Calcium-sensing receptor activator cinacalcet for treatment of cyclic nucleotide-mediated secretory diarrheas

Cyclic nucleotide elevation in intestinal epithelial cells is the key pathology causing intestinal fluid loss in secretory diarrheas such as cholera. Current secretory diarrhea treatment is primarily supportive, and oral rehydration solution is the mainstay of cholera treatment. There is an unmet need for safe, simple and effective diarrhea treatments. By promoting cAMP hydrolysis, extracellular calcium-sensing receptor (CaSR) is a regulator of intestinal fluid transport. We studied the antidiarrheal mechanisms of FDA-approved CaSR activator cinacalcet and tested its efficacy in clinically relevant human cell, mouse and intestinal organoid models of secretory diarrhea. By using selective inhibitors, we found that cAMP agonists-induced secretory short-circuit currents (Isc) in human intestinal T84 cells are mediated by collective actions of apical membrane cystic fibrosis transmembrane conductance regulator (CFTR) and Clc-2 Cl- channels, and basolateral membrane K+ channels. 30 μM cinacalcet pretreatment inhibited all 3 components of forskolin and cholera toxin-induced secretory Isc by ∼75%. In mouse jejunal mucosa, cinacalcet inhibited forskolin-induced secretory Isc by ∼60% in wild type mice, with no antisecretory effect in intestinal epithelia-specific Casr knockout mice (Casr-flox; Vil1-cre). In suckling mouse model of cholera induced by oral cholera toxin, single dose (30 mg/kg) oral cinacalcet treatment reduced intestinal fluid accumulation by ∼55% at 20 hours. Lastly, cinacalcet inhibited forskolin-induced secretory Isc by ∼75% in human colonic and ileal organoids. Our findings suggest that CaSR activator cinacalcet has antidiarrheal efficacy in distinct human cell, organoid and mouse models of secretory diarrhea. Considering its excellent clinical safety profile, cinacalcet can be repurposed as a treatment for cyclic nucleotide-mediated secretory diarrheas including cholera.

All you need to know about VIPoma: Review on the latest studies

Vasoactive intestinal peptide secreting tumor (VIPoma) is a rare mostly malignant neuroendocrine tumor that is characterized by watery diarrhea, hypokalemia and achlorhydria due to the nonregulated increased secretion of VIP. VIPomas ar diagnosed by the presence of the most common symptoms, laboratory analysis of blood and stool, radiological imaging and immunohistochemical findings. Primary treatment includes fluid replacement, electrolyte balance correction, pharmacological treatment with somatostatin analogs, surgical resection and chemotherapy. This review aims to provide an insight into the latest research on VIPoma epidemiology, pathophysiology, diagnostics and treatment.

European Neuroendocrine Tumor Society 2023 guidance paper for functioning pancreatic neuroendocrine tumour syndromes

This ENETS guidance paper aims to provide practical advice to clinicians for the diagnosis, treatment and follow-up of functioning syndromes in pancreatic neuroendocrine tumours (NET). A NET-associated functioning syndrome is defined by the presence of a clinical syndrome combined with biochemical evidence of inappropriately elevated hormonal levels. Different hormonal syndromes can be encountered in pancreatic NET patients, including insulinoma, gastrinoma as well as the rare glucagonoma, VIPoma, ACTHoma, PTHrPoma, carcinoid syndrome, calcitoninoma, GHRHoma and somatostatinoma. The recommendations provided in this paper focus on the biochemical, genetic and imaging work-up as well as therapeutic management of the individual hormonal syndromes in well-differentiated, grade 1-3, functioning NET with the primary tumour originating in the pancreas, and for specific subtypes also in the duodenum.

