with autoimmune gastritis. The approach to treatment, either endoscopic, medical or surgical, is not well defined, particularly in multifocal tumours or carcinoids with rapid growth/frequent recurrence.

OBJECTIVE

To determine whether an anti-G17 vaccination might interfere on the natural history of gastric type I carcinoid.

SETTING

Padua teaching Hospital, outpatient clinic.

DESIGN AND PATIENTS

Three patients with type I gastric carcinoid in autoimmune gastritis were administered, after informed consent and ethic committee approval, with a vaccine against gastrin 17 (G17), a synthetic peptide that stimulates specific and high-affinity anti-G17 antibodies, and followed up endoscopically and clinically for a mean of 36 months.

MAIN OUTCOME MEASURES

Gastric histology and specifically carcinoid growth/recurrence and trend in time in gastrin, G17, pepsinogens, chromogranin A and clinical parameters.

RESULTS

Following vaccination, carcinoid regression was observed in 2/3 patients and, in one of the patients, even the disappearance of ECL hyperplasia, with a reduced ECL cells stimulation, confirmed by a significant reduction in chromogranin A levels. Regression was observed in the two patients that showed a more clear local response to the vaccine. Increased autoantibody titre was observed, but no appearance of new autoimmune diseases.

CONCLUSIONS

Anti-G17 vaccination induced regression of type I gastric carcinoid and could be considered for the treatment of this tumour, when endoscopic removal is not indicated.

Surgical treatment of gastrointestinal neuroendocrine tumors

INTRODUCTION

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are uncommon but clinically challenging and fascinating tumors. GEP-NETs present as either functional or as nonfunctional tumors. Functional tumors are commonly associated with a specific hormonal syndrome directly related to a hormone secreted by the tumor, like gastrinomas with a Zollinger-Ellison syndrome or carcinoid syndrome in patients with neuroendocrine tumors (NET) of the ileum. Nonfunctional tumors do not secrete a hormone resulting in a clinical syndrome.

METHODS

The natural course of GEP-NETs is highly variable. Small, benign neoplasms such as 90% of all insulinomas or gastric endocrine tumors type 1 are readily curable by surgical resection; however, most other GEP-NETs have a much less favorable prognosis. Patients with completely resected tumors generally have a good prognosis, and an aggressive surgical approach in patients with advanced disease may also prolong survival.

CONCLUSIONS

This review focuses on the current standards of surgical treatment of gastric endocrine tumors, NETs of the pancreas (PNET) and NETs of the ileum. Although the evidence level is low in many instances due to the lack of randomized controlled trials, important treatment recommendations can be given.

Mechanism of acid hypersecretion post curative gastrinoma resection

BACKGROUND

Some patients with Zollinger-Ellison syndrome post curative gastrinoma resection continue to show gastric acid hypersecretion; however, the mechanism is unknown.

AIM

The aim of this study was to prospectively study acid secretion following curative gastrinoma resection and analyze factors contributing in patients with Zollinger-Ellison syndrome.

METHODS

Fifty patients cured post gastrinoma resection were studied with serial assessments of acid secretory status, cure status and ECL-cell status/activity (with serial biopsies, CgA, urinary N-MIAA). Correlative analysis was performed to determine predictive factors.

RESULTS

Hypersecretion occurred in 31 patients (62%) and 14 had extreme-hypersecretion. There was an initial decline (3-6 months) in BAO/MAO, which then remained stable for eight years. Preoperative BAO correlated with the postoperative secretion, but not other clinical, tumoral, laboratory variables, the degree of postoperative acid suppression or type of antisecretory drug needed. Hypersecretors had greater postoperative ECL changes (P=0.005), serum CGA (P=0.009) and 24-h urinary N-MIAA (P=0.0038).

CONCLUSIONS

Post curative resection, gastric hypersecretion persists long term (mean 8 years) in 62% of patients and in 28% it is extreme, despite normogastrinemia. No preoperative variable except BAO correlates with postresection hypersecretion. The persistent increased ECL-cell extent post curative resection suggests prolonged hypergastrinemia can lead to changes in ECL-cells that are either irreversible in humans or sustained by unknown mechanisms not involving fasting hypergastrinemia and which can result in hypersecretion, in a proportion of which it can be extreme. Whether similar findings may occur in patients with idiopathic GERD treated for prolonged periods (>10 years) with PPIs, at present, is unknown.

