Surgery in malignant pancreatic neuroendocrine tumors

Prevalence of Sarcopenia and Impact on Survival in Patients with Metastatic Gastroenteropancreatic Neuroendocrine Tumours

Sarcopenia in patients with cancer is associated with adverse outcomes such as shorter survival. However, there exists little evidence regarding the prevalence of sarcopenia in patients with metastatic gastroenteropancreatic neuroendocrine tumours (GEP-NETs). Patients with a histologically confirmed newly diagnosed metastatic GEP-NET between 2006 and 2018, CT scan, and anthropometric data at diagnosis were included in this study. CT scans were analysed for the presence of sarcopenia and correlated with overall survival (OS). In total, 183 patients, 87 male (48%), with a median age of 62 years (IQR 52-68 years), were included. In 44 patients (24%), there was a pancreas NET, and in 136 patients, there was a small bowel NET (74%). Sarcopenia was present in 128 patients (69%) and unrelated to BMI (median 25.1). There were significant survival differences between patients with pancreatic and small bowel NETs at 86 vs. 141 months, respectively (p = 0.04). For patients with pancreatic NETs, the presence of sarcopenia was independently associated with shorter OS (HR 3.79 95% CI 1.1-13.03, p-value 0.035). A high prevalence of sarcopenia at the time of diagnosis of a metastatic GEP-NET was seen and associated with worse OS in patients with pancreatic NETs. Further research should focus on how to reverse sarcopenia and its impact on OS and/or quality of life.

Surgery, Liver Directed Therapy and Peptide Receptor Radionuclide Therapy for Pancreatic Neuroendocrine Tumor Liver Metastases

Pancreatic neuroendocrine tumors (PNETs) are described by the World Health Organization (WHO) classification by grade (1–3) and degree of differentiation. Grade 1 and 2; well differentiated PNETs are often characterized as relatively “indolent” tumors for which locoregional therapies have been shown to be effective for palliation of symptom control and prolongation of survival even in the setting of advanced disease. The treatment of liver metastases includes surgical and non-surgical modalities with varying degrees of invasiveness; efficacy; and risk. Most of these modalities have not been prospectively compared. This paper reviews literature that has been published on treatment of pancreatic neuroendocrine liver metastases using surgery; liver directed embolization and peptide receptor radionuclide therapy (PRRT). Surgery is associated with the longest survival in patients with resectable disease burden. Liver-directed (hepatic artery) therapies can sometimes convert patients with borderline disease into candidates for surgery. Among the three embolization modalities; the preponderance of data suggests chemoembolization offers superior radiographic response compared to bland embolization and radioembolization; but all have similar survival. PRRT was initially approved as salvage therapy in patients with advanced disease that was not amenable to resection or embolization; though the role of PRRT is evolving rapidly

Castleman Disease Mimicking Pancreatic Neuroendocrine Tumour: Interpretation of Positron Emission Tomography in Pancreatic Incidentaloma

We report a rare case of an incidental pancreatic lesion that proved to be Castleman disease in a peripancreatic lymph node, which mimicked a high-grade pancreatic neuroendocrine tumour (PNET) based on findings on positron emission tomography (PET). The disease was discovered as an incidental finding on CT imaging of the abdomen and was investigated and managed as PNET. Surgical resection was performed with distal pancreatectomy and splenectomy, however, histology revealed the lesion was a lymph node affected by Castleman disease. Often termed the great mimic, Castleman disease is a rare lymphoproliferative disorder that is often mistaken for other primary lesions of the organ due to its location and should be considered a differential of fluorodeoxyglucose (FDG)-avid PET lesions on imaging.

Current updates and future directions in diagnosis and management of gastroenteropancreatic neuroendocrine neoplasms

Gastroenteropancreatic neuroendocrine neoplasms are a heterogenous group of rare neoplasms that are increasingly being discovered, often incidentally, throughout the gastrointestinal tract with varying degrees of activity and malignant potential. Confusing nomenclature has added to the complexity of managing these lesions. The term carcinoid tumor and embryonic classification have been replaced with gastroenteropancreatic neuroendocrine neoplasm, which includes gastrointestinal neuroendocrine and pancreatic neuroendocrine neoplasms. A comprehensive multidisciplinary approach is important for clinicians to diagnose, stage and manage these lesions. While histological diagnosis is the gold standard, recent advancements in endoscopy, conventional imaging, functional imaging, and serum biomarkers complement histology for tailoring specific treatment options. In light of developing technology, our review sets out to characterize diagnostic and therapeutic advancements for managing gastroenteropancreatic neuroendocrine tumors, including innovations in radiolabeled peptide imaging, circulating biomarkers, and endoscopic treatment approaches adapted to different locations throughout the gastrointestinal system.

Benefit of Primary Tumor Resection in Stage IV, Grade 1 and 2, Pancreatic Neuroendocrine Tumors: A Propensity-Score Matched Cohort Study

Objective

To determine the association of primary tumor resection in stage IV pancreatic neuroendocrine tumors (Pan-NET) and survival in a propensity-score matched study.

Background

Pan-NET are often diagnosed with stage IV disease. The oncologic benefit from primary tumor resection in this scenario is debated and previous studies show contradictory results.

Methods

Patients from 3 tertiary referral centers from January 1, 1985, through December 31, 2019: Uppsala University Hospital (Uppsala, Sweden), Sahlgrenska University Hospital (Gothenburg, Sweden), and Brigham and Women's Hospital/Dana-Farber Cancer Institute (Boston, USA) were assessed for eligibility. Patients with sporadic, grade 1 and 2, stage IV pan-NET, with baseline 2000-2019 were divided between those undergoing primary tumor resection combined with oncologic treatment (surgery group [SG]), and those who received oncologic treatment without primary tumor resection (non-SG). A propensity-score matching was performed to account for the variability in the extent of metastatic disease and comorbidity. Primary outcome was overall survival.

Results

Patients with stage IV Pan-NET (n = 733) were assessed for eligibility, 194 were included. Patients were divided into a SG (n = 65) and a non-SG (n = 129). Two isonumerical groups with 50 patients in each group remained after propensity-score matching. The 5-year survival was 65.4% (95% CI, 51.5-79.3) in the matched SG and 47.8% (95% CI, 30.6-65.0) in the matched non-SG (log-rank, P = 0.043).

Conclusions

Resection of the primary tumor in patients with stage IV Pan-NET and G1/G2 grade was associated with prolonged overall survival compared to nonoperative management. A surgically aggressive regime should be considered where resection is not contraindicated.

Multimodal Management of Grade 1 and 2 Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (p-NETs) are rare tumors with a recent growing incidence. In the 2017 WHO classification, p-NETs are classified into well-differentiated (i.e., p-NETs grade 1 to 3) and poorly differentiated neuroendocrine carcinomas (i.e., p-NECs). P-NETs G1 and G2 are often non-functioning tumors, of which the prognosis depends on the metastatic status. In the localized setting, p-NETs should be surgically managed, as no benefit for adjuvant chemotherapy has been demonstrated. Parenchymal sparing resection, including both duodenum and pancreas, are safe procedures in selected patients with reduced endocrine and exocrine long-term dysfunction. When the p-NET is benign or borderline malignant, this surgical option is associated with low rates of severe postoperative morbidity and in-hospital mortality. This narrative review offers comments, tips, and tricks from reviewing the available literature on these different options in order to clarify their indications. We also sum up the overall current data on p-NETs G1 and G2 management.

