Value of Surgical Cytoreduction in Patients with Small Intestinal Neuroendocrine Tumors Metastatic to the Liver and Peritoneum

BACKGROUND

Cytoreductive hepatectomy can improve survival and symptoms of hormonal excess in patients with small intestinal neuroendocrine tumor (siNET) liver metastases, but whether to proceed when peritoneal metastases are encountered at the time of planned cytoreductive hepatectomy is controversial.

METHODS

This was a retrospective review of patients who underwent surgical management of metastatic siNETs at Mayo Clinic between 2000 and 2020. Patients who underwent cytoreductive operation for isolated liver metastases or both liver and peritoneal metastases were compared.

RESULTS

Of 261 patients who underwent cytoreductive operation for siNETs, 211 had isolated liver metastases and 50 had liver and peritoneal metastases. Complete cytoreduction was achieved in 78% of patients with isolated liver metastases and 56% of those with liver and peritoneal metastases (p = 0.002). After complete cytoreduction, median overall survival (OS) was 11.5 years for isolated liver metastases and 11.2 years for liver and peritoneal metastases (p = 0.10), and relief of carcinoid syndrome was ≥ 97% in both groups. After incomplete cytoreduction with debulking of > 90% of hepatic disease and/or closing Lyon score of 1-2, median OS was 6.4 years for isolated liver metastases and 7.1 years for liver and peritoneal metastases (p = 0.12).

CONCLUSIONS

Patients with siNETs metastatic to both the liver and peritoneum have favorable outcomes after aggressive surgical cytoreduction, with the best outcomes observed after complete cytoreduction. Therefore, the presence of peritoneal metastases should not by itself preclude surgical cytoreduction in this population.

Contemporary Approaches to the Surgical Management of Pancreatic Neuroendocrine Tumors

The incidence of pancreatic neuroendocrine tumors (PNETs) is on the rise primarily due to the increasing use of cross-sectional imaging. Most of these incidentally detected lesions are non-functional PNETs with a small proportion of lesions being hormone-secreting, functional neoplasms. With recent advances in surgical approaches and systemic therapies, the management of PNETs have undergone a paradigm shift towards a more individualized approach. In this manuscript, we review the histologic classification and diagnostic approaches to both functional and non-functional PNETs. Additionally, we detail multidisciplinary approaches and surgical considerations tailored to the tumor's biology, location, and functionality based on recent evidence. We also discuss the complexities of metastatic disease, exploring liver-directed therapies and the evolving landscape of minimally invasive surgical techniques.

Review of Merkel cell carcinoma with solitary pancreatic metastases mimicking primary neuroendocrine tumor of the pancreas

OBJECTIVE/BACKGROUND

Merkel cell carcinoma (MCC) but metastases to the pancreas are very rare. There are only a few cases of isolated metastases of MCC to the pancreas. Because of this rarity, it can be wrongly diagnosed as a neuroendocrine tumor of the pancreas(pNET), especially the poorly differentiated neuroendocrine carcinoma (PNEC) subtype, in which the treatment is vastly different than that of MCC with isolated metastases of the pancreas.

METHODS

An electronic search of the PubMed and google scholar databases was performed to obtain the literature on MCC with pancreatic metastases, using the following search terms: Merkel cell carcinoma, pancreas, and metastases. Results are limited to the following available article types: case reports and case series. We identified 45 cases of MCC with pancreatic metastases from the PubMed and Google Scholar database search and examined their potential relevance. Only 22 cases with isolated pancreatic metastases were taken for review including one case that we encountered.

RESULTS

The results from our review of cases of isolated pancreatic metastases of MCC were compared to the characteristics of the poorly differentiated pancreatic neuroendocrine tumor (PNEC). We found the following: (a) MCC with isolated pancreatic metastases occurred at an older age than PNEC and with male gender predominance (b) Most of the metastases occurred within 2 years of initial diagnosis of MCC (c) Resection of pancreatic mass was the first line treatment in case of resectable PNECs whereas resection of metastases was infrequently performed in MCC with pancreatic metastases.

Safety and Outcomes of Combined Pancreatic and Hepatic Resections for Metastatic Pancreatic Neuroendocrine Tumors

Background

Approximately 40–50% of patients with pancreatic neuroendocrine tumors (pNETs) initially present with distant metastases. Little is known about the outcomes of patients undergoing combined pancreatic and hepatic resections for this indication.

Methods

Patients who underwent hepatectomy for metastatic pNETs at Mayo Clinic Rochester from 2000 to 2020 were retrospectively reviewed. Major pancreatectomy was defined as pancreaticoduodenectomy or total pancreatectomy, and major hepatectomy as right hepatectomy or trisegmentectomy. Characteristics and outcomes of patients who underwent pancreatectomy with simultaneous hepatectomy were compared with those of patients who underwent isolated hepatectomy (with or without prior history of pancreatectomy).

Results

205 patients who underwent hepatectomy for metastatic pNETs were identified: 131 underwent pancreatectomy with simultaneous hepatectomy and 74 underwent isolated hepatectomy. Among patients undergoing simultaneous hepatectomy, 89 patients underwent minor pancreatectomy with minor hepatectomy, 11 patients underwent major pancreatectomy with minor hepatectomy, 30 patients underwent minor pancreatectomy with major hepatectomy, and 1 patient underwent major pancreatectomy with major hepatectomy. Patients undergoing simultaneous hepatectomy had more numerous liver lesions (10 or more lesions in 54% vs. 34%, p = 0.008), but the groups were otherwise similar. Rates of any major complications (31% versus 24%, p = 0.43), hepatectomy-specific complications such as bile leak, hemorrhage, and liver failure (0.8–7.6% vs. 1.4–12%, p = 0.30–0.99), and 90-day mortality (1.5% vs. 2.7%, p = 0.62) were similar between the two groups. 5-year overall survival was 64% after combined resections and 65% after isolated hepatectomy (p = 0.93).