A clinical analysis on functioning pancreatic neuroendocrine tumors (focusing on VIPomas): a single-center experience

VIPomas are generally rare functioning pancreatic neuroendocrine tumors (PanNETs) that cause watery diarrhea, hypokalemia, and achlorhydria. Due to their extreme rarity, the clinicopathological features and outcomes of VIPomas have not been well reported. This study aimed to determine the diagnostic and therapeutic characteristics and prognosis of VIPomas and to compare them with other PanNETs at a Japanese reference hospital. Medical records of 293 patients with PanNETs were collected. Patient and tumor characteristics and outcomes were retrospectively reviewed. This cohort had only 1.4% (four patients) of patients with VIPomas, and three of these patients changed from non-functioning (NF-) PanNETs during their disease course. Recurrences of hormonal symptoms were observed in all patients despite the initial controls, and all of them died from their disease, more specifically mainly from hormonal symptoms. Compared to the other PanNETs, VIPomas were all located at the pancreatic tail, were larger, and had a higher Ki-67 index and more metastasis. The median survival time was significantly shorter for patients with VIPoma than for those with NF-PanNET (5.9 vs. 26.7 years, p < 0.0001), insulinoma (21.8 years, p < 0.0001), and gastrinoma (12.3 years, p = 0.0325). This study presents the possibility of shifting from non-symptomatic to symptomatic VIPomas as they grow or of transforming from NF-PanNETs to VIPomas. VIPomas should be considered in patients with relatively large NF-PanNETs, especially those located in the pancreatic tail, when diarrhea is continuously observed. As hormonal symptoms are an important cause of death in VIPomas, long-term symptomatic control, which is relatively difficult, is of great significance.

Treatment options of metastatic and nonmetastatic VIPoma: a review

PURPOSE

VIPoma belongs to the group of neuroendocrine neoplasms. These tumours are located mostly in the pancreas and produce high levels of vasoactive intestinal peptide (VIP). In most cases, a metastatic state has already been reached at the initial diagnosis, with high levels of VIP leading to a wide spectrum of presenting symptoms. These symptoms include intense diarrhoea and subsequent hypopotassaemia but also cardiac complications, with life-threatening consequences. Treatment options include symptomatic therapy, systemic chemotherapy and targeted therapy, as well as radiation and surgery. Due to the low incidence of VIPoma, there are no prospective studies or evidence-based therapeutic standards to date.

METHODS

To evaluate the possible impact of different therapy strategies, we performed literature research using PubMed.

RESULTS

All possible treatment modalities for VIPoma have at least one of two therapy goals: antisecretory effects (symptom control) and antitumoural effects (tumour burden reduction). Symptomatic therapy is the most important in the emergency setting to rehydrate, balance electrolytes and stabilise the patient. Symptomatic therapy is also of great importance perioperatively. Somatostatin analogues play a major role in symptom control, although their efficiency is often limited. Chemotherapy may be effective in reaching stable disease for a certain time period, although its impact on symptom control is limited and often delayed. Among targeted therapy options, the usage of sunitinib appears to be the most effective in terms of symptom control and showing antitumoural effects at the same time. Experience with radiation is still limited; however, local ablative procedures seem to be promising options. Peptide receptor radiotherapy (PRRT) with radiolabelled somatostatin analogues (SSAs, 177Lu-DOTATATE) offers a targeted approach, especially in patients with high somatostatin receptor density. Surgery is the first-line therapy for nonmetastatic VIPoma. Additionally, if the resection of all visible tumour lesions is possible, the surgical approach seems preferable to other strategies in highly symptomatic patients. The role of surgery in very advanced stages where only tumour debulking is possible remains debatable. However, a high rate of immediate symptom control can be achieved by tumour debulking followed by somatostatin therapy, although the impact on survival remains unclear.

CONCLUSION

Surgery is the only curative option for nonmetastatic VIPoma. Additionally, surgery should be a first-line therapy option for highly symptomatic patients, especially if the resection of all tumour lesions (primary tumour and metastasis) is achievable. In frail patients, other modalities can be used.