Prior Resection of the Primary Tumor Prolongs Survival After Peptide Receptor Radionuclide Therapy of Advanced Neuroendocrine Neoplasms

OBJECTIVE

The aim of the study was to compare impact on survival after resection of primary tumors (PTs) after peptide receptor radionuclide therapy (PRRT).

BACKGROUND

PRRT is a highly effective therapeutic option to treat locally advanced or metastatic neuroendocrine neoplasms (NENs).

METHODS

We retrospectively analyzed the data of 889 patients with advanced NEN (G1-G3, stage IV) treated with at least 1 cycle of PRRT. In 486 of 889 patients (55%, group 1), PT had been removed before PRRT. Group 2 constituted 403 patients (45%) with no prior PT resection. Progression-free survival (PFS) and overall survival (OS) was determined by 68Ga SSTR-PET/CT in all patients applying RECIST and EORTC.

RESULTS

Most patients had their PT in pancreas (n = 335; 38%) and small intestine (n = 284; 32%). Both groups received a mean of 4 cycles of PRRT (P = 0.835) with a mean cumulative administered radioactivity of 21.6 ± 11.7 versus 22.2 ± 11.2 GBq (P = 0.407). Median OS in group 1 was 134.0 months [confidence interval (CI): 118-147], whereas OS in group 2 was 67.0 months (CI: 60-80; hazard ratio 2.79); P < 0.001. Likewise, the median progression-free survival after first PRRT was longer in group 1 with 18.0 (CI: 15-20) months as compared to group 2 with 14.0 (CI: 15-18; hazard ratio 1.21) months; P = 0.012.

CONCLUSIONS

A previous resection of the PT before PRRT provides a significant survival benefit in patients with NENs stage IV.

Rare case of pancreatic neuroendocrine tumour presenting as paraneoplastic hypercalcaemia

An asymptomatic 68-year-old woman who presented with an isolated hypercalcaemia was diagnosed with a rare, previously unsuspected parathyroid hormone-related peptide (PTHrP)-producing pancreatic neuroendocrine tumour. She underwent an extensive operation including vascular resection and reconstruction, resulting in successful removal of the tumour with negative margins. Medical and surgical management of pancreatic neuroendocrine tumours and PTHrP-mediated paraneoplastic hypercalcaemia is discussed.

Association of a Palliative Surgical Approach to Stage IV Pancreatic Neuroendocrine Neoplasms with Survival: A Systematic Review and Meta-Analysis

The role of primary tumor resection in patients with pancreatic neuroendocrine neoplasms (PanNENs) and unresectable distant metastases remains controversial. We aimed to evaluate the effect of palliative primary tumor resection (PPTR) on overall survival (OS) in this setting. We searched the MEDLINE, Embase, Cochrane Library, Web of Science and SCOPUS databases up to January 2020 and used the Newcastle–Ottawa scale (NOS) criteria to assess quality/risk of bias. A total of 5661 articles were screened. In 10 studies, 5551 unique patients with stage IV PanNEN and unresectable metastases were included. The five-year OS for PanNEN patients undergoing PPTR in stage IV was 56.6% vs. 23.9% in the non-surgically treated patients (random effects relative risk (RR): 1.70; 95% CI: 1.53–1.89). Adjusted analysis of pooled hazard ratios (HR) confirmed longer OS in PanNEN patients undergoing PPTR (random effects HR: 2.67; 95% CI: 2.24–3.18). Cumulative OS analysis confirmed an attenuated survival benefit over time. The complication rate of PPTR was as high as 27%. In conclusion, PPTR may exert a survival benefit in stage IV PanNEN. However, the included studies were subject to selection bias, and special consideration should be given to PPTR anchored to a multimodal treatment strategy. Further longitudinal studies are warranted, with long-term follow-up addressing the survival outcomes associated with surgery in stage IV disease.

The North American Neuroendocrine Tumor Society Consensus Paper on the Surgical Management of Pancreatic Neuroendocrine Tumors

This manuscript is the result of the North American Neuroendocrine Tumor Society consensus conference on the surgical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The group reviewed a series of questions of specific interest to surgeons taking care of patients with pancreatic neuroendocrine tumors, and for each, the available literature was reviewed. What follows are these reviews for each question followed by recommendations of the panel.

Heterogeneity of Vascular Endothelial Cells, De Novo Arteriogenesis and Therapeutic Implications in Pancreatic Neuroendocrine Tumors

Arteriogenesis supplies oxygen and nutrients in the tumor microenvironment (TME), which may play an important role in tumor growth and metastasis. Pancreatic neuroendocrine tumors (pNETs) are the second most common pancreatic malignancy and are frequently metastatic on presentation. Nearly a third of pNETs secrete bioactive substances causing debilitating symptoms. Current treatment options for metastatic pNETs are limited. Importantly, these tumors are highly vascularized and heterogeneous neoplasms, in which the heterogeneity of vascular endothelial cells (ECs) and de novo arteriogenesis may be critical for their progression. Current anti-angiogenetic targeted treatments have not shown substantial clinical benefits, and they are poorly tolerated. This review article describes EC heterogeneity and heterogeneous tumor-associated ECs (TAECs) in the TME and emphasizes the concept of de novo arteriogenesis in the TME. The authors also emphasize the challenges of current antiangiogenic therapy in pNETs and discuss the potential of tumor arteriogenesis as a novel therapeutic target. Finally, the authors prospect the clinical potential of targeting the FoxO1-CD36-Notch pathway that is associated with both pNET progression and arteriogenesis and provide insights into the clinical implications of targeting plasticity of cancer stem cells (CSCs) and vascular niche, particularly the arteriolar niche within the TME in pNETs, which will also provide insights into other types of cancer, including breast cancer, lung cancer, and malignant melanoma.

Palliative resection of primary site in advanced gastroenteropancreatic neuroendocrine tumors improves survivals

BACKGROUND/AIMS

Gastroenteropancreatic neuroendocrine tumors are rarely seen and have heterogeneous clinical outcomes. Mostly half of the patients had metastatic disease at presentation. Palliative resection of primary site in metastatic disease is still controversial. The aim of this study was to find out the influence of resection of primary tumor site on progression-free survival and overall survival in metastatic non-functioning gastroenteropancreatic neuroendocrine tumors. The secondary end point is to determine the prognostic factors influencing the survivals.

MATERIALS AND METHODS

This study was conducted at a single medical oncology center, Antalya Education and Research Hospital. Patients who had non-functioning metastatic gastroenteropancreatic neuroendocrine tumors with primary site resected or unresected were compared retrospectively. Resection of metastases was excluded.