Conclusion

For patients with metastatic pNETs, combined pancreatic and hepatic resections can be performed with acceptable morbidity and mortality in selected patients at high-volume institutions.

Necrolytic migratory erythema is an important visual cutaneous clue of glucagonoma

Glucagonoma is an extremely rare neuroendocrine tumor that arises from pancreatic islet alpha cells. Although glucagonoma is usually accompanied by a variety of characteristic clinical symptoms, early diagnosis is still difficult due to the scarcity of the disease. In this study, we present the cumulative experiences, clinical characteristics and treatments of seven patients diagnosed with glucagonoma during the past 10 years at the First Affiliated Hospital of Xi'an Jiaotong University. The seven patients in our cohort consisted of six females and one male with an average diagnosis age of 40.1 years (range 23-51). The average time from onset of symptoms to diagnosis of glucagonoma was 14 months (range 2-36 months). All the patients visited dermatology first for necrolytic migratory erythema (NME) 7/7 (100%), and other presenting symptoms included diabetes mellitus (DM) 4/7 (57%), stomatitis 2/7 (28%), weight loss 4/7 (57%), anemia 4/7 (57%), diarrhea 1/7 (14%), and DVT1/7 (14%). Plasma glucagon levels were increased in all patients (range 216.92-3155 pg/mL) and declined after surgery. Imaging studies revealed that four of seven patients had liver metastasis. Six of seven patients received surgical resection, and all of them received somatostatin analog therapy. Symptoms improved significantly in 6 out of 7 patients. Three of seven patients died of this disease by the time of follow-up. Our data suggest that if persistent NME is associated with DM and high glucagon levels, timely abdominal imaging should be performed to confirm glucagonoma. Once diagnosed, surgery and somatostatin analogs are effective for symptom relief and tumor control.

Simultaneous Resection of Pancreatic Neuroendocrine Tumors with Synchronous Liver Metastases: Safety and Oncological Efficacy

Simple Summary

Up to half of all newly diagnosed pancreatic neuroendocrine tumors (PNET) present with liver metastases (LM). The surgical resection of PNETs and LMs can provide complete tumor clearance and improve long-term survival. However, the combination of liver and pancreatic resection simultaneously can theoretically cumulate the morbidity and mortality of two separate operations. In the current study, we analyzed the outcomes of the synchronous surgical resection of PNETs and LMs in 51 patients. There were no differences in the postoperative outcomes in terms of mortality and morbidity according to the type of pancreatic resection. The tumor grade was identified as the sole prognostic factor for survival. The resection of well-differentiated PNETs with LMs was characterized by the longest survival rates (median overall survival 128 months, 5-year overall survival 83%). The optimal sequential surgical strategies for PNETs with LM and the use of neoadjuvant/adjuvant chemotherapy in this category of patients remain to be further investigated.

Abstract

Whether the simultaneous resection of pancreatic neuroendocrine tumors (PNET) with synchronous liver metastases (LM) is safe and oncologically efficacious remains to be debated. We retrospectively reviewed clinical data from patients who underwent the simultaneous resection of PNETs with LMs over the last 25 years. Fifty-one consecutive patients with a median age of 54 years (range 27–80 years) underwent pancreaticoduodenectomy (PD) (n = 16), distal pancreatosplenectomy (DSP) (n = 32) or total pancreatectomy (n = 3) with synchronous LM resection. There were no differences in the postoperative outcomes in term of mortality (p = 0.33) and morbidity (p = 0.76) between PD and DSP. The median overall survival (OS) was 64.78 months (95% CI: 49.7–119.8), and the overall survival rates at 1, 3, and 5 years were 97.9%, 86.2% and 61%, respectively. The OS varied according to the tumor grade (G): G1 (OS 128 months, 5-year OS 83%) vs. G2 (OS 60.5 months, 5-year OS 58%) vs. G3 (OS 49.7 months, 5-year OS 0%) (p = 0.03). Multivariate Cox analysis identified G as the only prognostic factor (HR: 5.56; 95% CI: 0.91–9.60; p = 0.01). Simultaneous PNETS with LMs can be performed safely with acceptable morbidity and mortality at tertiary centers. Well-differentiated PNETs had longer survival and might benefit the most from these extended surgeries.

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.

Updated Principles of Surgical Management of Pancreatic Neuroendocrine Tumours (pNETs): What Every Surgeon Needs to Know

Simple Summary

In this narrative review, we update the surgical management of pancreatic neuroendocrine tumours (pNETs) and highlight key elements in view of the recent literature. These tumours are rare and suffer from a lack of data and randomized controlled trials. The pNETs management is difficult due to their heterogeneity and the risks associated with pancreatic surgery. Innovative managements such as “watch and wait” strategies, parenchymal sparing surgery and minimally invasive approach are emerging. The correct use of all these therapeutic options requires a good selection of patients but also a constant update of knowledge.

Abstract

Pancreatic neuroendocrine tumours (pNETs) represent 1 to 2% of all pancreatic neoplasm with an increasing incidence. They have a varied clinical, biological and radiological presentation, depending on whether they are sporadic or genetic in origin, whether they are functional or non-functional, and whether there is a single or multiple lesions. These pNETs are often diagnosed at an advanced stage with locoregional lymph nodes invasion or distant metastases. In most cases, the gold standard curative treatment is surgical resection of the pancreatic tumour, but the postoperative complications and functional consequences are not negligible. Thus, these patients should be managed in specialised high-volume centres with multidisciplinary discussion involving surgeons, oncologists, radiologists and pathologists. Innovative managements such as “watch and wait” strategies, parenchymal sparing surgery and minimally invasive approach are emerging. The correct use of all these therapeutic options requires a good selection of patients but also a constant update of knowledge. The aim of this work is to update the surgical management of pNETs and to highlight key elements in view of the recent literature.