Vasoactive intestinal peptide secreting tumour: An overview

Vasoactive intestinal peptide (VIP) secreting tumour (VIPoma) is a rare functional neuroendocrine tumour that typically arises from pancreatic islet cells. These present as sporadic, solitary pancreatic neoplasias with an estimated incidence of one in ten million individuals per year. Only around 5% of VIPomas are associated with multiple endocrine neoplasia type I syndrome. Excessive VIP secretion produces a clinical syndrome characterized by refractory watery diarrhoea, hypokalemia and metabolic acidosis. These coupled with elevated plasma levels of VIP are diagnostic. The majority of VIPomas are malignant and have already metastasized at the time of diagnosis (60%). Metastases occur most frequently in the liver, or regional lymph nodes, lungs, kidneys and bones. Some reports of skin metastases have been documented. Complete surgical resection continues to be the only potentially curative treatment. However, when the neoplasia cannot be excised completely, surgical debulking may provide palliative benefit. Other palliative options have included recently the peptide receptor radionuclide therapy which has shown to be effective and well-tolerated. This article will review all aspects of pancreatic VIPomas highlighting aspects such as clinical presentation, diagnosis and management.

Life-threatening diarrhea in neuroendocrine tumors: two case reports

Background

Neuroendocrine tumors are rare, heterogeneous neoplasms that produce a wide variety of clinical symptoms. Diarrhea in neuroendocrine tumors is incredibly common and is usually benign in nature. We report two extreme cases of diarrhea in metastatic neuroendocrine tumors that threatened fatality and provide evidence for steroids as a novel agent in the management of vasoactive intestinal peptide tumors.

Case presentation

A 63-year-old Caucasian male with a grade 2 (Ki-67 17%) metastatic small bowel neuroendocrine tumor, and a 43-year-old female with a grade 2 (Ki-67 5%) metastatic pancreatic vasoactive intestinal peptide tumor. Both patients suffered life-threatening diarrhea despite extensive treatment modalities, including new systemic agents. This case explains how a lack of compliance and patient under-reporting of symptoms contributed to their challenging clinical course. Only steroids had a significant sustained effect on the diarrhea of the patient with vasoactive intestinal peptide tumor.

Conclusions

This report discusses two rare cases of life-threatening diarrhea in neuroendocrine tumors and stresses the importance of accurate clinical history taking, patient education, and compliance for symptom control. The report suggests steroids as a potential novel pharmaceutical option in the management of vasoactive intestinal peptide tumors; this is of great significance as it may provide a new approach to their management and potentially act as a life-saving agent in other oncology patients.

Evaluation of the Octreotide Acetate Pen Injector and its Instructions for Use in a Formative Human Factors Study

Introduction

Octreotide acetate subcutaneous injection is indicated to treat acromegaly and the symptoms of carcinoid tumors and vasoactive intestinal peptide tumors (VIPomas). This formative human factors study assessed the octreotide acetate pen injector and accompanying instructions for use (IFU) with self-trained participants.

Methods

The study enrolled patients with diagnoses of acromegaly, carcinoid tumors, or VIPomas and healthcare practitioners (HCPs) who treat patients with these diagnoses. The IFU provided a stepwise process with illustrations to train participants on using the pen injector. Participants familiarized themselves with the pen injector and the IFU before administering 2 unaided injections into skin-like pads; administering the full dose into the pad was considered a successful injection. The investigators evaluated each injection by performance measures—specific tasks necessary to safely and correctly administer the medication—and subjective measures, which included participant comments, feedback from questions, and suggestions for improvements.

Results

The study enrolled 11 participants—8 patients and 3 HCPs. Participants had a success rate of 100% for both injections. Errors included 1 participant priming the pen with the incorrect dose and 2 participants not holding the injector button for 10 s after the injection. Neither error led to a failed injection. To improve the IFU, participants suggested changing the order of wording on the priming step, clarifying illustrations of the plunger, and stronger indications to hold the injector button.

Conclusion

The octreotide pen injector and IFU were usable by self-trained participants. Participant errors and suggestions provided a foundation for recommendations to improve the IFU.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01739-1.

