Gastrinoma and Zollinger Ellison syndrome:A roadmap for the management between new and old therapies

Zollinger-Ellison syndrome(ZES)associated with pancreatic or duodenal gastrinoma is characterized by gastric acid hypersecretion,which typically leads to gastroesophageal reflux disease,recurrent peptic ulcers,and chronic diarrhea.As symptoms of ZES are nonspecific and overlap with other gastrointestinal disorders,the diagnosis is often delayed with an average time between the onset of symptoms and final diagnosis longer than 5 years.The critical step for the diagnosis of ZES is represented by the initial clinical suspicion.Hypergastrinemia is the hallmark of ZES;however,hypergastrinemia might recognize several causes,which should be ruled out in order to make a final diagnosis.Gastrin levels>1000 pg/mL and a gastric pH below 2 are considered to be diagnostic for gastrinoma;some specific tests,including esophageal pH-recording and secretin test,might be useful in selected cases,although they are not widely available.Endoscopic ultrasound is very useful for the diagnosis and the local staging of the primary tumor in patients with ZES,particularly in the setting of multiple endocrine neoplasia type 1.Some controversies about the management of these tumors also exist.For the localized stage,the combination of proton pump inhibitory therapy,which usually resolves symptoms,and surgery,whenever feasible,with curative intent represents the hallmark of gastrinoma treatment.The high expression of somatostatin receptors in gastrinomas makes them highly responsive to somatostatin analogs,supporting their use as anti-proliferative agents in patients not amenable to surgical cure.Other medical options for advanced disease are super-imposable to other neuroendocrine neoplasms,and studies specifically focused on gastrinomas only are scant and often limited to case reports or small retrospective series.The multidisciplinary approach remains the cornerstone for the proper management of this composite disease.Herein,we reviewed available literature about gastrinoma-associated ZES with a specific focus on differential diagnosis,providing potential diagnostic and therapeutic algorithms.

One size does not fit all for pancreatic cancers: A review on rare histologies and therapeutic approaches

Exocrine pancreatic neoplasms represent up to 95%of pancreatic cancers(PCs)and are widely recognized among the most lethal solid cancers,with a very poor 5-year survival rate of 5%-10%.The remaining<5%of PCs are neuroendocrine tumors that are usually characterized by a better prognosis,with a median overall survival of 3.6 years.The most common type of PC is pancreatic ductal adenocarcinoma(PDAC),which accounts for roughly 85%of all exocrine PCs.However up to 10%of exocrine PCs have rare histotypes,which are still poorly understood.These subtypes can be distinguished from PDAC in terms of pathology,imaging,clinical presentation and prognosis.Additionally,due to their rarity,any knowledge regarding these specific histotypes is mostly based on case reports and a small series of retrospective analyses.Therefore,treatment strategies are generally deduced from those used for PDAC,even if these patients are often excluded or not clearly represented in clinical trials for PDAC.For these reasons,it is essential to collect as much information as possible on the management of PC,as assimilating it with PDAC may lead to the potential mistreatment of these patients.Here,we report the most significant literature regarding the epidemiology,typical presentation,possible treatment strategies,and prognosis of the most relevant histotypes among rare PCs.