Hypervascular pancreatic "lesions": a pattern-based approach to differentiation

Hypervascular pancreatic lesions/masses can arise due to a variety of causes, both benign and malignant, leading to a wide differential diagnosis. Accurate differentiation of these lesions into appropriate diagnoses can be challenging; however, this is important for directing clinical management. This manuscript provides a multimodality imaging review of hypervascular pancreatic lesion, with emphasis on an imaging-based algorithmic approach for differentiation of these lesions, which may serve as a decision support tool when encountering these uncommon lesions. Additionally, we stratify these lesions into three categories based on malignant potential, to help guide clinical management.

Treatment of symptomatic neuroendocrine tumor syndromes: recent advances and controversies

INTRODUCTION

Neuroendocrine tumors(NETs), once thought rare, are increasing in frequency in most countries and receiving increasing-attention. NETs present two-treatment problems. A proportion is aggressive and a proportion has a functional, hormone-excess-state(F-NET), each of which must be treated. Recently, there have been many advances, well-covered in reviews/consensus papers on imaging-NETs; new, novel anti-tumor treatments and understanding their pathogenesis. However, little attention has been paid to advances in the treatment of the hormone-excess-state. These advances are usually reported in case-series, and case-reports with few large studies. In this paper these advances are reviewed. Areas covered: Advances in the last 5-years are concentrated on, but a review of literature from the last 10-years was performed. PubMed and other databases (Cochrane, etc.) were searched for F-NET-syndromes including carcinoid-syndrome, as well as meeting-abstracts on NETs. All advances that controlled hormone-excess-states or facilitated-control were covered. These include new medical-therapies [serotonin-synthesis inhibitors(telotristat), Pasireotide, new agents for treating ACTHomas], increased dosing with conventional therapies (octreotide-LAR, Lanreotide-Autogel), mTor inhibitors(everolimus), Tyrosine-kinase inhibitors(sunitinib),cytoreductive surgery, liver-directed therapies (embolization, chemoembolization, radioembolization, RFA), peptide radio-receptor-therapy(PRRT) and ¹³¹I-MIBG, ablation of primary F-NETs. Expert opinion: Although many of the newer therapies controlling the hormone-excess-states in F-NETs are reported in relatively few patients, all the approaches show promise. Their description also generates some controversies/unresolved areas,such as the order of these new treatments, their longterm-efficacy, and effectiveness of combinations which may require large,controlled studies.

The Zollinger-Ellison syndrome: dangers and consequences of interrupting antisecretory treatment

BACKGROUND & AIMS

Patients with Zollinger-Ellison syndrome (ZES) are treated by proton pump inhibitors (PPIs) to protect them from severe and potentially lethal peptic complications related to massive gastric acid hypersecretion. We report here on the dangerous consequences of interrupting PPI therapy.

METHODS

We describe 2 ZES patients in whom interruption of PPI treatment for diagnostic evaluation generated severe health complications.

RESULTS

Less than 48 hours after stopping PPIs, patient 1 developed multiple strictures of the esophagus caused by massive vomiting of gastric acid, and patient 2 presented with severe abdominal pain with intestinal microperforation from duodenal ulcers. Because of persistent gastrin stimulatory drive and because of the abolition of reflex protective defense mechanisms against gastric acid hypersecretion during PPI treatment, patients with ZES under PPI therapy are exposed to severe peptic complications when facing rebound acid secretion at the interruption of their antisecretory treatment.

CONCLUSIONS

PPI treatment interruption has dangerous consequences, and PPI therapy always should be maintained in patients known or suspected of ZES. Diagnostic evaluations should be performed under PPI protection.

Reoperative surgery for the Zollinger-Ellison syndrome

It is clear that a properly performed initial operation is the key to success in the management of a patient with ZES. However, reoperation is frequently a consideration in the management of patients with ZES because high rates of persistent and recurrent disease are manifest even with modern imaging and surgical approaches. In carefully selected patients, reoperation can result in durable biochemical cure and improved survival and should be considered. A thorough knowledge of the natural history of the sporadic form of ZES and ZES in the context of MEN-1, patterns of presentation, and sites of metastases are necessary to achieve the best outcome in patients with this unusual disease.

Long-Term Results of a Selective Surgical Approach to Management of Zollinger-Ellison Syndrome in Patients with MEN-1

The role of operation in patients with Multiple Endocrine Neoplasia Type 1 (MEN-1) and Zollinger-Ellison Syndrome (ZES) is controversial. Our institutional bias for this disease has, in general, been towards aggressive imaging and operative removal of localized gastrinomas. Few studies have reported long-term outcomes in patients with MEN-1 and ZES. A single institution retrospective review of all patients with MEN-1 and ZES from 1970 to present was performed. Twelve patients were identified (median age = 37 years at diagnosis). The median follow-up was 18 years from diagnosis of ZES. Common symptoms associated with gastrinoma in these patients were diarrhea (n = 6), abdominal pain (n = 4), and nausea/vomiting (n = 4). Most commonly identified sites of gastrinoma were: pancreas (n = 10), duodenum (n = 4), lymph nodes (n = 3), and liver (n = 1). Fifteen celiotomies were performed in total (median = 1; range 0-3). Operative procedures performed included: distal pancreatectomy (n = 4), acid reducing procedure (n = 4), enucleation of pancreatic gastrinoma (n = 3), duodenal resection (n = 3), pancreaticoduodenectomy (n = 1), and other (n = 7). One patient had a transient biochemical cure after operation lasting 3 years. Only one patient in this series had documented liver metastases of gastrinoma and no patients expired of metastatic gastrinoma. There was one postoperative patient death, secondary to respiratory arrest thought to be a result of aspiration or pulmonary embolus. Three patients died of nondisease related causes, and seven patients were alive at the time of last follow-up. Operations rarely result in biochemical cures in patients with MEN-1 and ZES. In our experience, resection of localized gastrinomas often did not require extended surgical resection and were associated with excellent long-term outcomes.