Percutaneous Cryoablation of Recurrent Pancreatic Mass for Life-Threatening Pancreatic VIPoma Syndrome: A Case Report

We present the case of a 73-year-old female who underwent percutaneous cryoablation for recurrent life-threatening pancreatic vasoactive intestinal polypeptide-producing tumor (VIPoma) following a pancreaticoduodenectomy and chemotherapy 5 years earlier. She presented with profuse watery diarrhea causing severe electrolyte and acid-base abnormalities, along with acute kidney injury. Cryoablation was successful in treating her profound symptoms, completely reversing her clinical course. The patient has made a successful recovery for the last 1.5 years since the procedure.

Vasoactive intestinal peptide-oma causing refractory diarrhea in a young woman

Vasoactive intestinal peptide (VIP)-secreting neuroendocrine tumors are an exceptionally rare cause of chronic diarrhea. We describe a 36-year-old woman presenting with a 2-year history of severe diarrhea and electrolyte derangements ultimately diagnosed with VIPoma.

Perioperative Hypotensive Crisis in an Adolescent with a Pancreatic VIPoma and MEN1-Gene Variant

BACKGROUND

Vasoactive intestinal peptide-secreting tumours (VIPomas) lead to high-volume secretory diarrhoea with hypokalaemia, as well as hyperglycaemia and hypercalcaemia. Diagnosis is often delayed.

CASE DESCRIPTION

We present a 13-year-old girl with a distal pancreatic VIPoma diagnosed on her second hospital presentation who became severely hypotensive on anaesthetic induction prior to tumour removal, likely due to the vasodilatory effect of supraphysiological VIP levels. Prior to the second surgical attempt, an octreotide infusion was started preoperatively to suppress systemic VIP levels and counter the potential for VIP-induced hypotension upon tumour manipulation, and the tumour was successfully resected. Hyperparathyroidism and history of GI tumour resection were subsequently identified in the father, and the two members were found to have a heterozygous variant of uncertain significance in the multiple endocrine neoplasia type 1 (MEN1) gene. However, as this family meets the diagnostic criteria for MEN1 clinically, ongoing surveillance for MEN1 tumours and genetic counseling for at-risk family members are required despite the non-pathogenic genetic result.

CONCLUSION

This case highlights the importance of screening for a VIPoma in patients with high-volume secretory diarrhoea and preventing cardiovascular complications with perioperative VIP suppression. Furthermore, careful interpretation of genetic results within the clinical context is required.

Chronic Diarrhea Secondary to Newly Diagnosed VIPoma

Vasoactive intestinal polypeptide-secreting tumors (VIPoma) are a rare pancreatic neuroendocrine tumor that can cause chronic diarrhea with 1 case per 10 million people per year. Diagnosis is made based on a combination of laboratory evaluation (serum VIP level), imaging findings (functional positron emission tomography-computed tomography [PET-CT]), and histological analysis (chromogranin A stain). We present a case of a male with 6 months of diarrhea and malaise who was found to have significant kidney injury and hypokalemia requiring admission to the medical intensive care unit. Subsequent laboratory evaluation while admitted eventually showed a low stool osmotic gap (–11 mOsm/kg) consistent with secretory diarrhea, in addition to significantly elevated VIP levels at 940 pg/mL (normal <75). Cross-sectional imaging with functional Gallium-68 dotatate PET-CT confirmed metastatic functional neuroendocrine tumor indicative of a VIPoma. Pathology on subsequent metastatic liver lesion aspiration was consistent with a well-differentiated VIPoma, and symptoms dramatically improved following initiation of octreotide therapy.

