Surgical management of malignant islet cell tumors

Impact of Regional Metastasis on Survival for Patients with Nonfunctional Pancreatic Neuroendocrine Tumors: A Systematic Review

BACKGROUND

Controversy exists regarding the benefit of lymphadenectomy for nonfunctional pancreatic neuroendocrine tumors (NF-PNET).

PATIENTS AND METHODS

MEDLINE/PubMed, EMBASE, and the Cochrane Library were searched for studies of pancreatic neuroendocrine tumors (PNET) published between 1990 and 2021. Studies of functional PNET were excluded. Reported incidence of lymph node metastasis (LNM) and survival analysis of either disease-free survival (DFS) or overall survival (OS) were required for inclusion.

RESULTS

Overall, 52 studies analyzing 24,608 PNET met the inclusion criteria. The reported LNM rate for NF-PNET ranged from 7 to 64 % (median 24.5%). Reported LNM rates ranged from 7 to 51% (median 11%) for NF-PNET< 2 cm in 14 studies and 29-47% (median 38%) in NF-PNET > 2 cm. In total, 19 studies (66%) reported LNM to have a negative impact on DFS. Additionally, 21 studies (60%) reported LNM to have a negative impact on OS. Two studies investigating the impact of lymphadenectomy (LND) found LND had the greatest impact for large, high-grade tumors. The overall quality of available evidence was low as assessed by the Grading of Recommendations, Assessment, Development, and Evaluation System.

CONCLUSIONS

Published literature evaluating the impact of regional LNM and LND in PNET is confounded by heterogeneity in practice patterns and the retrospective nature of these cohort studies. Most studies suggest high rates of LNM in NF-PNET that negatively impact DFS and OS. Given the high rate of LNM in NF-PNET and its potential detrimental effect on DFS and OS, we recommend lymphadenectomy be completed for NF-PNET > 2 cm and strongly considered for NF-PNET < 2 cm.

Assessment of tumor growth in pancreatic neuroendocrine tumors in von Hippel Lindau syndrome

BACKGROUND

The incidence of pancreatic neuroendocrine tumors (PNETs) is increasing, but only a subset of these heterogeneous tumors will progress to malignant disease, which is associated with a poor prognosis. Currently, there are limited data on the natural history of these tumors and it is difficult to determine which patients require surgical intervention because the risk of metastatic disease cannot be accurately determined.

STUDY DESIGN

We conducted a prospective study of 87 patients with von Hippel Lindau syndrome-associated solid pancreatic lesions to determine the natural history of these tumors with biochemical testing, follow-up anatomic and functional imaging, and advanced imaging analysis, with a median follow-up of 4 years.

RESULTS

Approximately 20% of consecutive tumor measurements during follow-up were decreased in size and 20% showed no change. This included 2 of 4 surgically proven malignant tumors, which had a net decrease in tumor size over time. Tumor volume, as derived from greatest diameter and volumetric measurements, showed good correlation to pathology tumor measurement of surgically resected tumors (Spearman rank correlation ρ = 0.72, p = 0.0011, and ρ = 0.83, p < 0.0001, respectively). Tumor density measurement had an inverse relationship with tumor size (Spearman rank correlation -0.22, p = 0.0047). A tumor density cutoff of 200 was 75% specific for malignant tumors.

CONCLUSIONS

Pancreatic neuroendocrine tumors demonstrate a nonlinear growth pattern, which includes periods of no growth and apparent decrease in size by imaging. These growth patterns are variable and are not associated with tumor grade and malignancy. Tumor density, as measured in this cohort, may offer a specific diagnostic tool for malignant disease.

Management of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors account for 1% to 2% of pancreatic neoplasms and may occur sporadically or as part of a hereditary syndrome. Patients may present with symptoms related to hormone secretion by functional tumors or to locally advanced or metastatic nonfunctional tumors. Asymptomatic pancreatic neuroendocrine tumors are increasingly detected incidentally during abdominal imaging performed for other reasons. The management of localized pancreatic neuroendocrine tumors is surgical resection. Hepatic metastases are common and their management involves a variety of liver-directed therapies, which should be tailored according to extent of disease, symptoms, presence of extrahepatic metastases, and patient performance status.