RESULTS

Fifty-three patients were included in the study and 29 patients had primary tumor resection. The primary site resected group had favorable outcomes with the overall survival (median unreached) compared to the median overall survival of 30 months in the unresected group (p=0.001). Median progression-free survival was also better in the primary site resected group than the unresected group (60 months vs. 14 months, respectively) (p=0.013). In multivariate analysis, unresected primary site and high-grade tumors were found to be independent prognostic factors on low survivals (Hazard ratio (HR): 4.6; 95% CI: 1.21-17.47 and HR: 10.1; 95% CI: 1.15-88.84, respectively). Age (p=0.131), gender (p=0.051), chromogranin A level (p=0.104), Ki-67 index (p=0.550), tumor size (p=0.623), and primary tumor area (p=0.154) did not influence the overall survival.

CONCLUSION

Gastroenteropancreatic neuroendocrine tumors with primary site resected had improved survivals when compared to the unresected group.

A Systematic review and meta-analysis on the role of palliative primary resection for pancreatic neuroendocrine neoplasm with liver metastases

BACKGROUND

Role of palliative pancreatic neuroendocrine neoplasm (PanNEN) resection (pPanNEN-R) is controversial. This study was designed as a meta-analysis of studies which allow a comparison of pPanNEN-R and non-surgical management (PanNEN-nR).

METHODS

All published studies until 2017 allowing for the comparison of pPanNEN-R and PanNEN-nR were reviewed. Primary outcome was overall survival (OS). Secondary outcomes measures included postoperative morbidity, reoperation, readmission, length of hospital stay (LOS), and quality of life (QoL). Risk of death was compared by computing the odds-ratio (OR), while 5- and 10-year OS using weighted mean differences.

RESULTS

Seven studies were included. A total of 885 patients were included, of whom 252 (28%) underwent pPanNEN-R and 633 (72%) underwent PanNEN-nR. Overall quality of included studies was fair. The risk of death was significantly reduced in patients who underwent pPanNEN-R compared to those who underwent PanNEN-nR (OR = 0.38, 95% CI 0.23-0.65). Data on postoperative morbidity, reoperation, readmission, LOS, and QoL were not adequately reported therefore a meta-analysis for the secondary outcomes was not performed.

DISCUSSION

pPanNEN-R in patients with unresectable LM seems to be associated with a better OS compared to non-surgical management but the limitations of included studies does not allow firm conclusions.

Role of palliative resection of the primary pancreatic neuroendocrine tumor in patients with unresectable metastatic liver disease: a systematic review and meta-analysis

BACKGROUND

Treatment for pancreatic neuroendocrine tumors (PNETs) in patients with unresectable metastatic liver disease has long been a controversial issue. This systematic review aims to summarize the existing evidence concerning the value of primary tumor resection in this group of patients.

METHODS

A systematic review of the literature and a meta-analysis were performed. The PubMed and Cochrane databases were searched to identify articles that compared palliative primary tumor resection and nonsurgical regimens in patients with PNETs and unresectable liver metastases. Relevant articles were identified in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The primary outcome was overall survival. The included studies were evaluated for heterogeneity and publication bias.

RESULTS

Overall, 10 studies were included in the analysis. No randomized controlled trials (RCTs) were identified. These studies included 1,226 patients who underwent a resection of the primary tumor and 1,623 patients who did not undergo surgery. The median overall survival was 36-137 and 13.2-65 months in the surgical and nonsurgical groups, respectively, and the 5-year overall survival rate was 35.7-83 and 5.4%-50%, respectively, in these two groups. The meta-analysis demonstrated that there was no significant difference in liver tumor burden (odds ratio [OR] =1.51, 95% CI: 0.59-3.89, P=0.39) or tumor grade (OR =2.88, 95% CI: 0.92-9.04, P=0.07) among patients who underwent surgery and nonsurgical therapy. Furthermore, patients who underwent an aggressive surgical approach appeared to have a higher tumor grade. However, the meta-analysis demonstrated that patients who underwent primary tumor resection had better overall survival (P<0.001), with a pooled hazard ratio of 0.36 (95% CI: 0.30-0.45). No publication bias was detected.

CONCLUSION

This meta-analysis demonstrates that the palliative resection of the primary tumor in patients with PNETs and unresectable liver metastases can increase survival, although a bias toward a more aggressive surgical approach in patients with better performance status, less advanced disease, or a tumor located in the body or tail of the pancreas appears likely. RCTs with longer follow-up periods are required to confirm the advantages of palliative primary tumor resection for PNETs.

Role of surgery in pancreatic neuroendocrine tumor

Pancreatic neuroendocrine tumours (PNETs) are rare. They are generally accepted to be slow-growing and have an indolent course. These tumours can be non-functioning or functioning, consisting of a biochemically heterogeneous group of tumours including insulinomas, gastrinomas, carcinoids and glucagonomas. Although surgery remains the mainstay of treatment, controversy still exists especially for non-functioning tumours <2 cm in size. Whether these should be resected or undergo intensive surveillance remains unclear. The surgical approach depends on local expertise. Many studies have shown comparable short-term surgical outcome with laparoscopic pancreatic resection compared to open techniques, however data on long-term oncological outcome are still lacking. On the other hand, liver metastasis occurs in as high as 80% of PNET patients. Five-year survival rate is only 30% if left untreated compared to 60-80% if complete resection is achieved. Current evidence supports liver resection with an aim for symptomatic control and to improve survival in those with respectable disease and no extra-hepatic metastasis. Palliative debunking can be considered in those with intractable symptoms. This article reviews the current evidence on pancreatic resection for PNETs, in particular the role of laparoscopic resection and the management of liver metastasis.

Outcomes of 101 Consecutive Surgical Resections of Gastroenteropancreatic Neuroendocrine Tumours (GEPNETs) at Tata Memorial Hospital: a Referral Bias for Nonfunctional Duodenopancreatic Tumours and the Need for Greater Awareness of GEPNETs as a Distinct Entity

Data from India regarding the disease spectrum and surgical results of neuroendocrine tumours (GEPNETs) are sparse. Tempered surgical radicality in a high-volume oncology centre, conforming to existing guidelines, may further our understanding of tumour characteristics and behavioural patterns of nonfunctional GEPNETs. Surgical outcomes of patients with histopathologically confirmed GEPNETs from January 2003 to December 2013 were analyzed from a prospectively maintained database. Tumour grade, organ of primary tumour, perioperative factors, quality/radicality of resection and presence of metastatic disease were correlated with perioperative outcomes, overall survival and disease-free survival. Ninety of the 101 operated patients had nonfunctional tumours. These comprised radical resections (n = 69), organ-preserving procedures (n = 16) and inoperable tumours (n = 5). The primary tumour sites were pancreatic in 48 patients and gastroenteric in 42 patients. The overall perioperative morbidity and mortality rates were 30 and 3 %, respectively. Fifteen patients harboured metastatic disease at presentation. At a median follow-up of 22 months, 18 patients had residual disease, 7 developed recurrences and 10 patients died. The estimated actuarial 5-year overall survival was 81.6 %, and disease-free survival was 67.2 %. Tumour grade and organ of origin (pancreatic vs. gastroenteric) did not influence long-term survival (p = 0.315 and p = 0.624, respectively), but presence of metastatic disease at presentation significantly affected long-term survival (p = 0.009). Nonfunctional pancreatic/duodenal neuroendocrine tumours (NETs) accounted for 76 % of surgical resections at our centre with the minority being other resections. In selected patients with nonfunctional NETs, organ-preserving surgery may provide equivalent long-term survival with decreased operative morbidity. Although tumour grade is considered to be an important prognostic factor, the presence of metastatic disease at presentation also determines long-term survival. The referral bias suggests the need for greater awareness given the favourable long-term outcomes of these tumours. There is a need to correct this referral bias by increasing the awareness of GEPNETs in India.