NANETS treatment guidelines: well-differentiated neuroendocrine tumors of the stomach and pancreas

Well-differentiated neuroendocrine tumors (NETs) of the stomach and pancreas represent 2 major subtypes of gastrointestinal NETs. Historically, there has been little consensus on the classification and management of patients with these tumor subtypes. We provide an overview of well-differentiated NETs of the stomach and pancreas and describe consensus guidelines for the treatment of patients with these malignancies.

Typical carcinoids and neuroendocrine carcinomas of the stomach: differing clinical courses and prognoses

BACKGROUND

Gastric endocrine tumors are usually classified as 3 types of well-differentiated endocrine tumors (typical carcinoids or carcinoids) and poorly differentiated carcinomas (neuroendocrine carcinomas [NECs]).

METHODS

From 1993 to 2008, 97 patients (73 men and 24 women) were diagnosed with gastric neuroendocrine tumors at the Asan Medical Center.

RESULTS

Of the 45 patients with typical carcinoids, 37 underwent surgery (eg, endoscopic resection). Of the 52 patients with NECs, 43 underwent surgery (eg, radical gastrectomy). One patient died of recurrence of the typical carcinoids, whereas 26 patients with NECs died of related diseases (P < .05). The rates of survival and recurrence did not significantly differ by type of typical carcinoid (P > .05).

CONCLUSIONS

Regardless of the type, carcinoids that are not yet advanced can be effectively treated with minimal endoscopic or laparoscopic surgery. However, all NECs and advanced carcinoids should be treated with radical gastrectomy.

Carcinoid tumors

Carcinoid tumors, which arise from the enterochromaffin cells of the gastrointestinal tract, encompass a diverse group of neoplasms. Once thought to be "carcinoma-like," these neoplasms exhibit a biologic behavior that varies from an indolent, benign course to an aggressive, rapidly progressive, and deadly disease. Today the term carcinoid is reserved for neuroendocrine tumors arising from the small bowel or neuroendocrine tumors that can cause carcinoid syndrome. This newer terminology has yet to be universally adopted, adding to the confusion in the literature. For the general surgeon there are several "carcinoid" tumors that he or she must be familiar with because many of these lesions are encountered during emergency laparotomies or incidentally discovered during investigation for vague abdominal pain. This review focuses on the gastrointestinal neuroendocrine tumors that general surgeons are likely to encounter during their career.

En-bloc resection of multiple type 1 gastric carcinoid tumors by endoscopic multi-band mucosectomy

BACKGROUND AND AIM

Gastric carcinoid tumors are rare but increasing in incidence. Current recommendations suggest endoscopic resection for type I carcinoids found in the stomach, however reports of incomplete resection have led to difficulty planning future management. Our purpose was to describe the application of the endoscopic multi-band mucosectomy (MBM) device to achieve en-bloc resection of multiple gastric carcinoid tumors.

METHODS

Over a 30-month period (June 2006-January 2009) eight patients attending for endoscopic assessment of gastric carcinoid tumors were identified at two tertiary referral centers. Patients underwent endoscopic resection of the carcinoids with an MBM device. En-bloc specimens underwent histological evaluation for identification and tumor resection margins. Patients with type I carcinoids were subsequently enrolled in an endoscopic follow-up program.

RESULTS

A total of 34 gastric carcinoid tumors were removed from eight patients. On histological analyses seven out of eight patients were diagnosed with type I tumors. In the remaining patient a single, sporadic (type III) gastric carcinoid was diagnosed. No complications of severe bleeding or perforation occurred. All specimens were shown to have clear deep and peripheral histological resection margins.

CONCLUSION

Complete 'en-bloc' endoscopic resection of multiple 'type I' gastric carcinoid tumors can be safely and easily performed with an MBM technique.