Pancreatic VIPomas from China: Case reports and literature review

Vasoactive intestinal polypeptide-secreting tumors (VIPomas) are rare neuroendocrine tumors that often present as watery diarrhea, hypokalemia, and achlorhydria or hypochlorhydria. In this study, we present our institutional experience of diagnosis and treatment of VIPomas, along with a review of the Chinese literature since 1980. Patient #1, diagnosed in 1984 and with intact clinical records, shows the natural history of this disease. Patient #2, diagnosed in 2015, shows the results of evaluation by nuclear medicine techniques and the outcomes of standardized treatment. Comprehensive review of 41 cases allows evaluation of clinical characteristics, treatments and outcomes of pancreatic VIPoma patients. All patients presented with watery diarrhea. The average stool volume reached 3247 mL per day. Average serum VIP level was 839.3 ng/L. Twelve of the 41 cases were reported to have metastases at diagnosis. Somatostatin receptor scintigraphy and ¹⁸FDG PET-CT are efficient methods for detection of VIPoma. Surgical excision can promptly alleviate hormonal symptoms.

The impact of failure to achieve symptom control after resection of functional neuroendocrine tumors: An 8-institution study from the US Neuroendocrine Tumor Study Group

BACKGROUND

The goals of resection of functional neuroendocrine tumors (NETs) are two-fold: Oncological benefit and symptom control. The interaction between the two is not well understood.

METHODS

All patients with functional NETs of the pancreas, duodenum, and ampulla who underwent curative-intent resection between 2000 and 2016 were identified. Using Cox regression analysis, factors associated with reduced recurrence-free survival (RFS) were identified.

RESULTS

Two-hundred and thirty patients underwent curative-intent resection. Fifty-three percent were insulinomas, 35% gastrinomas, and 12% were other types. Twenty-one percent had a known genetic syndrome, 23% had lymph node (LN) positivity, 80% underwent an R0 resection, and 14% had no postoperative symptom improvement (SI). Factors associated with reduced RFS included noninsulinoma histology, the presence of a known genetic syndrome, LN positivity, R1 margin, and lack of SI. On multivariable analysis, only the failure to achieve SI following resection was associated with reduced RFS. Considering only those patients with an R0 resection, failure to achieve SI was associated with worse 3-year RFS compared with patients having SI (36% vs 80%; P = 0.006).

CONCLUSIONS

Failure to achieve symptomatic improvement after resection of functional NETs is associated with worse RFS. These patients may benefit from short-interval surveillance imaging postoperatively to assess for earlier radiographical disease recurrence.

Ventricular fibrillation resulting from electrolyte imbalance reveals vipoma in MEN1 syndrome

Sporadic VIPoma is an exceedingly rare tumor with an annual incidence of 1:10 million people worldwide, yet it is described in approximately 5 % of MEN1 patients. The majority of VIPomas are malignant and radical surgery is the best therapeutic option. A 58-year-old man presented with cardiocirculatory arrest due to ventricular fibrillation. The patient had a 3-month history of epigastric pain with diarrhea. After reanimation, laboratory data revealed severe hypokalemia and hypercalcemia. Further investigations showed hyperparathyroidism, left adrenal adenoma and pituitary microprolactinoma and genetic diagnosis of MEN1 syndrome was made. Abdominal computed tomography revealed a 45 × 30 mm mass of the pancreatic head and two hepatic lesions, which proved to be neuroendocrine after 68 Ga PET and needle biopsy. Vasoactive intestinal peptide (VIP) serum level had increased. Subsequently the patient underwent pylorus-preserving pancreaticoduodenectomy and hepatic resection. Intraoperative VIP returned to normal values. Histopathology confirmed a pancreatic VIPoma metastatic to the liver. The postoperative course was unremarkable and the patient is well with no evidence of disease at a 48 months follow-up. Even in case of anusual presentation, when two or more main clinical findings of MEN1 related tumors are present, unrespectively to the presence of MEN1 mutation, MEN1 syndrome should be suspected. Surgery in MEN1 pancreatic neuroendocrine tumors is indicated both to treat symptoms and to avoid oncological progression even in advanced cases.