Role of Resection of the Primary in Metastatic Well-Differentiated Neuroendocrine Tumors

OBJECTIVE

Resection of the primary (RP) in metastatic neuroendocrine tumor (NET) is controversial. The aim was to evaluate survival outcomes for RP in metastatic NET patients.

METHODS

Data were obtained from US hospitals at the National Cancer Database between 2004 and 2014. χ2, analysis of variance tests, univariate, and multivariate cox proportional hazards models were evaluated. Kaplan-Meier curves and log-rank tests conducted to compare the survival difference of patient characteristics.

RESULTS

A total of 2361 patients were identified. The mean age was 62.1 years (standard deviation, 13 years), male-to-female ratio 1:1; 33% were small intestine, 26.3% pancreas, and 24.4% lung; 69.6% were well-differentiated; and 42.5% underwent RP. The 5-year overall survival (OS) was significantly improved for patients who underwent RP in small intestine (5-year OS, 63.9% vs 44.2%), lung (5-year OS, 65.4% vs 20.2%), and pancreas tumors (5-year OS, 75.6% vs 30.6%). On multivariate analysis, RP (hazard ratio, 0.46; 95% confidence interval, 0.29-0.73; P < 0.001), female, year of diagnosis 2010-2014, margin, Charlson-Deyo score less than 2, and age less than 51 years, were associated with better OS.

CONCLUSIONS

Resection of the primary in metastatic well-differentiated NET is associated with improved OS compared with no RP.

Current Role of Surgery in Pancreatic Cancer With Synchronous Liver Metastasis

Pancreatic cancer with synchronous liver metastasis has an extremely poor prognosis, and surgery is not recommended for such patients by the current guidelines. However, an increasing body of studies have shown that concurrent resection of pancreatic cancer and liver metastasis is not only technically feasible but also beneficial to the survival in the selected patients. In this review, we aim to summarize the short- and long-term outcomes following synchronous liver metastasectomy for pancreatic cancer patients, and discuss the potential criteria in selecting appropriate surgical candidates, which might be helpful in clinical decision-making.

How to Manage Small Intestine (Jejunal and Ileal) Neuroendocrine Neoplasms Presenting with Liver Metastases?

PURPOSE OF REVIEW

Small intestinal neuroendocrine neoplasms (siNENs) are slowly growing tumours with a low malignant potential. However, more than half of the patients present with distant metastases (stage IV) and nearly all with locoregional lymph node (LN) metastases at the time of surgery. The value of locoregional treatment is discussed controversially.

RECENT FINDINGS

In stage I to III disease, locoregional surgery was currently shown to be curative prolonging survival. In stage IV disease, surgery may prolong survival in selected patients with the chance to cure locoregional disease besides radical/debulking liver surgery. It may improve the quality of life and may prevent severe local complications resulting in a state of chronic malnutrition and severe intestinal ischaemia or bowel obstruction. Locoregional tumour resection offers the opportunity to be curative or to focus therapeutically on liver metastasis, facilitating various other therapeutic modalities. Risks and benefits of the surgical intervention need to be balanced individually.

Outcomes of Simultaneous Resection of Small Bowel Neuroendocrine Tumors with Synchronous Liver Metastases

BACKGROUND

This study evaluated the short- and long-term outcomes of synchronous resection of liver metastases (LM) from small bowel neuroendocrine tumors (SB-NET).

METHODS

A retrospective review of patients undergoing resection for LMs from SB-NETs from January 1997 and December 2018 was performed.

RESULTS

There were 44 patients with synchronous SB-NET and LMs. Perioperative and 90-day mortality values were zero, and the morbidity rate was 27%. The median overall survival (OS) was 128.4 months (CI 95% 74.0-161.5 months) with 1-, 3-, 5-, and 10-year survival rates of 100%, 83%, 79%, and 60%, respectively. Not achieving surgical treatment for LM was the unique independent factor for survival (HR 6.50; CI 95% 1.54-27.28; p = 0.01) in patients with unresected LMs having OS and 10-year survival rates (42 months, 33%) versus patients undergoing liver resection (152 months, 66%)(p = 0.0008). The recurrence rate was 81.8% and associated with longer OS and 5-year survival rates when limited to the liver [223 months (61%) vs 94 months (87%)].

CONCLUSIONS

Simultaneous resection of SB-NETs with synchronous LMs was safe and associated with considerable long-term survival even in the presence of bilobar disease. However, recurrence after resection was common (81%) but associated with longer survival rates when limited to the liver.

Currently available treatment options for neuroendocrine liver metastases

Neuroendocrine neoplasms (NEN) are frequently characterized by a high propensity for metastasis to the liver, which appears to be a dominant site of distant-stage disease, affecting quality of life and overall survival. Liver surgery with the intention to cure is the treatment of choice for resectable neuroendocrine liver metastases (NELM), aiming to potentially prolong survival and ameliorate hormonal symptoms refractory to medical control. Surgical resection is indicated for patients with NELM from well-differentiated NEN, while its feasibility and complexity are largely dictated by the degree of liver involvement. As a result of advances in surgical techniques over the past decades, complex 1- and 2-stage, or repeat liver resections are performed safely and effectively by experienced surgeons. Furthermore, liver transplantation for the treatment of NELM should be anchored in a multimodal and multidisciplinary therapeutic strategy and restricted only to highly selected individual cases. A broad spectrum of interventional radiology treatments for NELM have recently been available, with expanding indications that are more applicable, as they are less limited by patient- and tumor-related parameters, being therefore important adjuncts or alternatives to surgery. Overall, liver-targeted treatment modalities may precede the administration of systemic molecular targeted agents and chemotherapy for patients with liver-dominant metastatic disease; these appear to be a crucial component of multimodal management of patients with NEN. In the present review, we discuss surgical and non-surgical liver-targeted treatment approaches for NELM, each complementing the other, with a view to assisting physicians in optimizing multimodal NEN patient care.