MSH2 and CXCR4 involvement in malignant VIPoma

BACKGROUND

Vasoactive intestinal polypeptide secreting tumors(VIPomas) are rare endocrine tumors of the pancreas with an estimated incidence of 0.1 per million per year. The molecular mechanisms that mediate development of VIPomas are poorly investigated and require definition.

METHODS

A genome- and gene expression analysis of specimens of a primary pancreatic VIPoma with hepatic metastases was performed. The primary tumor, the metastases, the corresponding healthy tissue of the liver, and the pancreas were compared with each other using oligonucleotide microarrays and loss of heterozygosity (LOH).

RESULTS

The results revealed multiple LOH events and several differentially expressed genes. Our finding of LOH and downregulation was conspicuous in the microarray analysis for the mismatch repair gene MSH2 in the primary pancreatic VIPoma tumor, the hepatic metastasis but not in the corresponding healthy tissue. Further a strong overexpression of the chemokine CXCR4 was detected in the hepatic metastases compared to its pancreatic primary. With a review of the literature we describe the molecular insights of metastatic development in VIPoma.

CONCLUSION

In VIPoma, defects in the mismatch repair system especially in MSH2 may contribute to carcinogenesis, and increased CXCR4 may be associated with liver metastasis.

Surgical treatment of sporadic pancreatic neuroendocrine tumors: a state of the art review

Pancreatic neuroendocrine tumors (PNETs) are rare neoplasms. They are clinically diverse and divided into functioning and nonfunctioning disease, depending on their ability to produce symptoms due to hormone production. Surgical resection is the only curative treatment and remains the cornerstone therapy for this patient group, even in patients with advanced disease. Over the last decade there has been a noticeable trend towards more aggressive surgery as well as more minimally invasive surgery in patients with PNETs. This has resulted in improved long-term survival in patients with locally advanced and metastatic disease treated aggressively, as well as shorter hospital stays and comparable long-term outcomes in patients with limited disease treated minimally invasively. There are still controversies related to issues of surgical treatment of PNETs, such as to what extent enucleation, lymph node sampling, and vascular reconstruction are beneficial for the oncologic outcome. Histopathologic tumor classification is of high clinical importance for treatment planning and prognostic evaluation of patients with PNETs. A constant challenge, which relates to the treatment of PNETs, is the lack of an internationally accepted histopathological classification system. This paper reviews current issues on the surgical treatment of sporadic PNETs with specific focus on surgical approaches and tumor classification.

Surgery in malignant pancreatic neuroendocrine tumors

BACKGROUND

Because of their rarity and indolent nature, optimal management of malignant pancreatic neuroendocrine tumors remains controversial. The purpose of this study is to review a series of patients with these tumors and investigate the role of surgery in the treatment.

METHODS

A retrospective study of 73 patients (ages 24-86 years; 36 women) undergoing treatment at a tertiary academic medical center was performed. Patient demographics, diagnostic tests, operations, pathologic findings, adjuvant treatments, and survival were reviewed.

RESULTS

Seventy-four percent of patients had advanced disease with hepatic metastases and 30% had functional tumors. Fifty-seven percent of the patients underwent pancreatic resections. Two 60-day mortalities occurred and the postoperative complication rate was 27%. Overall 5-year survival rate was 44%. There was no difference in survival between patients with functional and nonfunctional tumors. Patients undergoing resection, even in metastatic disease, had better survival than patients who had no resection (60% vs. 30%, P = 0.025). Recurrence occurred in 20% of patients who underwent a curative resection.

CONCLUSION

Patients with malignant pancreatic neuroendocrine tumors commonly present with advanced disease. Although, curative resection is not frequent, survival benefit may be obtainable with aggressive surgical management even in the face of metastatic disease.

Pancreatic neuroendocrine tumours

Pancreatic neuroendocrine tumours (PET) are rare neoplasms of the pancreas accounting for less than 5% of all primary pancreatic malignancies. Included in this group are insulinomas, gastrinomas, glucagonoma and somatostatinomas. Collectively these neoplasms are classified as functional PETs. Where a PET is not associated with a clinical syndrome due to hormone oversecretion, it is referred to as a non-functioning PET. Non-functioning PETs are pancreatic tumours with endocrine differentiation but lack a clinical syndrome of hormone hypersecretion. The incidence of these tumours varied between 15 and 53%. Presentation is related to the mass effect of the tumour with symptoms often non-specific. Treatment is surgical excision with chemotherapy and hormonal therapy is controversial. For functioning PETs, surgery remains the optimal therapy, however, long-term survival can be expected even in the presence of metastases. With advances in medical management, radiolabelled somatostatin therapy, hepatic arterial chemoembolisation and radiofrequency ablation, symptoms may be controlled to optimize quality of life.