Medical management of secretory syndromes related to gastroenteropancreatic neuroendocrine tumours

Although recent epidemiological evidence indicates that the prevalence of non-functioning gastroenteropancreatic (GEP) neuroendocrine tumours (NETs) is rising, a significant number of GEP-NETs still present with symptoms related to the secretion of biologically active substances leading to the development of distinct clinical syndromes. In the past, these syndromes were associated with substantial morbidity and mortality due to the lack of specific therapies; however, since the introduction of long-acting somatostatin analogues and medications such as proton pump inhibitors, their control has been greatly improved. As a result, nowadays, the main cause of morbidity and mortality in GEP-NETs is mostly directly related to tumour growth and the extent of metastatic disease. However, in some patients with functioning tumours and extensive disease, control of the secretory syndrome still remains problematic, necessitating the employment of several cytoreductive techniques, which may not always be sufficient. Recently, new agents directed against tumour growth, or exerting increased binding activity to receptors expressed in these tumours, or interfering with the synthetic pathway of some of the compounds secreted by these tumours, have been developed. Since there are no specific guidelines addressing the totality of the management of the secretory syndromes related to GEP-NETs, this review aims at critically analysing the medical management of previously recognised secretory syndromes; it also addresses areas of uncertainty, assesses the newer therapeutic developments and also addresses recently described but poorly characterised secretory syndromes related to GEP-NETs.

Pancreatic neuroendocrine tumors: contemporary diagnosis and management

Pancreatic neuroendocrine tumors (PNETs) are neoplasms that arise from the hormone producing cells of the islets of Langerhans, also known as pancreatic islet cells. PNETs are considered a subgroup of neuroendocrine tumors, and have unique biology, natural history and clinical management. These tumors are classified as 'functional' or 'non-functional' depending on whether they release peptide hormones that produce specific hormone- related symptoms, usually in established patterns based on tumor subtype. This manuscript will review pancreatic neuroendocrine tumor subtypes, syndromes, diagnosis, and clinical management.

Emergency therapy for liver metastases from advanced VIPoma: surgery or transarterial chemoembolization?

VIPoma is a rare neuroendocrine tumor (NET) with a high potential to develop hepatic metastases and poor prognosis. The primitive tumor is nonsymptomatic and usually localized within the pancreas. Liver metastasis drives the prognosis and induces profuse watery diarrhea or renal failure. We herein present severe renal failure or diarrhea in two patients hospitalized in intensive care justifying emergency treatment of liver metastasis. The two patients experienced severe diarrhea due to a hypersecretion of vasoactive intestinal peptide (VIP) from liver metastasis released into the blood circulation. Therapeutic management was discussed and liver transarterial chemoembolization (TACE) was performed with chemotherapy-loaded embospheres, which cause necrosis of tumor lesions. TACE controlled the hormonal syndrome and made patients eligible for curative surgery. Tumor necrosis occurred and VIP levels collapsed. Surgery was performed in one of the two cases after TACE and the patient was considered in remission. Both patients were still alive after 3 years of follow up. Thus, TACE is feasible and appears to be an effective emergency treatment in patients with a VIP-hormonal syndrome due to liver metastases. Despite the biological disorder due to the hormonal secretion, an aggressive approach is warranted in VIP liver metastasis.

Clinical Presentation and Diagnosis of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors are a rare group of neoplasms that arise from multipotent stem cells in the pancreatic ductal epithelium. Although they comprise only 1% to 2% of pancreatic neoplasms, their incidence is increasing. Most pancreatic neuroendocrine tumors are nonfunctioning, but they can secrete various hormones resulting in unique clinical syndromes. Clinicians must be aware of the diverse manifestations of this disease, as the key step to management of these rare tumors is to first suspect the diagnosis.

A short history of neuroendocrine tumours and their peptide hormones

The discovery of neuroendocrine tumours of the gastrointestinal tract and pancreas started in 1870, when Rudolf Heidenhain discovered the neuroendocrine cells, which can lead to the development of these tumours. Siegfried Oberndorfer was the first to introduce the term carcinoid in 1907. The pancreatic islet cells were first described in 1869 by Paul Langerhans. In 1924, Seale Harris was the first to describe endogenous hyperinsulinism/insulinoma. In 1942 William Becker and colleagues were the first to describe the glucagonoma syndrome. The first description of gastrinoma by Robert Zollinger and Edwin Ellison dates from 1955. The first description of the VIPoma syndrome by John Verner and Ashton Morrison dates from 1958. In 1977, the groups of Lars-Inge Larsson and Jens Rehfeld, and of Om Ganda reported the first cases of somatostatinoma. But only in 2013, Jens Rehfeld and colleagues described the CCK-oma syndrome. The most recently updated WHO classification for gastrointestinal neuroendocrine tumours dates from 2010.