Examining Perioperative Risk Associated with Simultaneous Resection of Primary Neuroendocrine Tumors and Synchronous Hepatic Metastases

BACKGROUND

Surgical debulking of primary neuroendocrine tumors (NETs) and hepatic resection of metastatic NET disease may each independently improve overall survival. However, evidence for combined primary site debulking and metastasectomy on survival and impact on short-term perioperative outcomes is limited.

METHODS

The 2014-2016 ACS-NSQIP targeted hepatectomy database was queried for all patients undergoing liver resection for metastatic NET. Secondary procedure codes were evaluated for major concurrent operations. Multivariable analysis was performed to determine risk factors for 30-day morbidity and mortality.

RESULTS

A total of 472 patients were identified, of whom 153 (32.4%) underwent ≥1 additional concurrent major operation. The most common concurrent procedures were small bowel resection (14.6%), partial colectomy (8.9%), and radical lymphadenectomy (7.4%). Among all patients, overall 30-day mortality and morbidity were 1.5% and 25.6%, respectively. Modifiable and treatment-related factors associated with increased major postoperative morbidity risk included >10% weight loss within six months of surgery (p = 0.05), increasing number of hepatic lesions treated (p = 0.05), and biliary reconstruction (p = 0.001). No major concurrent procedure was associated with increased 30-day morbidity (all p > 0.05).

CONCLUSIONS

Approximately one-third of patients with stage IV NET underwent combined hepatic and multi-organ resection. Although modifiable and treatment-related factors predictive of perioperative morbidity were identified, performance of concurrent major procedures did not increase perioperative morbidity. These results support consideration of multi-organ resection in carefully selected patients with metastatic NET.

Systemic Treatment Selection for Patients with Advanced Pancreatic Neuroendocrine Tumours (PanNETs)

Pancreatic neuroendocrine tumours (PanNETs) are rare diseases and a good example of how research is not only feasible, but also of crucial importance in the scenario of rare tumours. Many clinical trials have been performed over the past two decades expanding therapeutic options for patients with advanced PanNETs. Adequate management relies on optimal selection of treatment, which may be challenging for clinicians due to the fact that multiple options of therapy are currently available. A number of therapies already exist, which are supported by data from phase III studies, including somatostatin analogues and targeted therapies (sunitinib and everolimus). In addition, chemotherapy remains an option, with temozolomide and capecitabine being one of the most popular doublets to use. Peptide receptor radionuclide therapy was successfully implemented in patients with well-differentiated gastro-entero-pancreatic neuroendocrine tumours, but with certain questions waiting to be solved for the management of PanNETs. Finally, the role of immunotherapy is still poorly understood. In this review, the data supporting current systemic treatment options for locally advanced or metastatic PanNETs are summarized. Strategies for treatment selection in patients with PanNETs based on patient, disease, or drug characteristics is provided, as well as a summary of current evidence on prognostic and predictive biomarkers. Future perspectives are discussed, focusing on current and forthcoming challenges and unmet needs of patients with these rare tumours.

Complications of surgery for gastro-entero-pancreatic neuroendocrine neoplasias

Purpose

Surgery is recommended for most patients with gastro-entero-pancreatic neuroendocrine neoplasias (GEP-NENs). Rates of complications and perioperative mortality have been reported in few mostly retrospective single-center series, but there has been no detailed analysis on risk factors for perioperative complications and mortality to date.

Methods

Data of patients with GEP-NENs operated between January 2015 and September 2018 were retrieved from EUROCRINE©, a European online endocrine surgical quality registry, and analyzed regarding rate and risk factors of surgical complications. Risk factors were assessed by logistic regression.

Results

Some 376 patients (211 female, 167 male; age median 63, range 15–89 years) were included. Most NENs were located in the small intestine (SI) (n = 132) or pancreas (n = 111), the rest in the stomach (n = 34), duodenum (n = 30), appendix (n = 30), colon, and rectum (n = 22), or with unknown primary (n = 15). Of the tumors, 320 (85.1%) were well or moderately differentiated, and 147 (39.1%) of the patients had distant metastases at the time of operation. Severe complications (Dindo-Clavien ≥ 3) occurred in 56 (14.9%) patients, and 4 (1.1%) patients died perioperatively. Severe complications were more frequent in surgery for duodenopancreatic NENs (n = 31; 22.0%) compared with SI-NENs (n = 15; 11.4%) (p = 0.014), in patients with lymph node metastases operated with curative aim of surgery (n = 24; 21.4%) versus non-metastasized tumors or palliative surgery (n = 32; 12.1%) (p = 0.020), and in functioning tumors (n = 20; 23.0%) versus non-functioning tumors (n = 30; 13.5%) (p = 0.042). Complication rates were not significantly associated with tumor stage or grade.

Conclusions

Severe complications are frequent in GEP-NEN surgery. Besides duodenopancreatic tumor location, curative resection of nodal metastases and functioning tumors are risk factors for complications.

Advances in the Diagnosis and Management of Well-Differentiated Neuroendocrine Neoplasms

Neuroendocrine neoplasms constitute a diverse group of tumors that derive from the sensory and secretory neuroendocrine cells and predominantly arise within the pulmonary and gastrointestinal tracts. The majority of these neoplasms have a well-differentiated grade and are termed neuroendocrine tumors (NETs). This subgroup is characterized by limited proliferation and patients affected by these tumors carry a good to moderate prognosis. A substantial subset of patients presenting with a NET suffer from the consequences of endocrine syndromes as a result of the excessive secretion of amines or peptide hormones, which can impair their quality of life and prognosis. Over the past 15 years, critical developments in tumor grading, diagnostic biomarkers, radionuclide imaging, randomized controlled drug trials, evidence-based guidelines, and superior prognostic outcomes have substantially altered the field of NET care. Here, we review the relevant advances to clinical practice that have significantly upgraded our approach to NET patients, both in diagnostic and in therapeutic options.