Clinical endocrinology and metabolism. Gut endocrine tumours

Endocrine tumours of the gastrointestinal tract and pancreas may present at different disease stages with either hormonal or hormone-related symptoms/syndromes, or without hormonal symptoms. They may occur either sporadically or as part of hereditary syndromes. In the therapeutic approach to a patient with these tumours, excessive hormonal secretion and/or its effects should always be controlled first. A team approach is needed to achieve a balanced opinion on the use of the different therapeutic options in patients with these tumours.

Diagnosis and treatment of VIPoma in China: (case report and 31 cases review) diagnosis and treatment of VIPoma

OBJECTIVES

To discuss the experience of diagnosis and treatment of VIPoma by summarizing clinical information of 31 patients with VIPoma in China.

METHODS

To analyze clinical manifestations, laboratory examinations, imaging features, operation, pathologic findings, and follow-up survey of 31 patients, among them 1 case was from our hospital and the other 30 cases were reported in Chinese literature from 1977 to 2002.

RESULTS

Periodical backache, skin rash, and polyps of colon were never reported previously, all of which except polyps disappeared after operation. Partial resection of superior mesenteric vein was also never reported. The mean serum value of VIP which had been very high before operation, decreased markedly after the operation (963.2 pg/ml Versus 131.9 pg/ml),the immunohistochemical expression of many kinds of digestive hormone including VIP presented positive. Hepatic involvement was 29.0%,nodal metastasis was 9.7%.

CONCLUSIONS

VIPoma is rare. Typical symptoms and the serum value of VIP are keys to diagnosis before operation, Surgical resection is the most effective means for cure. surgical debulking of the tumor, somatostatin analogues can be used for good palliation.

Morphological and functional investigations of neuroendocrine tumors of the pancreas

Neuroendocrine tumors of the pancreas are rare neoplasms arising predominantly from the pancreatic islets of Langerhans and are thus known as islet cell tumors. More than the half of all neuroendocrine tumors are called functioning islet cell tumors because they secrete one or more biologically active peptides that may produce clinical symptoms. Clinical diagnosis of non-functioning, i.e., biologically inactive, tumors is often delayed and patients tend to present with advanced tumors (size greater than 5 cm) that are easily localized by using conventional imaging modalities. On the other hand, symptoms of functioning islet cell tumors usually appear early in the clinical course, rendering the preoperative localization of these small hormone-producing tumors (size less than 2 cm) difficult with non-invasive methods. Since functioning islet cell tumors can often be cured by surgical resection, invasive procedures are warranted when necessary for localization diagnosis. Failure to search for, detect, and resect these small tumors will invariably result in persistent symptoms. Regarding the unsatisfactory results of morphological imaging methods, functional studies, especially arterial stimulation with hepatic venous samplings, may provide a preoperative regionalization of the pancreatic adenoma, regardless of its size.

Surgical Experience with Functioning Pancreatic Neuroendocrine Tumors

Pancreatic islet-cell tumors (ICTs) are rare malignancies usually recognized by specific clinical endocrinopathies. The purpose of this study is to evaluate our surgical experience with functioning pancreatic ICT in an academic referral center. Twenty patients (male:female 12:8) with a mean age of 53 years (range 26–82) underwent surgery for a functioning pancreatic ICT [gastrinoma (eight), multiple endocrine neoplasia (three), insulinoma (seven), glucagonoma (four), and Vipoma (vasoactive intestinal peptide; one)] between June 1975 and March 2001. Signs and symptoms of hormonal excess were present in 95 per cent (19 of 20). One patient (glucagonoma) presented with obstructive jaundice and mild glucose intolerance. Elevated peptide levels were detected preoperatively in 65 per cent, including all patients with an insulinoma. Curative resections were attempted in 80 per cent including three procedures for insulinoma. Palliative procedures were performed in 20 per cent—all gastrinomas. One patient with an insulinoma had diffuse nesidioblastosis. Three patients (with gastrinoma, insulinoma, and glucagonoma) had lymph node-positive disease and three patients with gastrinoma had liver metastasis. The overall 30-day morbidity rate was 30 per cent and mortality rate 0 per cent. Symptomatic improvement was achieved in 90 per cent at a mean follow-up of 44 months. Two patients developed diabetes after a subtotal and a total pancreatectomy, respectively. Sixty-three per cent of patients who underwent an attempted curative resection are alive at a mean follow-up of 47 months (range 3–231) arid all patients who underwent a palliative procedure are alive at a mean follow-up of 31 months (range 27–36). Functioning pancreatic ICTs are fascinating tumors that produce distinct clinical syndromes. Symptomatic improvement is accomplished in the majority of patients after surgery and short-term palliation is achieved in patients with nohresectable disease.