Management Options for Advanced Low or Intermediate Grade Gastroenteropancreatic Neuroendocrine Tumors: Review of Recent Literature

Our understanding of the biology, genetics, and natural history of neuroendocrine tumors (NETs) of the gastrointestinal tract and pancreas has improved considerably in the last several decades and the spectrum of available therapeutic options is rapidly expanding. The management of patients with metastatic low or intermediate grade NETs has been revolutionized by the development of new treatment strategies such as molecular targeting therapies with everolimus and sunitinib, somatostatin analogs, tryptophan hydroxylase inhibitors, and peptide receptor radionuclide therapy that can be used alone or as a multimodal approach with or without surgery. To further define and clarify the utility, appropriateness, and the sequence of the growing list of available therapies for this patient population will require more high level evidence; however, data from well-designed randomized phase III clinical trials is rapidly accumulating that will further stimulate development of new management strategies. It is therefore important to thoroughly review emerging evidence and report major findings in frequent updates, which will expand our knowledge and contribute to a better understanding, characterization, and management of advanced NETs.

Imaging of secretory tumors of the gastrointestinal tract

Gastrointestinal secretory tumors, or gastroenteropancreatic neuroendocrine tumors, encompass a wide array of endocrine cell tumors. The significance of these tumors lies in their ability to alter physiology through hormone production as we well as in their malignant potential. Functioning tumors may present earlier due to symptomatology; conversely, non-functioning tumors are often diagnosed late as they reach large sizes, causing symptoms secondary to local mass effect. Imaging aids in the diagnosis, staging, and prognosis and provides key information for presurgical planning. Although most of these tumors are sporadic, some are associated with important syndromes and associations, knowledge of which is critical for patient management. In this article, we provide an overview of secretory and neuroendocrine tumors of the GI tract and pancreas.

Surgical treatment of non-functioning pancreatic neuroendocrine tumours based on three clinical scenarios

INTRODUCTION

The treatment of patients with non-functioning pancreatic neuroendocrine tumours (NFPNET) is resection in locally pancreatic disease, or with resectable liver metastases. There is controversy about unresectable liver disease.

METHODS

We analysed the perioperative data and survival outcome of 63 patients who underwent resection of NFPNET between 1993 and 2012. They were divided into 3 scenarios: A, pancreatic resection (44patients); B, pancreatic and liver resection in synchronous resectable liver metastases (12patients); and C, pancreatic resection in synchronous unresectable liver metastases (6patients). The prognostic factors for survival and recurrence were studied.

RESULTS

Distal pancreatectomy (51%) and pancreaticoduodenectomy (38%) were more frequently performed. Associated surgery was required in 44% of patients, including synchronous liver resections in 9patients. Two patients received a liver transplant during follow-up. According to the WHO classification they were distributed into G1: 10 (16%), G2: 45 (71%), and G3: 8 (13%). The median hospital stay was 11days. Postoperative morbidity and mortality were 49% and 1.6%, respectively. At the closure of the study, 43 (68%) patients were still alive, with a mean actuarial survival of 9.6years. The WHO classification and tumour recurrence were risk factors of mortality in the multivariate analysis. The median actuarial survival by scenarios was 131months (A), 102months (B), and 75months (C) without statistically significant differences.

CONCLUSIONS

Surgical resection is the treatment for NFPNET without distant disease. Resectable liver metastases in well-differentiated tumours must be resected. The resection of the pancreatic tumour with unresectable synchronous liver metastasis must be considered in well-differentiated NFPNET. The WHO classification grade and recurrence are risk factors of long-term mortality.

Resection of primary gastroenteropancreatic neuroendocrine tumors in the presence of irresectable liver metastases

Gastroenteropancreatic neuroendocrine tumors often present at an advanced stage and carry a variable prognosis, with many patients living long periods even with metastatic disease. Resection of the primary tumor when liver metastases are unresectable is a contentious subject with no consensus between existing guidelines. A number of recent studies have suggested a potential survival benefit as well as improved symptom control with resection. With variable results from nonoperative management strategies, the risk:benefit ratio of resection of the primary tumor may be favorable for carefully selected patients.

Surgical management for non-functional pancreatic neuroendocrine neoplasms with synchronous liver metastasis: A consensus from the Chinese Study Group for Neuroendocrine Tumors (CSNET)

Pancreatic neuroendocrine neoplasms (p-NENs) are slowly growing tumors with frequent liver metastasis. There is a variety of approaches to treat non-functional p-NENs with synchronous liver metastasis (LM) which complicates the determination of optimal treatment. Based on updated literature review, we discussed the treatment strategy determinants for p-NEN with LM. According to the resectability of primary tumor, the WHO 2010 grade classification and the radiological type of liver metastasis, the CSNET group reached agreements on a number of issues, including the following. Prior to treatment, biopsy is required to confirm pathology. Liver biopsy is important for more accurate grading of tumor and percutaneous core needle biopsy is more available than EUS-FNA. In patients with unresectable primary, surgical resection for liver-metastatic lesions should be avoided. Curative surgery is recommended for G1/G2 p-NET with type I LM and R1 resection also seems to improve overall survival rate. Cytoreductive surgery is recommended for G1/G2 p-NET with type II LM in select patients, and should meet stated requirements. Surgical resection for G1/G2 p-NET with type III LM and p-NEC with LM should be avoided, and insufficient evidence exists to guide the surgical treatment of G3 p-NET with LM. Liver transplantation may be an option in highly select patients. In addition, the optimal time for surgical approach is still required for more evidence.

Multidisciplinary management of nonfunctional neuroendocrine tumor of the pancreas

Pancreatic neuroendocrine tumors (PNETs) are a rare and diverse group of tumors; nonfunctional (NF) PNETs account for the majority of cases. Most patients with NF-PNETs have metastatic disease at the time of presentation. A variety of treatment modalities exist, including medical, liver directed, and surgical treatments. Aggressive surgical management is associated with prolonged survival, however available data are limited by selection bias and the frequent combination of PNETs with carcinoid tumors. Although few patients with metastatic disease will be cured, application of currently available therapies in a multidisciplinary setting can lead to excellent outcomes with prolonged patient survival.