Patients with hepatic oligometastatic pancreatic body/tail ductal adenocarcinoma may benefit from synchronous resection

BACKGROUND

Synchronous resection of primary pancreatic ductal adenocarcinoma (PDAC) and liver metastases in highly selective patients is being accepted based on oncology research progress showing safe surgical outcomes with low morbidity and mortality. We also tried to determine patients who would benefit from the operation.

METHODS

From January 2012 to October 2017, 48 patients who underwent synchronous resection of primary PDAC and liver metastases were retrospectively evaluated. Twenty-three of them underwent oligometastatic synchronous resection.

RESULTS

The majority of synchronous resection PDAC patients underwent hepatic wedge resection, and no oligometastatic patient was treated with hemihepatectomy. The median overall survival (OS) of the synchronous resection patients was 7.8 months. Hepatic oligometastatic PDAC patients had a longer OS than that of non-oligometastatic synchronous resection patients, systemic chemotherapy patients and palliative patients (16.1 vs 6.4 months, P = 0.02; 16.1 vs 7.6 months, P = 0.02; 16.1 vs 4.3 months, P < 0.0001; respectively). Further analysis showed that localized pancreatic body/tail PDAC had a better OS in oligometastatic patients than in non-oligometastatic synchronous resection patients (16.8 months vs 7.05 months, P = 0.0004) and systemic chemotherapy patients (16.8 months vs 8 months, P = 0.003).

CONCLUSION

Patients with pancreatic body/tail PDAC with liver oligometastases can benefit from synchronous resection.

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.

Management of Small Bowel Neuroendocrine Tumors

Several important landmark trials have reshaped the landscape of non-surgical management of small bowel neuroendocrine tumors over the last few years, with the confirmation of the antitumor effect of somatostatin analogue therapy in PROMID and CLARINET trials as well as the advent of therapies with significant potential such as mammalian target of rapamycin inhibitor (mTor) everolimus (RADIANT trials) and peptide receptor radionuclide therapy (PRRT) with 177-Lutetium (NETTER-1 trial). This narrative summarizes the recommended management strategies of small bowel neuroendocrine tumors. We review the main evidence behind each recommendation as well as compare and contrast four major guidelines, namely the 2016 Canadian Consensus guidelines, the 2017 North American Neuroendocrine Tumor Society guidelines, the 2018 National Comprehensive Cancer Network guidelines, and the 2016 European Neuroendocrine Tumor Society guidelines. Different clinical situations will be addressed, from loco-regional therapy to metastatic unresectable disease. Carcinoid syndrome, which is mostly managed by somatostatin analogue therapy and the serotonin antagonist telotristat etiprate for refractory diarrhea, as well as neuroendocrine carcinoma will be reviewed. However, several questions remain unanswered, such as the optimal management of neuroendocrine carcinomas or the effect of combining and sequencing of the aforementioned modalities where more randomized controlled trials are needed.

Pancreatic neuroendocrine tumors

PURPOSE OF REVIEW

Pancreatic neuroendocrine tumors (pNETs) are a rare, heterogeneous group of pancreatic neoplasms with a wide range of malignant potential. They may manifest as noninfiltrative, slow-growing tumors, locally invasive masses, or even swiftly metastasizing cancers.

RECENT FINDINGS

In recent years, because of the increasing amount of scientific literature available for pNETs, the classification, prognostic stratification criteria, and available consensus guidelines for diagnosis and therapy have been revised and updated.

SUMMARY

The vast majority of new pNET diagnoses consist of incidentally discovered lesions on cross-sectional imaging. The biologic behavior of pNETs is defined by the grade and stage of the tumor. Surgery is the only curative treatment and it, therefore, represents the first therapeutic choice for any localized pNET; however, recent evidence suggests that patients with small (<2 cm), nonfunctioning G1 tumors can be safely observed.An aggressive surgical approach towards liver metastases is recommended in selected cases, as well as liver-directed therapies for disease control. In the presence of unresectable progressive disease, somatostatin analogs, targeted therapies such as everolimus, peptide receptor radionuclide therapy, and systemic chemotherapy are all useful tools for prolonging survival.

Spleen-preserving distal pancreatectomy and lymphadenectomy for glucagonoma syndrome: A case report

RATIONALE

Glucagonoma is a rare type of functional pancreatic neuroendocrine tumor that is characterized by distinctive clinical manifestations; among these, necrolytic migratory erythema represents the hallmark clinical sign of glucagonoma syndrome and is usually presented as the initial complaint of patients.

PATIENT CONCERNS

A 30-year-old male patient was admitted to our hospital with a complaint of diffuse erythematous ulcerating skin rash for more than 10 months. He also complained of hyperglycemia and a weight loss of 15 kg in those months.

DIAGNOSIS

This patient underwent a contrast-enhanced computed tomography scan which showed a pancreatic body mass measuring approximately 6 cm with low density accompanied by partial calcification in plain scanning images and uneven enhancement in strengthening periods. In addition, laboratory tests indicated elevated fasting blood glucagon (1109 pg/mL, normal range: 50-150 pg/mL) levels. Glucagonoma syndrome was ultimately diagnosed in clinical.

INTERVENTION

Spleen-preserving distal pancreatectomy was conducted and postoperative pathology revealed the presence of glucagonoma.

OUTCOMES

The patient recovered uneventfully with the glucagonoma syndrome disappeared soon after surgery, and the postoperative plasma glucagon decreased to a normal level. Follow-up showed no recurrence for 5 years since the surgery.