Gastric carcinoids: Between underestimation and overtreatment

Gastric carcinoids (GCs), which originate from gastric enterochromaffin-like (ECL) mucosal cells and account for 2.4% of all carcinoids, are found increasingly in the course of upper gastrointestinal tract endoscopy. Current nosography includes those occurring in chronic conditions with hypergastrinemia, as the type 1 associated with chronic atrophic gastritis, and the type 2 associated with Zollinger-Ellison syndrome in multiple endocrine neoplasia type 1, and type 3, which is unrelated to hypergastrinemia and is frequently malignant, with distant metastases. The optimal clinical approach to GCs remains to be elucidated, depending upon type, size and number of carcinoids. While there is agreement concerning the treatment of type 3 carcinoids, for types 1 and 2, current possibilities include simple surveillance, endoscopic polypectomy, surgical excision, associated or not with surgical antrectomy, or total gastrectomy. Moreover, the recent introduction of somatostatin analogues represents a therapeutic option of possibly outstanding relevance.

Gastrin increases mcl-1 expression in type I gastric carcinoid tumors and a gastric epithelial cell line that expresses the CCK-2 receptor

Elevated serum concentrations of the hormone gastrin are associated with the development of gastric carcinoid tumors, but the mechanisms of tumor development are not fully understood. We hypothesized that the antiapoptotic effects of gastrin may be implicated and have therefore investigated the role of antiapoptotic members of the bcl-2 family of proteins. AGS-G(R) human gastric carcinoma cells stably transfected with the CCK-2 receptor were used to assess changes in the expression of bcl-2 family members following gastrin treatment and the function of mcl-1 during apoptosis was investigated by use of small-interfering RNA (siRNA). Treatment of AGS-G(R) cells with 10 nM gastrin for 6 h caused maximally increased mcl-1 protein abundance. Gastrin-induced mcl-1 expression was inhibited by the transcription inhibitor actinomycin D and by the protein synthesis inhibitor cycloheximide. Downstream signaling of mcl-1 expression occurred via the CCK-2 receptor, protein kinase C, and MAP kinase pathways, but not via PI 3-kinase. Transfection with mcl-1 siRNA significantly suppressed mcl-1 protein expression and abolished the antiapoptotic effects of gastrin on serum starvation-induced apoptosis. Mcl-1 protein expression was also specifically increased in the type I enterochromaffin-like cell carcinoid tumors of 10 patients with autoimmune atrophic gastritis and hypergastrinemia. Gastrin therefore signals via the CCK-2 receptor, protein kinase C, and MAP kinase to induce expression of antiapoptotic mcl-1 in AGS-G(R) cells, and mcl-1 expression is also increased in human hypergastrinemia-associated type I gastric carcinoid tumors. Gastrin-induced mcl-1 expression may therefore be an important mechanism contributing toward type I gastric carcinoid development.

Pancreatic endocrine tumors-c-erb B2 (Her-2/neu), bcl-2, and p-53 immunohistochemical testing and their value in assessing prognosis

INTRODUCTION

In an attempt to identify better prognostic factors, and the genetic basis of pancreatic endocrine tumors (PETs), we evaluated immunohistochemical reactivity for c-erb B2 (Her-2/neu), bcl-2, and p53.

METHODS AND MATERIALS

Two pathologists reviewed hematoxylin and eosin slides and immunohistochemical stains from 28 cases, 27 tumors and 1 nesidioblastosis. Using WHO criteria for malignancy (presence of local or lymphovascular invasion and/or metastases), cases were divided into malignant (20 cases) and benign or uncertain (8 cases). Nuclear staining in >1% of cells was considered positive for p53 and bcl-2, whereas membranous staining was considered positive for c-erb B2 (Her-2/neu).

RESULTS

All cases were nonimmunoreactive with anti-c-erb B2 (Her-2/neu), but focal granular or diffuse cytoplasmic staining was seen in occasional neoplasms. One malignant PET showed reactivity with anti-p53, whereas all others were negative. bcl-2 reactivity was identified in 15/28 cases: 9/20 malignant PETs and 6/8 others were positive.

CONCLUSIONS

c-erb B2 (Her-2/neu) and p53 are not useful prognostic factors in PET. c-erb B2 (Her-2/neu) staining must be carefully evaluated to avoid the misinterpretation of artifactual/background staining. bcl-2 is occasionally expressed in PET, but the significance of this finding is still to be determined.