Postoperative Complications, In-Hospital Mortality and 5-Year Survival After Surgical Resection for Patients with a Pancreatic Neuroendocrine Tumor: A Systematic Review

Studies on postoperative complications and survival in patients with pancreatic neuroendocrine tumors (pNET) are sparse and randomized controlled trials are not available. We reviewed all studies on postoperative complications and survival after resection of pNET. A systematic search was performed in the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE from 2000-2013. Inclusion criteria were studies of resected pNET, which described postoperative complications separately for each surgical procedure and/or 5-year survival after resection. Prospective and retrospective studies were pooled separately and overall pooled if heterogeneity was below 75%. The random-effect model was used. Overall, 2643 studies were identified and after full-text analysis 62 studies were included. Pancreatic fistula (PF) rate of the prospective studies after tumor enucleation was 45%; PF-rates after distal pancreatectomy, pancreatoduodenectomy, or central pancreatectomy were, respectively, 14-14-58%. Delayed gastric emptying rates were, respectively, 5-5-18-16%. Postoperative hemorrhage rates were, respectively, 6-1-7-4%. In-hospital mortality rates were, respectively, 3-4-6-4%. The 5-year overall survival (OS) and disease-specific survival (DSS) of resected pNET without synchronous resected liver metastases were, respectively, 85-93%. Heterogeneity between included studies on 5-year OS in patients with synchronous resected liver metastases was too high to pool all studies. The 5-year DSS in patients with liver metastases was 80%. Morbidity after pancreatic resection for pNET was mainly caused by PF. Liver resection in patients with liver metastases seems to have a positive effect on DSS. To reduce heterogeneity, ISGPS criteria and uniform patient groups should be used in the analysis of postoperative outcome and survival.

Role of Locoregional and Systemic Approaches for the Treatment of Patients with Metastatic Neuroendocrine Tumors

Although gastroenteropancreatic neuroendocrine tumors are often perceived as being indolent tumors, more than half of the patients will harbor liver metastases at the time of diagnosis. Gastroenteropancreatic neuroendocrine tumors have the potential to be aggressive and resistant to therapy, making the integration of both locoregional and systemic therapy even more critical in the treatment of patients with locally advanced or metastatic lesions. Over the last several years, significant advancements have been made in the surgical treatment, liver-directed therapy, and medical management of gastroenteropancreatic neuroendocrine tumors. While surgical resection is the cornerstone of therapy, cytoreductive surgery, orthotopic liver transplantation, local ablation, and intra-arterial therapy all improve the prognosis of patients suffering with locally advanced or metastatic disease. In addition, great strides have been made in the medical management of gastroenteropancreatic neuroendocrine tumors, particularly with the evolution of novel molecular targeted therapy, such as everolimus and sunitinib. Hence, gastroenteropancreatic neuroendocrine tumor is becoming a disease process requiring more of a multi-disciplinary approach with the integration of both locoregional and systemic therapies for improved outcomes.

Palliative resection of the primary tumor in 442 metastasized neuroendocrine tumors of the pancreas: a population-based, propensity score-matched survival analysis

PURPOSE

There is an ongoing debate on whether palliative removal of the primary tumor may result in a survival benefit for patients with incurable stage IV pancreatic neuroendocrine tumors (P-NET). The objective of this study was to assess whether palliative resection of the primary tumor in patients with incurable stage IV P-NET has an impact on survival.

METHODS

Patients with stage IV P-NET registered in the Surveillance, Epidemiology, and End Results database between 2004 and 2011 were identified. Those undergoing resection of metastases were excluded. Overall and cancer-specific survival of patients who did and did not undergo resection of their primary tumor were compared by means of risk-adjusted Cox proportional hazard regression analysis and propensity score-matched analysis.

RESULTS

A total of 442 stage IV P-NET patients were identified, of whom 75 (17.0 %) underwent palliative primary tumor resection. The latter showed a significant benefit in both overall survival (hazard ratio [HR] of death = 0.41, 95 % confidence interval [CI] 0.25-0.66, p < 0.001) and cancer-specific survival (HR of death = 0.41, 95 % CI 0.25-0.67, p < 0.001) in unadjusted multivariate Cox regression analysis; the benefit persisted after propensity score adjustment.

CONCLUSIONS

This population-based analysis of stage IV P-NET patients provides compelling evidence that palliative resection of the primary tumor is associated with significant survival benefit. Thus, the recent recommendations judging resection of the primary as inadvisable and the accompanying trend towards fewer palliative resections of the primary tumor have to be contested.

Meta-analysis of Liver Resection Versus Nonsurgical Treatments for Pancreatic Neuroendocrine Tumors with Liver Metastases

PURPOSE

Studies have reported limited evidence of the benefits and harms of various regimens, such as liver resection and medical therapy, for the treatment of pancreatic neuroendocrine tumors (pNETs) with liver metastases. This meta-analysis aimed to evaluate the efficacy of liver resection versus nonsurgical treatments in patients with pNET.

METHODS

Relevant studies published in English were retrieved from the computerized databases Medline, Embase, and Cochrane. A meta-analysis was performed to investigate the differences in the efficacy of liver resection and nonsurgical treatments based on the evaluation of 30-day mortality, symptom relief rate, median survival time, and 2-, 3-, or 5-year survival using a random-effects model. Studies were independently reviewed by two investigators. Data from eligible studies were extracted, and the meta-analysis was performed using the comprehensive meta-analysis program version 2.

RESULTS

A total of seven studies were included in the analysis. The results demonstrated that liver resection was significantly associated with a higher rate of symptom relief, longer median survival time, higher 2- or 3-year survival rates, as well as a higher 5-year survival rate. There was no significant difference in 30-day mortality among patients with pNETs who were treated by liver resection and nonsurgical therapy or survival between functional and nonfunctional pNETs. No publication bias was detected.

CONCLUSIONS

Liver resection has a favorable prognostic outcome in terms of higher postoperative symptom relief rates and longer survival rates. Further randomized, controlled trials with longer follow-up periods are required to confirm the advantages of liver resection for pNETs.

Surgical resection improves the outcome of the patients with neuroendocrine tumor liver metastases: large data from Asia

How to properly manage neuroendocrine liver metastasis (NELM) remains debatable, and only limited clinical data have been published from Asian population. The objective of this study is to identify possible prognostic factors affecting overall survival time and to provide a guideline for future clinical practice. A retrospective study was performed on 1286 patients who had neuroendocrine tumors in our specialized center, and data from 130 patients who had NELM were summarized. Demographic and clinicopathologic data, tumor grade, treatment method, and prognosis were statistically analyzed. Most of the NELMs originated from pancreas (65.4%). Important prognostic factors that included tumor location and size were identified with multivariate analysis. Patients with either primary tumor resection or liver metastasis resection showed a 5-year survival of 35.7% or 33.3%, respectively, whereas resection of both resulted in a 50% 5-year survival. More importantly, resection was performed on 7 patients with grade 3 (G3) tumors, and resulted in 1-year, 3-year, and 5-year survival of 100%, 42.8%, and 28.6%, respectively, whereas the other 9 G3 patients without resection died within 3 years. P = 0.49 comparing the resected group with nonresected group in G3 patients. Besides, the overall 5-year survival rates for resected and nonresected patients were 40.5% and 5.4%, respectively. Multiple prognostic factors influenced the overall outcome of NELM including patient age, tumor location, and size, etc. Aggressive surgical approaches could be considered for maximum survival time disregarding the pathological grade of the tumor. Study with larger sample size should be considered to reevaluate the recommendation of the WHO guidelines for G3 neuroendocrine tumors.