LESSONS

The treatment of glucagonoma should be directed according to the stage at which the disease is diagnosed. Surgery is currently the only method available to cure the tumor, although medications are given to patients who present with advanced glucagonoma and who are not candidates for operation. Multidisciplinary therapy and multimodality treatment are advised, although these have been systematically evaluated to a lesser degree.

Surgery Provides Long-Term Survival in Patients with Metastatic Neuroendocrine Tumors Undergoing Resection for Non-Hormonal Symptoms

INTRODUCTION

Patients with metastatic neuroendocrine tumor (NET) often have an indolent disease course yet the outcomes for patients with metastatic NET undergoing surgery for non-hormonal (NH) symptoms of GI obstruction, bleeding, or pain is not known.

METHODS

We identified patients with metastatic gastroenteropancreatic NET who underwent resection from 2000 to 2016 at 8 academic institutions who participated in the US Neuroendocrine Tumor Study Group.

RESULTS

Of 581 patients with metastatic NET to liver (61.3%), lymph nodes (24.1%), lung (2.1%), and bone (2.5%), 332 (57.1%) presented with NH symptoms of pain (n = 223, 67.4%), GI bleeding (n = 54, 16.3%), GI obstruction (n = 49, 14.8%), and biliary obstruction (n = 22, 6.7%). Most patients were undergoing their first operation (85.4%) within 4 weeks of diagnosis. The median overall survival was 110.4 months, and operative intent predicted survival (p < 0.001) with 66.3% undergoing curative resection. Removal of all metastatic disease was associated with the longest median survival (112.5 months) compared to debulking (89.2 months), or palliative resection (50.0 months; p < 0.001). The 1-, 3-, and 12-month mortality was 3.0%, 4.5%, and 9.0%, respectively. Factors associated with 1-year mortality included palliative operations (OR 6.54, p = 0.006), foregut NET (5.62, p = 0.042), major complication (4.91, p = 0.001), and high tumor grade (11.2, p < 0.001). The conditional survival for patients who lived past 1 year was 119 months.

CONCLUSIONS

Patients with metastatic NET and NH symptoms that necessitate surgery have long-term survival, and goals of care should focus on both oncologic and quality of life impact. Surgical intervention remains a critical component of multidisciplinary care of symptomatic patients.

Curative and palliative surgery in patients with neuroendocrine tumors of the gastro-entero-pancreatic (GEP) tract

The incidence of neuroendocrine tumors (NET) increases with age. Lately, the diagnosis of NET was mainly caused by early detection of small NET (<1 cm) in the rectum and stomach, which are depicted by chance during routine and prophylactic endoscopy. Also in patients with large and metastatic pancreatic and intestinal tumors thorough pathologic investigation with use of different immunohistologic markers discovers more neuroendocrine tumors with low differentiation grade (G2-G3) and more neuroendocrine carcinomas (NEC), nowadays, than in former times. While gastric and rectal NET are discovered as small (<1 cm in diameter) and mainly highly differentiated tumors, demonstrating lymph node metastases in less than 10% of the patients, the majority of pancreatic and small bowel NET have already metastasized at the time of diagnosis. This is of clinical importance, since tumor stage and differentiation grade not only influence prognosis but also surgical procedure and may define whether a combination of surgery with systemic biologic therapy, chemotherapy or local cytoreductive procedures may be used. The indication for surgery and the preferred surgical procedure will have to consider personal risk factors of each patient (i.e. general health, additional illnesses, etc.) and tumor specific factors (i.e. tumor stage, grade of differentiation, functional activity, mass and variety of loco regional as well as distant metastases etc.). Together they define, whether radical curative or only palliative surgery can be applied. Altogether surgery is the only cure for locally advanced NET and helps to increase quality of life and overall survival in many patients with metastatic neuroendocrine tumors. The question of cure versus palliative therapy sometimes only can be answered with time, however. Many different aspects and various questions concerning the indication and extent of surgery and the best therapeutic procedure are still unanswered. Therefore, a close multidisciplinary cooperation of colleagues involved in biochemical and localization diagnostics and those active in various treatment areas is warranted to search for the optimal strategy in each individual patient. How far genetic screening impacts survival remains to be seen. Since surgeons do have a central role in the treatment of NET patients, they have to understand the need for integration into such an interdisciplinary team.

Pancreatic neuroendocrine tumor Grade 1 patients followed up without surgery: Case series

Among the three grades of neuroendocrine tumors (NETs), the prognosis for Grade 1 (G1) with surgery is very good. Therefore, we evaluated the prognoses of pancreatic NET (PNET) G1 patients without surgery. A total of 8 patients who were diagnosed with NET G1, with an observation period of more than 6 mo until surgery or without surgery, were recruited. The patients who underwent surgery were ultimately diagnosed using specimens obtained during the surgery, whereas the patients who did not undergo surgery were diagnosed using specimens obtained by endoscopic ultrasonography-guided fine needle aspiration. Overall, we mainly evaluated the observation period and tumor growth. The observation period for the five cases with surgery ranged from 6-80 mo, and tumor growth was observed in one case. In contrast, the observation period for the three cases without surgery ranged from 17-54 mo, and tumor growth was not observed. Therefore, although the first-choice treatment for NETs is surgery, our experience includes certain NET G1 patients who were followed up without surgery.

Management of neuroendocrine carcinomas of the pancreas (WHO G3): A tailored approach between proliferation and morphology

Neuroendocrine carcinomas (NEC) of the pancreas are defined by a mitotic count > 20 mitoses/10 high power fields and/or Ki67 index > 20%, and included all the tumors previously classified as poorly differentiated endocrine carcinomas. These latter are aggressive malignancies with a high propensity for distant metastases and poor prognosis, and they can be further divided into small- and large-cell subtypes. However in the NEC category are included also neuroendocrine tumors with a well differentiated morphology but ki67 index > 20%. This category is associated with better prognosis and does not significantly respond to cisplatin-based chemotherapy, which represents the gold standard therapeutic approach for poorly differentiated NEC. In this review, the differences between well differentiated and poorly differentiated NEC are discussed considering both pathology, imaging features, treatment and prognostic implications. Diagnostic and therapeutic flowcharts are proposed. The need for a revision of current classification system is stressed being well differentiated NEC a more indolent disease compared to poorly differentiated tumors.

