Surgical treatment of sporadic gastrinoma

Determinants of surgical resection for pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (pNETs) include functioning and non-functional tumors. Functioning tumors consist of tumors that produce a variety of hormones and their clinical effects. Therefore, determinants of resection of pNETs should be discussed for each group of tumors. Less than 10% of insulinomas are malignant, therefore more than 90% of the cases can be cured by surgical resection. Lymphadenectomy is generally not necessary in insulinoma operation. If preoperative localization of the insulinoma is completed, enucleation from the pancreatic body or tail, and distal pancreatectomy can be performed safely by laparoscopy. When preoperative localization of a sporadic insulinoma is not confirmed, surgical exploration is needed. Intraoperative localization of a tumor, intraoperative insulin sampling and frozen section are required. The crucial purpose of surgical resection is to control inappropriate insulin secretion by removing all insulinomas. Gastrinomas are usually located in the duodenum or pancreas, which secrete gastrin and cause Zollinger-Ellison syndrome (ZES). Duodenal gastrinomas are usually small, therefore they are not seen on preoperative imaging studies or endoscopic ultrasound, and can be found only at surgery if a duodenotomy is performed. In addition, lymph node metastasis is found in 40-60% of cases. Therefore, the experienced surgeons should direct operation for gastrinomas. Surgical exploration with duodenotomy should be performed at a laparotomy. Other functioning pNETs can occur in the pancreas or in other locations. Curative resection is always recommended whenever possible after optimal symptomatic control of the clinical syndrome by medical treatment. Indications for surgery depend on clinical symptom control, tumor size, location, extent, malignancy and presence of metastasis. A lot of non-functioning pNETs are found incidentally according to the quality improvement of imaging techniques. Localized, small, malignant non-functioning pNETs should be operated on aggressively, while in possibly benign tumors smaller than 2 cm the surgical risk-benefit ratio should be carefully weighted. Surgical liver resection is generally proposed in curative intent to all patients with operable metastases from G1 or G2 pNET. The benefits of surgical resection of liver metastases have been demonstrated in terms of overall survival and quality of life. Complete resection is associated with better long-term survival.

Lymph nodes metastasis and recurrences justify an aggressive treatment of gastrinoma

In the current study, short- and long-term outcomes after aggressive surgical treatment for gastrinoma were evaluated. From August 1990 to August 2009, 20 patients diagnosed with Zollinger Ellison syndrome were reviewed. Eleven pancreaticoduodenectomies, three total pancreatectomies, four lymph node dissections, four enucleations and two palliative procedures were performed. Four (27.8 %) patients had disease associated with MEN1 syndrome, 13 (72.2 %) had sporadic gastrinomas (SG) and 3 had disease of unknown primary origin. No in-hospital mortality was observed. After radical resection, lymph node metastasis was present in 82 % of the cases. Eight percent of patients who underwent radical resection developed recurrence compared with 100 % of those who underwent enucleoresection (p = 0.03). Average time to recurrence in patients with sporadic gastrinoma was 66.7 months (confidence interval (CI) 62.9-70.5) in those treated with enucloeresection compared to 181.1 months (CI 124.3-237.8) in the radical resection group (p = 0.007). One recurrence was observed in the MEN1 group. Based on post-operative mortality, recurrence and lymph node metastasis, our data suggest that patients with gastrinoma should undergo abdominal exploration with aggressive resection of the primary tumour and regional lymph nodes in place of conservative treatment.

Gastric acid hypersecretory states: recent insights and advances

Gastric acid hypersecretory states are characterized by basal hypersecretion of gastric acid and historically include disorders associated with hypergastrinemia, hyperhistaminemia, and those of unknown etiology. Although gastric acid secretion is infrequently measured, it is important to recognize the role of gastric hypersecretion in the symptoms of these disorders because they share several features of pathogenesis and treatment. In this article, recent important articles reporting insights into their diagnosis, pathogenesis, and treatment are reviewed. Particular attention is paid to Zollinger-Ellison syndrome, because it has the most extreme acid hypersecretion of this group of disorders and because numerous recent articles deal with various aspects of the diagnosis, molecular pathogenesis, and treatment of the gastrinoma itself or the acid hypersecretion. Two new hypersecretory disorders are reviewed: rebound acid hypersecretion after the use of proton pump inhibitors and acid hypersecretion with cysteamine treatment in children with cystinosis.

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.

Reoperative surgery in sporadic Zollinger-Ellison Syndrome: longterm results

BACKGROUND

Most patients with Zollinger-Ellison Syndrome (ZES), even those in whom gastrinoma is found and resected at initial operation, will suffer from persistent or recurrent disease in longterm followup. There is currently no consensus about managing patients with recurrent or persistent ZES. Our unit has historically maintained an aggressive approach toward monitoring and reoperation for patients with sporadic ZES.

STUDY DESIGN

We performed a review of a consecutive series of patients evaluated and managed at our institution between 1970 and 2007 for ZES. "Biochemical cure" was defined as normal serum gastrin assays and negative imaging studies. Reoperations were performed for elevations in serum gastrin assays and positive findings on imaging studies.

RESULTS

Fifty-two patients with sporadic ZES were analyzed. Median followup was 14 years. Among patients with sporadic ZES, 37 patients underwent operative management. The most common operations were resection of duodenal gastrinoma (n=8) and total gastrectomy (n=7). Nine patients underwent 15 reoperations for recurrent or persistent disease. "Biochemical cure" was obtained in four patients (44%) undergoing reoperation for ZES. Three of these patients remained without evidence of recurrence at 4, 9, and 12 years after their curative re-resection. Only one of nine patients who underwent reoperation died of metastatic gastrinoma.

CONCLUSIONS

Primary and reoperative surgery in patients with sporadic ZES results in a significant rate of "biochemical cure." In selected patients with recurrent or persistent disease, reoperation for resection of gastrinoma is associated with excellent longterm survival and is warranted.