GEP-NETS update: a review on surgery of gastro-entero-pancreatic neuroendocrine tumors

The incidence of neuroendocrine tumors (NETs) has increased in the last decades. Surgical treatment encompasses a panel of approaches ranging from conservative procedures to extended surgical resection. Tumor size and localization usually represent the main drivers in the choice of the most appropriate surgical resection. In the presence of small (<2 cm) and asymptomatic nonfunctioning NETs, a conservative treatment is usually recommended. For localized NETs measuring above 2 cm, surgical resection represents the cornerstone in the management of these tumors. As they are relatively biologically indolent, an extended resection is often justified also in the presence of advanced NETs. Surgical options for NET liver metastases range from limited resection up to liver transplantation. Surgical choices for metastatic NETs need to consider the extent of disease, the grade of tumor, and the presence of extra-abdominal disease. Any surgical procedures should always be balanced with the benefit of survival or relieving symptoms and patients' comorbidities.

Surgical management of advanced pancreatic neuroendocrine tumors: short-term and long-term results from an international multi-institutional study

BACKGROUND

The role of extended resections in the management of advanced pancreatic neuroendocrine tumors (PNETs) is not well defined.

METHODS

Between 1995 and 2012, 134 patients with PNET underwent isolated (isoPNET group: 91 patients) or extended pancreatic resection (synchronous liver metastases and/or adjacent organs) (advPNET group: 43 patients).

RESULTS

The associated resections included 27 hepatectomies, 9 vascular resections, 12 colectomies, 10 gastrectomies, 4 nephrectomies, 4 adrenalectomies, and 3 duodenojejunal resections. R0 was achieved in 41 patients (95%) in the advPNET. The rates of T3-T4 (73 vs 16%; p < .0001) and N+ (35 vs 13%; p = .007) were higher in the advPNET group. Mortality (5 vs 2%) and major morbidity (21 vs 19%) rates were similar between the 2 groups. The 5-year overall survival (OS) of the series was 87% in the isoPNET group and 66% in the advPNET group (p = .006). Only patients with both locally advanced disease and liver metastases showed worse survival (p = .0003). The advPNET group developed recurrence earlier [disease-free survival (DFS) at 5 years: 26 vs 81%; p < .001]. In univariate analysis, negative prognostic factors of survival were: poor degree of differentiation (p < .001), liver metastasis (p = .011), NE carcinoma (p < .001), and resection of adjacent organs (p = .013). The multivariate analysis did not highlight any factor that influenced OS. In multivariate analysis independent DFS factors were a poor degree of differentiation (p = .03) and the European Neuroendocrine Tumor Society stage (p = .01).

CONCLUSIONS

An aggressive surgical approach for locally advanced or metastatic tumors is safe and offers long-term survival.

Pancreatic neuroendocrine tumors: current opinions on a rare, but potentially curable neoplasm

Pancreatic neuroendocrine tumors (PNETs) share a unique genetic identity, functional behavior, and clinical course. Compared with tumors of the exocrine pancreas, they are rare and show a different biologic behavior and prognosis. On the basis of data from recent studies, all PNETs, outside of small insulinomas, should be considered potentially malignant and treated accordingly. Untreated tumors have a high possibility to grow locally into adjacent structures or spread to distant organs. Although surgical excision irrespective of tumor functioning or nonfunctioning state remains the cornerstone of therapy, providing the best disease-free and survival rates to date, the understanding of the genetic nature of the disease yields new 'targets' to consider in drug development. The aim of this review is to summarize all recent advances of genetic research and new drug development in terms of PNETs, especially their genetic identity and subsequent alterations leading to the development of near or total malignant activity, and the new medical treatment strategies of this potentially curable disease on the basis of therapeutical agents acting, where possible, at the genetic level.

Pancreatic neuroendocrine tumor: A multivariate analysis of factors influencing survival

BACKGROUND

The outcomes of pancreatic neuroendocrine tumors are extremely diverse, and determining the best strategy, optimal timing of therapy and the therapeutic results depend on understanding prognostic factors. We determined the clinical, radiological and histological factors associated with survival and tumor recurrence for patients with pancreatic neuroendocrine tumor.

METHODS

From January 1, 1991 to December 31, 2011, 127 patients with pancreatic neuroendocrine tumor underwent pancreatectomy. The variables including clinical characteristics, surgical data and pathological findings were examined by univariate and multivariate analyses.

RESULTS

There were 103 patients with non-functional tumors (81%). Sixty-four patients (50%) underwent left pancreatectomy, 51 (42%) patients underwent pancreatico-duodenectomy, 12 (9%) patients underwent enucleation and 2 patients (1%) underwent central pancreatectomy. Forty-eight patients (38%) had synchronous liver metastases. Six patients (5%) required portal vein resection, and 19 (15%) patients required enlarged "en-bloc" resection of adjacent organs. The overall morbidity and mortality rates were 48% and 2.3%, respectively. The 1-, 3- and 5-year overall survival rates were 94%, 84%, and 74%, respectively. In multivariate analyses, synchronous liver metastases (p = 0.02) and portal vein resection (p < 0.01) were independent prognostic factors of survival.

CONCLUSIONS

Synchronous liver metastases and portal vein resection were found to be independent factors influencing survival.

Laparoscopic resection of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (PNETs) are a rare heterogeneous group of endocrine neoplasms. Surgery remains the best curative option for this type of tumor. Over the past two decades, with the development of laparoscopic pancreatic surgery, an increasingly larger number of PNET resections are being performed by these minimally-invasive techniques. In this review article, the various laparoscopic surgical options for the excision of PNETs are discussed. In addition, a summary of the literature describing the outcome of these treatment modalities is presented.

Pancreatic neuroendocrine tumours: hypoenhancement on arterial phase computed tomography predicts biological aggressiveness

BACKGROUND

Contrary to pancreatic adenocarcinoma, pancreatic neuroendocrine tumours (PNET) are commonly hyperenhancing on arterial phase computed tomography (APCT). However, a subset of these tumours can be hypoenhancing. The prognostic significance of the CT appearance of these tumors remains unclear.

METHODS

From 2001 to 2012, 146 patients with well-differentiated PNET underwent surgical resection. The degree of tumour enhancement on APCT was recorded and correlated with clinicopathological variables and overall survival.