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.

Long-term outcomes and prognostic factors in neuroendocrine carcinomas of the pancreas: Morphology matters

BACKGROUND

Limited data are available for pancreatic neuroendocrine carcinomas (NEC) defined by 2010 World Health Organization (WHO) criteria (mitotic count >20 mitoses/10 high-power fields and/or a Ki67 index of >20%), because most studies encompass heterogeneous cohorts of extrapulmonary/gastrointestinal NEC. Our aim was to evaluate the clinicopathologic characteristics, treatment, and prognosis of patients with pancreatic NEC defined by the 2010 WHO criteria.

METHODS

We conducted a retrospective analysis of 59 patients with a histologic diagnosis of NEC between 1990 and 2012. All cases were re-reviewed and classified according to the WHO 2010 classification and the WHO 2000 criteria.

RESULTS

All patients had stage III pancreatic NEC (n = 34; 58%) or IV pancreatic NEC (n = 25; 43%). Overall, 49 (83%) had poorly differentiated (PD) and 10 (17%) had a well-differentiated (WD) morphology. Fifteen patients (26%) were operated with curative intent (R0/R1), and 8 (14%) were R2 resections. Median disease-specific survival (DSS) for the entire cohort was 14 months. Median DSS did not differ between patient not undergoing resection and those undergoing R2 resection (10 vs 12 months; P > .46), but DSS was greater for patients who underwent R0/R1 resection compared with those with no resection/R2 resection (35 vs 11 months; P < .005). WD morphologic NEC had a greater survival than PD ones (43 vs 12 months; P = .004). Performance status, R2 resection/no resection, PD morphologic NEC, and no medical treatment were independent predictors of poor survival.

CONCLUSION

Pancreatic NEC constitute a heterogeneous group of tumors. Although NEC is an aggressive disease, curative resection in localized disease is associated with improved survival. Morphologic WD pancreatic NEC represents a subgroup with what seems to be a markedly improved survival. Within the NEC category, tumor treatment should be individualized considering tumor morphology as well as the other 2010 WHO criteria.

Surgical management of neuroendocrine tumors

During the last decades an increase in the incidence of neuroendocrine tumors (NETs) was observed. Gastroenteropancreatic NETs represent the majority of NETs. Compared with their epithelial counterpart they usually have a more indolent behaviour and surgical resection improves survival. Tumor diameter is one of the main parameter in the decision making process for nonfunctioning forms. Generally, small lesions can be treated conservatively whereas larger tumors should be treated with standard surgical resection and lymphadenectomy. Functioning tumors should be resected regardless the dimension of the lesion. Locally advanced and metastatic disease should be also treated with extended resections, keeping in consideration the grading, size, Ki67, and presence of extra-abdominal disease. In the case of metastases the panel of operative treatment includes resection, ablation, up to liver transplantation.

Surgical Management of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are uncommon tumors with a range of clinical behavior. Some PNETs are associated with symptoms of hormone secretion, with increased systemic levels of insulin, gastrin, glucagon, or other hormones. More commonly, PNETs are nonfunctional, without hormone secretion. Surgical resection is the mainstay of therapy, particularly for localized disease. Surgical therapy must be tailored to tumor and clinical characteristics. Resection may be particularly indicated in the setting of hormone hypersecretion. Small, incidental PNETs are increasingly managed nonoperatively. Surgery may also be indicated in some instances of metastatic disease, if all metastatic foci may be removed.

Pancreatic Neuroendocrine Tumors: an Update

Pancreatic neuroendocrine tumors (pNETs) are rare and comprise only 1-2 % of all pancreatic neoplastic disease. Although the majority of these tumors are sporadic (90 %), pNETs can arise in the setting of several different hereditary genetic syndromes, most commonly multiple endocrine neoplasia type 1 (MEN1). The presentation of pNETs varies widely, with over 60 % having malignant distant disease at the time of initial diagnosis involving the liver or other distant sites. Functioning pNETs represent approximately 10 % of all pNETs, secrete a variety of peptide hormones, and are responsible for several clinical syndromes caused by profound hormonal derangement. Surgery remains the cornerstone of therapy and the only curative approach. It should be pursued for localized disease and for metastatic lesions amenable to resection. Multimodality therapies, including liver-directed therapies and medical therapy, are gaining increasing favor in the treatment of advanced pNETs. Their utility is multifold and spans from ameliorating symptoms of hormonal excess (functional pNETs) to controlling the local and systemic disease burden (non-functional pNETs). The recent introduction of target molecular therapy has promising results especially for the treatment of progressive well-differentiated G1/G2 tumor. In this review, we summarize the current knowledge and give an update on recent advancements made in the therapeutic strategies for pNETs.

Hepato-pancreatectomy: how morbid? Results from the national surgical quality improvement project

BACKGROUND

Simultaneous resection of both the liver and the pancreas carries significant complexity. The objective of this study was to investigate peri-operative outcomes after a synchronous hepatectomy and pancreatectomy (SHP).

METHODS

The American College of Surgeons National Surgical Quality Improvement Project database was queried to identify patients who underwent SHP. Resections were categorized as '< hemihepatectomy', '≥ hemihepatectomy' (hemihepatectomy and trisectionectomy), 'PD' (pancreaticoduodenectomy and total pancreatectomy) and 'distal' (distal pancreatectomy and enucleation).