Metastatic VIPoma presenting as an ovarian mass

INTRODUCTION

Pancreatic VIPomas are exceedingly rare, with an annual incidence of less than 1 per million. Most VIPomas are metastatic at diagnosis, with the liver being the most common site of spread.

PRESENTATION OF CASE

We describe a highly unusual case of a metastatic pancreatic VIPoma to an ovary in a 54 year-old patient. She was ten years out from her initial diagnosis when routine CT scan showed an enlarging left adnexal mass. After having both ovaries removed laparoscopically the final pathology was consistent with her pancreatic primary. To our knowledge, there has been only one other such case described in the literature.

DISCUSSION

In this case, pathology revealed metastatic neuroendocrine tumor involving both the left and right ovaries despite only the right ovary apparently enlarging. In our literature search, only two other cases of metastatic PNET to the ovaries have been reported. One case was a glucagonoma and the other a VIPoma. We recommend that clinicians consider referral of patients with metastatic NET and ovarian metastases to gynecologic surgery for consideration of surgical resection.

CONCLUSION

In conclusion, this case proves that although uncommon, PNET can show metastases in both ovaries even a decade after initial diagnosis.

Sporadic pancreatic vasoactive intestinal peptide-producing tumor (VIPoma) in a 47-year-old male

VIPoma is an exceedingly unusual neuroendocrine neoplasm that autonomously secretes vasoactive intestinal polypeptide (VIP). Its reported incidence is approximately 1 per 10 million individuals per year. Herein, we report the case of sporadic pancreatic VIPoma in a 47-year-old male who presented with a six-month history of chronic, plentiful, watery diarrhea. On physical examination, the patient looked sick, lethargic and had signs of dehydration. Laboratory investigations revealed high VIP hormone level (989pg/mL), hypokalemia, hypercalcemia, hyperglycemia, high blood urea nitrogen, high creatinine, and metabolic acidosis on arterial blood gas. Contrast-enhanced computed tomography (CT) scan showed a 3.1×3.3×4.7cm, well-defined, enhancing lesion involving the pancreatic tail with a cystic component. Moreover, a 5.7×6.1×6.8cm metastatic hepatic lesion was identified. The patient underwent distal pancreatectomy with splenectomy, hepatic lesion resection, and lymph node dissection. Histopathological and immunohistochemical examination of the pancreatic and hepatic lesions revealed neuroendocrine tumor (VIPoma). Postoperatively, the patient received radiofrequency ablation for the hepatic lesion. A post-operative six-month follow-up showed significant symptomatic relief, reduced VIP hormone level (71pg/mL) and normalized electrolyte and acid-base profiles. However, a magnetic resonance imaging (MRI) scan showed a small residual metastatic liver lesion which was considered for hepatic artery embolization (HAE). The patient is still alive with a residual hepatic disease at 18months. We also present a brief literature review on VIPoma.

Ischemic stroke as a presenting feature of VIPoma due to MEN 1 syndrome

INTRODUCTION

Presentation of the ischemic stroke due to vasoactive intestinal peptide producing tumor (VIPoma) or Verner Morrison syndrome is rare. This is first of its kind case which we are reporting here which was later turned out to be multiple endocrine neoplasia type 1 (MEN 1) syndrome with diagnosis of primary hyperparathyroidism in the same patient in follow-up.