A composite adenoendocrine carcinoma of the stomach arising from a neuroendocrine tumor

Gastric neuroendocrine tumors (carcinoids) are relatively uncommon neoplasms. Some 70 to 80% of these lesions occur in patients with autoimmune body gastritis. This disorder, however, is also a risk factor for the development of conventional gastric adenocarcinomas. We report a case of a patient with autoimmune body gastritis and a well-differentiated neuroendocrine tumor of the stomach, which was removed with endoscopic full-thickness resection in sano upon signs of invasive growth several years after its first diagnosis. Histological examination surprisingly showed a composite glandular-endocrine gastric carcinoma. We discuss the histopathological genesis of the tumor and provide evidence that endoscopic full-thickness resection might be an oncologically appropriate minimally invasive treatment for such gastric lesions.

Peptide receptor radionuclide therapy with 177Lu-octreotate in patients with foregut carcinoid tumours of bronchial, gastric and thymic origin

PURPOSE

Foregut carcinoid tumours have a different embryological origin than other gastroenteropancreatic neuroendocrine tumours (GEP NETs). In the total group of GEP NETs (n = 131), treatment with (177)Lu-octreotate resulted in tumour remission in 47% of patients, with a median time to progression (TTP) of >36 months. As patients with foregut carcinoids may respond differently, we here present the effects of this treatment in a subgroup of patients with foregut carcinoids of bronchial, gastric or thymic origin.

METHODS

Nine patients with bronchial, five with gastric and two with thymic carcinoids were treated. All patients had metastasised disease. The intended cumulative dose of (177)Lu-octreotate was 22.2-29.6 GBq. Southwest Oncology Group criteria were used for response evaluation.

RESULTS

Bronchial carcinoids: Five patients had partial remission, one had minor response (MR, tumour size reduction: > or =25%, <50%), two had stable disease (SD) and one had progressive disease (PD). Median TTP was 31 months. Gastric carcinoids: One patient had complete remission, one had MR and two had SD, including one with PD at baseline. One patient developed PD. Thymic carcinoids: One patient had SD. In the other patient, disease remained progressive. All patients: Overall remission rate was 50%, including MR.

CONCLUSION

(177)Lu-octreotate treatment can be effective in patients with bronchial and gastric carcinoids. Its role in thymic carcinoids cannot be determined yet because of the limited number of patients. The overall remission rate of 50% in patients with the studied foregut carcinoids is comparable to that in the total group of GEP NETs.

Long-term endoscopic and clinical follow-up of untreated type 1 gastric neuroendocrine tumours

BACKGROUND AND AIMS

Type 1 gastric neuroendocrine tumour surveillance and treatment are a matter of debate. Endoscopic, or surgical, resection and chronic somatostatin analog therapy have been proposed. Based on the favourable behaviour of this neoplasm, we performed an endoscopic and clinical follow-up in 11 patients affected by type 1 gastric neuroendocrine tumours, avoiding any specific treatment.

METHODS

Between 1994 and 2006, we prospectively recorded the data of 11 untreated patients with type 1 gastric neuroendocrine tumours who underwent an endoscopic and clinical follow-up. All the patients were also evaluated by means of an abdominal computed tomography scan, somatostatin receptor scintigraphy and blood tests.

RESULTS

During the follow-up (median 54 months, range 9-136), the endoscopic picture of 4 (36%) out of 11 patients changed in terms of increased number of lesions. In none of the cases were detected any lesions that exceeded 10mm in diameter, and none of the patients demonstrated any evidence of local or distant metastases.

CONCLUSIONS

Our data confirm the literature data of the indolent behaviour of type 1 gastric neuroendocrine tumours and suggest that a careful endoscopic follow-up, without any treatment, might represent a reasonable and safe option in selected patients.