A non-insulin secreting malignant insulinoma of the pancreas

We report a rare case of a non-insulin secreting malignant insulinoma of the pancreas and discuss its medical and surgical management. Surgical excision of malignant insulinoma produces good palliation and can increase survival.

Necrolytic migratory erythema, first symptom of a malignant glucagonoma: treatment by long-acting somatostatin and surgical resection. Report of three cases

We report three cases of malignant glucagonoma with necrolytic migratory erythema as the first clinical symptom. Long-acting somatostatin analogue was the first step of a multimodal therapeutic strategy which included surgical resection of the primary tumour in every case. Liver metastases which were present in two patients were treated by hepatic arterial chemoembolization and systemic chemotherapy in one case and by liver resection for cytoreduction and hepatic arterial chemoembolization in another case. Skin lesions resolved in all three patients.

Insulinoma: a review of current management

Insulinomas are a relatively rare tumour which occur predominantly in the pancreas. The majority of the tumours are benign, but have profound effects upon the patient. The diagnosis of insulinoma is often elusive, and the management may involve demanding surgery with a significant morbidity. In this review article, all clinical aspects of insulinomas are examined. Particular emphasis is placed on the myriad modes of presentation, and the methods used to localise the tumour pre-operatively. Medical, as well as surgical treatments are discussed and their role in the management of both malignant and benign tumours. Despite potential difficulties encountered in managing patients with this tumour, a large majority may be either cured or achieve useful palliation.

Vasoactive intestinal polypeptide-secreting tumours: biology and therapy

VIP-secreting tumours are rare, but they produce a dramatic clinical picture, the most prominent feature being profuse, watery diarrhoea and hypokalaemia. VIPomas are malignant and require sophisticated diagnostic and localization techniques in order to identify their presence. Delays in diagnosis are the rule rather than the exception. Improvements in the diagnosis of VIPomas appear to result in an increase in resectability rates. A definitive diagnosis is aided by the determination of plasma VIP concentrations through the use of sensitive radioimmunoassays. With heightened awareness of this syndrome, increasing numbers of patients can be identified and more effective treatments developed for the refractory and recurrent tumours.

Surgery and polychemotherapy of non-functional endocrine pancreatic tumors: a case report with a dramatic clinical response

Endocrine pancreatic tumors (EPT) are a rare clinical entity, representing 5% of all pancreatic tumors. Nonfunctional subtypes (NF-EPT) often present themselves at diagnosis in a locally advanced or metastatic stage. Therapeutic planning of these neoplasias is based on a multidisciplinary integration of surgery and medical treatments. The Authors describe a case of NF-EPT with massive metastatic spread after cytoreductive surgery, with impressive response to polychemotherapy with 5-fluorouracil, epirubicin and dacarbazine. The various options concerning chemotherapic treatment of these tumors are reviewed.

Islet cell tumors of the pancreas

Pancreatic endocrine neoplasms are a heterogeneous group of tumors that produce active hormones and result in distinct clinical syndromes. For the most part, they are malignant and require sophisticated diagnostic and localization techniques in order to identify their presence. Delays in diagnosis are the rule rather than the exception. Improvements in the diagnosis of gastrinomas and insulinomas appear to result in an increase in resectability rates. The widespread availability of intraoperative ultrasonography, as well as improved knowledge of the location of these tumors, has also had an impact on improved cure rates. With heightened awareness of these syndromes, increasing numbers of patients can be identified and more effective treatments developed for the refractory and recurrent tumors.