RESULTS

APCT images were available for re-review in 118 patients (81%). The majority had hyperenhancing tumours (n = 80, 68%), 12 (10%) were isoenhancing (including cases where no mass was visualized) and 26 (22%) were hypoenhancing. Hypoenhancing PNET were larger, more commonly intermediate grade, and had higher rates of lymph node and synchronous liver metastases. Hypoenhancing PNET were also associated with significantly worse overall survival after a resection as opposed to isoenhancing and hyperenhancing tumours (5-year, 54% versus 89% versus 93%). On multivariate analysis of factors available pre-operatively, only hypoenhancement (HR 2.32, P = 0.02) was independently associated with survival.

DISCUSSION

Hypoenhancement on APCT was noted in 22% of well-differentiated PNET and was an independent predictor of poor outcome. This information can inform pre-operative decisions in the multidisciplinary treatment of these neoplasms.

Resection of the primary pancreatic neuroendocrine tumor in patients with unresectable liver metastases: possible indications for a multimodal approach

BACKGROUND

Pancreatic neuroendocrine tumors (PNETs) present in more than 50% of cases with liver metastases as the only systemic localization. Liver metastases are unresectable in 80% of cases at diagnosis. In the context of a metastatic disease, the benefit of primary tumor removal in terms of survival is controversial.

METHODS

A single-center series of patients with PNETs presenting with synchronous unresectable hepatic metastases and treated within a framework of a multidisciplinary team was analyzed retrospectively to assess the prognostic factors and the potential benefit of primary tumor resection on long-term survival.

RESULTS

At the time of diagnosis, 12 of 43 patients (28%) underwent primary tumor resection. After a median follow-up of 5 years (range, 0.6-14 years), 22 disease-related deaths were observed. The corresponding 5-year survival and median disease-specific duration of survival were 58% and 77 months, respectively. In the operated and nonoperated patients the 5-year disease-specific survival was 82% and 50%, respectively (P = .027). At multivariate analysis, patients with primary tumor removed had an improved survival compared with patients who did not (hazard ratio 0.18; 95% CI 0.05-0.66; P = .010). Other important factors associated with improved survival at multivariate analysis were lesser age, lesser Ki-67 index, and 25% less liver tumor burden.

CONCLUSION

In the present series of patients with PNETs and unresectable liver metastases, resection of the primary tumor was associated with an improved survival. This observation suggests that resection of the primary tumor should be part of a global therapeutic strategy and its indication and timing should be discussed within a multidisciplinary team.

Pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (pancreatic NETs) are rare, low- to intermediate-grade neoplasms thought to arise from the pancreatic islets. Recent advances in pathology and our understanding of the biological behavior of this group of tumors has resulted in changes in their nomenclature and how we treat them. This review puts into perspective our current understanding of pancreatic NETs in terms of their incidence, pathology, and management.

Prognostic factors and long-term outcome of pancreatic neuroendocrine neoplasms: Ki-67 index shows a greater impact on survival than disease stage. The large experience of the Spanish National Tumor Registry (RGETNE)

INTRODUCTION

Pancreatic neuroendocrine neoplasms (PNENs) are uncommon neoplasms with a wide spectrum of clinical behavior. The objective of this study was to assess in a large cohort of patients the relative impact of prognostic factors on survival.

METHODS

From June 2001 through October 2010, 1,271 patients were prospectively registered online (www.getne.org) at the Spanish National Cancer Registry for Gastroenteropancreatic Neuroendocrine Tumors (RGETNE) by participating centers. Clinical and histopathological features were assessed as potential prognostic factors by uni- and multivariate analyses.

RESULTS

Of 483 PNENs, 171 (35%) were functional (F) and 312 (65%) non-functional (NF). NF-PNENs were associated with a higher incidence of histological features denoting more aggressive disease, such as poor tumor differentiation, Ki-67 >20%, or vascular invasion (NF- vs. F-PNENs, respectively, p < 0.05). Nevertheless, functionality was not a significant predictor of survival (p = 0.19). Stage at diagnosis, Ki-67 index, tumor differentiation and surgical resection of the primary tumor were all significant prognostic factors in univariate analysis. However, Ki-67 (>20 vs. ≤2%) (hazard ratio (HR) 2.21, p = 0.01) and surgical resection (yes vs. no) (HR 0.92, p = 0.001) were the only independent predictors of survival in multivariate analysis. Among patients who underwent surgery, high Ki-67 index (HR 10.37, p = 0.02) and poor differentiation (HR 8.16, p = 0.03) were the only independent predictors of clinical outcome.

CONCLUSION

Ki-67 index and tumor differentiation are key prognostic factors influencing survival of patients with PNENs and, in contrast to what it is observed for other solid malignancies, they seem to have a greater impact on survival than the extent of disease. This should be borne in mind by physicians in order to appropriately tailor therapeutic strategies and surveillance of these patients.

Pancreatic neuroendocrine tumors: biology, diagnosis,and treatment

Pancreatic neuroendocrine tumors (PNETs), a group of endocrine tumors arising in the pancreas, are among the most common neuroendocrine tumors. The genetic causes of familial and sporadic PNETs are somewhat understood, but their molecular pathogenesis remains unknown. Most PNETs are indolent but have malignant potential. The biological behavior of an individual PNET is unpredictable; higher tumor grade, lymph node and liver metastasis, and larger tumor size generally indicate a less favorable prognosis. Endocrine testing, imaging, and histological evidence are necessary to accurately diagnose PNETs. A 4-pronged aggressive treatment approach consisting of surgery, locoregional therapy, systemic therapy, and complication control has become popular in academic centers around the world. The optimal application of the multiple systemic therapeutic modalities is under development; efficacy, safety, availability, and cost should be considered when treating a specific patient. The clinical presentation, diagnosis, and treatment of specific types of PNETs and familial PNET syndromes, including the novel Mahvash disease, are summarized.

Pancreatic neuroendocrine tumors with involved surgical margins: prognostic factors and the role of adjuvant radiotherapy

PURPOSE

Pancreatic neuroendocrine tumors (pNET) are rare neoplasms associated with poor outcomes without resection, and involved surgical margins are associated with a worse prognosis. The role of adjuvant radiotherapy (RT) in these patients has not been characterized.

METHODS AND MATERIALS

We retrospectively evaluated 46 consecutive patients with positive or close (<1 mm) margins after pNET resection, treated from 1983 to 2010, 16 of whom received adjuvant RT. Median RT dose was 50.4 Gy in 1.8-Gy fractions; half the patients received concurrent chemotherapy with 5-fluorouracil or capecitabine. No patients received adjuvant chemotherapy. Cox multivariate analysis (MVA) was used to analyze factors associated with overall survival (OS).

RESULTS

Median age at diagnosis was 56 years, and 52% of patients were female. Median tumor size was 38 mm, 57% of patients were node-positive, and 11% had a resected solitary liver metastasis. Patients who received RT were more likely to have larger tumors (median, 54 mm vs. 30 mm, respectively, p = 0.002) and node positivity (81% vs. 33%, respectively, p = 0.002) than those not receiving RT. Median follow-up was 39 months. Actuarial 5-year OS was 62% (95% confidence interval [CI], 41%-77%). In the group that did not receive RT, 3 patients (10%) experienced local recurrence (LR) and 5 patients (18%) developed new distant metastases, while in the RT group, 1 patient (6%) experienced LR and 5 patients (38%) developed distant metastases. Of all recurrences, 29% were LR. On MVA, male gender (adjusted hazard ratio [AHR] = 3.81; 95% CI, 1.21-11.92; p = 0.02) and increasing tumor size (AHR = 1.02; 95% CI, 1.01-1.04; p = 0.007) were associated with decreased OS.