DESCRIPTION OF THE CASE

A 13-year-old girl presented to our emergency department with features of disorientation, weakness of left sided extremities. She had watery high volume diarrhea and related dehydration with renal failure. Blood chemistry was suggestive of hypokalemia with metabolic acidosis. Patient had flushing on her face during this episode of illness. Magnetic resonance imaging (MRI) of brain suggested venous infarct. Computed tomography (CT) scan of abdomen done with high index of suspicion was suggestive of mass in tail of pancreas mostly a VIPoma. Patient was operated for the tumor after which there was no recurrence of diarrhea. Biopsy of tumor was consistent with VIPoma with chomogranin A positivity. Patient improved of her stroke episode with time. On follow-up she is diagnosed to have primary hyperparathyroidism with hypercalcemia due to left inferior parathyroid adenoma which improved with intravenous (IV) zolindronic acid therapy and now she is planned to undergo parathyroidectomy.

CONCLUSION

VIPoma is a rare tumor but is well-described with MEN 1. Stroke as a presenting feature of VIPoma is first reported with this case.

Pancreatic vasoactive intestinal polypeptide-secreting tumor: A case reporty

Vasoactive intestinal polypeptide-secreting tumor (VIPoma) of the pancreas is a rare type of pancreatic endocrine neoplasm. The main clinical features of VIPoma include large amount of watery diarrhea, hypokalemia and achlorhydria. Due to extreme rarity of this disease, it is easily misdiagnosed. Here we report such a case to raise the awareness of this clinical entity. We also performed a review of the literature to summarize its clinical manifestations, diagnosis and treatment.

VIPoma Crisis: Immediate and life saving reduction of massive stool volumes on starting treatment with octreotide

We report the case of a 57-year-old male physician who presented with a life threatening secretory and refractory diarrhoea of around 20 L/day. This was complicated by severe hypotension, hypokalaemia, hypercalcaemia, renal failure requiring dialysis, metabolic acidosis, cardiorespiratory arrest and ventilation for 12 days. His diarrhoea responded immediately to the first dose of a therapeutic trial of subcutaneous octreotide 100 mcg 8 hourly which was started on clinical grounds alone before any investigations were carried out. After one day he was extubated and his blood pressure returned to normal. When a functioning neuroendocrine tumour is suspected clinically, the use of octreotide can, as in this case, be life saving.

Multimodal imaging in functional endocrine pancreatic tumors

Endocrine pancreatic tumors, also known as pancreatic islet tumors, are rare entities of neuroendocrine origin that are located within the pancreas or in its close proximity. Approximately 50% of these tumors secrete biologically active substances that lead to the development of specific clinical syndromes. Once diagnosis has been established on the basis of clinical and laboratory findings, localization of the source of pathologic hormone secretion is warranted. Endocrine pancreatic tumor imaging comprises anatomical imaging modalities, such as ultrasound, computed tomography (CT) and MRI, as well as functional radiological studies, including arterial calcium stimulation with hepatic venous sampling, and functional nuclear medicine imaging modalities, such as scintigraphy and PET. The recent combination of high-resolution anatomic studies and functional imaging, such as PET/CT and single-photon emission CT/CT, allows excellent diagnostic evaluation of pancreatic islet cell tumors and has, therefore, especially high value. Given that none of these imaging methods are exclusively superior to the others, visualization of pancreatic islet cell tumors often requires the combination of different imaging modalities.

Amelioration of symptoms and reduction of VIP levels after hepatic artery chemoembolization in a patient with sandostatin resistant VIPoma

Vasoactive intestinal polypeptide secreting islet cell tumors (VIPomas) are neuroendocrine tumors that secrete excessive amounts of vasoactive intestinal polypeptide (VIP) that cause distinct syndromes characterized by large-volume diarrhea, hypokalemia, and dehydration. The annual incidence of these tumors is estimated to be about one per 10,000,000 individuals in the general population. We report a successful treatment of VIPoma with hepatic chemoembolization of a metastatic hepatic lesion evidenced by a reduction of VIP levels and resolutions of symptoms in a patient with pancreatic VIPoma unresponsive to increased doses of an octreotide analog.