Surgery on neuroendocrine tumours

Neuroendocrine tumours of the gastrointestinal tract and pancreas present a major challenge to physicians in their recognition and treatment requirements, and surgical treatment of these tumours has become increasingly important for symptom palliation and survival. For some carcinoid tumours the extent of surgery may depend on tumour size. Midgut carcinoid is the most common cause of the carcinoid syndrome, requiring surgery for primary and mesenteric tumours to minimize the risk for abdominal complications but also for removal of liver metastases to palliate hormonal symptoms. Among endocrine pancreatic tumours, insulinoma and gastrinoma often cause severe symptoms of hormone excess despite their inconspicuous size, but they can be successfully removed with improved pre- and intraoperative localization. Other tumours--glucagonoma, VIPoma, and non-functioning endocrine pancreatic tumours--are often large or metastasizing, but generally require surgical debulking to alleviate hormonal symptoms and have favourable survival.

Gastrin - active participant or bystander in gastric carcinogenesis?

Gastrin is a pro-proliferative, anti-apoptotic hormone with a central role in acid secretion in the gastric mucosa and a long-standing association with malignant progression in transgenic mouse models. However, its exact role in human gastric malignancy requires further validation. Gastrin expression is tightly regulated by two closely associated hormones, somatostatin and gastrin-releasing peptide, and aspects of their interaction may be deregulated during progression to gastric adenocarcinoma. Furthermore, agonists and antagonists of the receptors for all three hormones have shown modest clinical efficacy against gastric adenocarcinoma, which might provide useful information on the future combined use of these agents.

Review article: Pathogenesis and management of gastric carcinoid tumours

BACKGROUND

Gastric carcinoid tumours are rare, but are increasing in incidence.

AIM

To discuss tumour pathogenesis and outline current approaches to patient management.

METHODS

Review of published articles following a Pubmed search.

RESULTS

Although interest in gastric carcinoids has increased since it was recognized that they are associated with achlorhydria, to date there is no definite evidence that humans taking long-term acid suppressing medication are at increased risk. Type I tumours are associated with autoimmune atrophic gastritis and hypergastrinaemia, type II are associated with Zollinger-Ellison syndrome, multiple endocrine neoplasia-1 and hypergastrinaemia and sporadic type III carcinoids are gastrin-independent and carry the worst prognosis. Careful investigation of these patients is required, particularly to identify the tumour type, the source of hypergastrinaemia and the presence of metastases. Treatment can be directed at the source of hypergastrinaemia if type I or II tumours are still gastrin responsive and not growing autonomously. Type III tumours should be treated surgically.

CONCLUSIONS

Advances in our understanding of the pathogenesis of gastric carcinoids have led to recent improvements in investigation and management. Challenges remain in identifying the genetic and environmental factors, in addition to hypergastrinaemia, that are responsible for tumour development in susceptible patients.

Prevalence and evaluation of B12 deficiency in patients with autoimmune thyroid disease

BACKGROUND

Patients with autoimmune thyroid disease (AITD) have a higher prevalence of pernicious anemia compared with the general population. Clinical signs of B12 deficiency may be subtle and missed, particularly in patients with known autoimmune disease. We assessed the prevalence of vitamin B12 deficiency in patients with AITD and whether their evaluation may be simplified by measuring fasting gastrin levels.

METHODS

Serum B12 levels was measured in 115 patients with AITD (7 men and 108 women), with a mean age of 47 +/- 15 years. In patients with low serum B12 levels (< or =133 pmol/L), fasting serum gastrin and parietal cell antibodies (PCA) were measured.

RESULTS

Thirty-two patients (28%) with AITD had low B12 levels. Fasting serum gastrin was measured in 26 and was higher than normal in 8 patients. PCA were also measured in 27 patients with B12 deficiency and were positive in 8 patients. Five patients with high gastrin levels underwent gastroscopy with biopsy, and atrophic gastritis was diagnosed in all. The prevalence of pernicious anemia as assessed by high serum gastrin levels in patients with low B12 was 31%.

CONCLUSIONS

Patients with AITD have a high prevalence of B12 deficiency and particularly of pernicious anemia. The evaluation of B12 deficiency can be simplified by measuring fasting serum gastrin and, if elevated, referring the patient for gastroscopy.

Carcinoid tumors

Carcinoid tumors can present a difficult diagnostic and therapeutic dilemma. Despite their reputation as indolent tumors, they frequently metastasize and can cause significant symptomatology. The only curative therapy remains surgical resection. The prognosis and treatment of carcinoids vary based on location and histology, and therapy must be tailored to each patient.