CONCLUSIONS

Long-term survival is common among patients with involved-margin pNET. Despite significantly worse pathologic features among patients receiving adjuvant RT, rates of LR between groups were similar, suggesting that RT might aid local control, and merits further evaluation.

Role of resection of the primary pancreatic neuroendocrine tumour only in patients with unresectable metastatic liver disease: a systematic review

BACKGROUND

Surgery remains the only curative option for pancreatic neuroendocrine tumours (PNETs), but its indication is limited by metastatic disease in most patients. Indication for removing the primary lesion only in the setting of unresectable liver disease is controversial. The present systematic review aims at determining the potential bene- fits (survival, progression-free survival) or harms (morbidity, mortality) of surgical resection of the primary lesion only in patients with PNETs and unresectable metastases.

METHODS

Medline was queried for studies reporting the outcome of PNET patients with unresectable liver metastases whenever there was an explicit comparison between resection of the primary lesion only ('active treatment') and no resection ('non-active treatment'). The primary outcome was survival; possible secondary outcomes were progression-free survival, treatment-related mortality and morbidity, and relief of symptoms.

RESULTS

Only 3 cohort studies found were eligible and analysed; no meta-analysis could be performed. The number of patients undergoing 'active treatment' varied from 16 to 20, with a percentage ranging from 17 to 39% of cohorts. Survival was longer in patients who received 'active treatment' in 2 studies, and the 5-year survival rate also seemed higher, without significant complications.

DISCUSSION

Available data suggest a possible benefit of resection of the primary lesion only in this setting. However, a bias towards a more aggressive surgical approach in patients with a better performance status or less advanced disease seems likely, and no conclusion can be drawn except for the need of randomised trials. We calculated that such a trial would require at least 118 patients per arm.

Surgical resection and multidisciplinary care for primary and metastatic pancreatic islet cell carcinomas

INTRODUCTION

The role of multidisciplinary management of islet cell cancers (ICC) has not been fully investigated in a population-based setting.

METHODS

The Los Angeles County Cancer Surveillance Program was assessed for patients with ICC between the years 1982 to 2006. Patients were stratified by treatment received and clinicopathologic characteristics and survival were compared.

RESULTS

We identified 236 patients with ICC; 86 patients underwent curative-intent surgery with median survival for local, regional, and distant disease of 17.3, 12.2, and 4.0 years, respectively. In comparison, 102 patients underwent medical management alone; survival was significantly shorter when compared to the surgical cohort for local, regional, and distant disease (p < 0.05). To determine whether adjuvant chemotherapy was associated with improved survival, we compared patients who underwent surgery alone compared to patients who underwent surgery followed by adjuvant chemotherapy. Although patients with metastatic disease had 3-year longer survival with adjuvant chemotherapy, these improvements in survival were not statistically significant.

CONCLUSION

Surgical resection was associated with improved survival compared to medical management for any extent of disease in patients with ICC. Furthermore, adjuvant chemotherapy was not associated with survival but does warrant further examination in patients with metastatic disease.

One hundred thirty resections for pancreatic neuroendocrine tumor: evaluating the impact of minimally invasive and parenchyma-sparing techniques

BACKGROUND

Increasingly, surgeons apply minimally invasive and parenchyma-sparing techniques to the management of pancreatic neuroendocrine tumor (PNET). The aim of this study was to evaluate the impact of these approaches on patient outcomes.

METHODS

We retrospectively collected data on patients with PNET and compared perioperative and pathologic variables. Survival was analyzed using the Kaplan-Meier method. Factors influencing survival were evaluated using a Cox proportional hazards model.

RESULTS

One hundred thirty patients underwent resection for PNET. Traditional resections included 43 pancreaticoduodenectomies (PD), 38 open distal pancreatectomies (DP), and four total pancreatectomies. Minimally invasive and parenchyma-sparing resections included 25 laparoscopic DP, 11 central pancreatectomies, five enucleations, three partial pancreatectomies, and one laparoscopic-assisted PD. Compared to traditional resections, the minimally invasive and parenchyma-sparing resections had shorter hospital stays. By univariate analysis of neuroendocrine carcinoma, liver metastases and positive resection margins correlated with poor survival. There was an increase in minimally invasive or parenchyma-sparing resections over the study period with no differences in morbidity, mortality, or survival.

CONCLUSION

In this series, there has been a significant increase in minimally invasive and parenchyma-sparing techniques for PNET. This shift did not increase morbidity or compromise survival. In addition, minimally invasive and parenchyma-sparing operations yielded shorter hospital stays.

Post-surgical Pancreatitis Masquerading as Recurrent Neuroendocrine Cancer

Neuroendocrine tumours of the pancreas can have a spectrum of behaviour from relatively benign to aggressive. Resection can result in cure although metastatic disease is described. We present an unusual case of an apparent local recurrence of previously resected neuroendocrine tumour in a young man who had undergone distal pancreatectomy. Pathological analysis demonstrated focal post-surgical pancreatitis with radiological appearances bearing striking similarity to the original primary tumour.

Surgery and staging of pancreatic neuroendocrine tumors: a 14-year experience

BACKGROUND

The aims of this study were to evaluate contemporary outcomes associated with the surgical management of pancreatic neuroendocrine tumors (PNETs) and to assess the prognostic value of the World Health Organization (WHO) classification and TNM staging for PNETs.

METHODS

The medical records of 73 consecutive patients with PNETs treated at a single institution from January 1992 through September 2006 were reviewed. Survival was analyzed with the Kaplan-Meier method (median follow-up: 43 months).

RESULTS

Median patient age was 52 years (range, 19-83 years), and 36 (49%) patients were male. Thirty-three patients had a well-differentiated neuroendocrine tumor (WDT), 26 had a well-differentiated neuroendocrine carcinoma (WDCa), and 14 had a poorly differentiated neuroendocrine carcinoma (PDCa). Fifty (68%) patients underwent potentially curative resection, and the 5-year disease-specific survival (DSS) rate for the entire cohort was 62%. WHO classification and TNM staging system provided good prognostic stratification of patients; 5-year DSS rates were 100% for WDT, 57% for WDCa, 8% for PDCa, respectively, by WHO classification (p < 0.001), and 100% for stage 1, 90% for stage 2, 57% for stage 3, and 8% for stage 4, respectively, by TNM stage (p < 0.001). Among the patients who underwent potentially curative resection, nodal status, distant metastasis, and tumor grade were significant prognostic factors.

CONCLUSION

WHO classification and TNM staging are useful for prognostic stratification among patients with PNETs.