RESULTS

From 2005 to 2013, 480 patients underwent SHP. Patients were stratified based on the extent of resection: '< hemihepatectomy + distal (n = 224)', '≥ hemihepatectomy + distal' (n = 49), '< hemihepatectomy + PD' (n = 83) and '≥ hemihepatectomy + PD' (n = 24). Although the first three groups had a reasonable and comparable safety profile (morbidity 33-51% and mortality 0-6.6%), the '≥ hemihepatectomy + PD' group was associated with an 87.5% morbidity (organ space infection 58.3%, re-intubation 12.5%, reoperation 25% and septic shock 25%), 8.3% 30-day mortality and 18.2% in-hospital mortality.

CONCLUSIONS

A synchronous hemihepatectomy (or trisectionectomy) with PD remains a highly morbid combination and should be reserved for patients who have undergone extremely cautious selection.

Well-differentiated neuroendocrine neoplasia: relapse-free survival and predictors of recurrence after curative intended resections

BACKGROUND

Resection with curative intention is the cornerstone of treatment in patients with neuroendocrine tumors. A proportion of patients will relapse after R0 resection, but the factors predictive of recurrence are not well understood.

METHODS

A database established 1998 at the University Hospital Marburg was queried for all patients with documented R0 resection. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Uni- and multivariate analyses were performed.

RESULTS

180 patients with a median age of 52 years entered the analysis. We observed 77 recurrences after a median time of 2.9 years. 24% of the recurrences occurred later than 5 years after operation. Median recurrence-free survival of the whole cohort was 101 months. In univariate analysis grade by Ki-67, stage, high lymph node ratio and microangioinvasion were significant predictors of recurrence. On multivariate analysis these parameters were confirmed as independent prognostic parameters with stage and microangioinvasion being the most important predictors.

CONCLUSIONS

After R0 resection of neuroendocrine tumors, postoperative surveillance should be extended to at least 10 years. Patients with distant metastases and microangioinvasion are at high risk of recurrence. Clinical trials of adjuvant treatment protocols are indicated in these patients.

Perspectives on surgical management of neuroendocrine liver metastases

Abstract: 

Neuroendocrine tumors (NETs) commonly metastasize to the liver. Different treatments are available for the management of metastatic NETs. Both primary tumor and metastases can significantly affect the patients’ quality of life and overall survival (OS). Surgical resection is the only chance for cure and should be considered for every patient. For operable patients, current evidence suggests that liver resection is a safe and effective treatment for neuroendocrine liver metastases. High rates of recurrence are reported following resection of neuroendocrine liver metastases. There is no evidence to support incomplete (R2) resection (debulking) surgery to improve OS or quality of life. When surgery is performed for NETs, other conservative adjuvant treatments should also be considered to prolong symptom-free, disease-free and OS.

Liver-directed therapy for neuroendocrine liver metastases

Abstract: 

Neuroendocrine tumors are relatively uncommon neoplasms presenting with a wide spectrum of clinical behavior. Many patients may present with or develop liver metastases from neuroendocrine tumors, which significantly influences prognosis and the potential for symptoms. Data suggest that some patients may have symptomatic relief and oncologic benefit from liver-directed therapy for neuroendocrine tumor metastases. Surgical resection, tumor ablation, transarterial therapy such as bland embolization, chemoembolization and radioembolization, as well as liver transplantation have been studied as liver-directed therapies. Data continue to emerge to help guide selection of treatment modality for an individual patient. The spectrum of behavior of neuroendocrine metastases and heterogeneity in the literature are a challenge to arriving at cohesive recommendations for all patients.

When should a liver resection be performed in patients with liver metastases from neuroendocrine tumours? A systematic review with practice recommendations

AIM

To determine the benefits and risks of hepatic resection versus non-resectional liver-directed treatments in patients with potentially resectable neuroendocrine liver metastases.

METHODS

A systematic review identified 1594 reports which alluded to a possible liver resection for neuroendocrine tumour metastases, of which 38 reports (all retrospective), comprising 3425 patients, were relevant.

RESULTS

Thirty studies reported resection alone, and 16 studies reported overall survival (OS). Only two studies addressed quality-of-life (QoL) issues. Five-year overall survival was reported at 41-100%, whereas 5-year progression-free survival (PFS) was 5-54%. We identified no robust evidence that a liver resection was superior to any other liver-directed therapies in improving OS or PFS. There was no evidence to support the use of a R2 resection (debulking), with or without tumour ablation, to improve either OS or QoL. There was little evidence to guide sequencing of surgery for patients presenting in Stage IV with resectable disease, and none to support a resection of asymptomatic primary tumours in the presence of non-resectable liver metastases.

CONCLUSION

Low-level recommendations are offered to assist in the management of patients with neuroendocrine liver metastases, along with recommendations for future studies.

Long-Term Outcomes of Surgical Management of Pancreatic Neuroendocrine Tumors with Synchronous Liver Metastases

BACKGROUND

The value of surgical resection in the management of pancreatic neuroendocrine tumors (PNET) with liver metastases (LM) is still debated. The aim of this study was to evaluate the outcomes of surgery of PNET with LM.

METHODS

Patients with PNET with synchronous LM between 2000 and 2011 from 4 high-volume institutions were included. The patients were divided into 3 groups: curative resection, palliative resection, and no resection.

RESULTS

Overall, 166 patients were included. Eighteen patients (11%) underwent curative resection, 73 patients (43%) underwent palliative resection, and 75 patients (46%) underwent conservative treatment. The median overall survival (OS) from the time of diagnosis was 73 months. Patients who underwent curative resection had a significantly better median OS from the initial diagnosis compared with those who underwent palliative resection and those who were conservatively treated (97 vs. 89 vs. 36 months, p = 0.0001). The median OS from the time of diagnosis in those patients who underwent radical or palliative resection was 97 months, with a 5-year survival rate of 76%. On multivariate analysis, factors associated with OS from the time of diagnosis were the presence of bilobar metastases, tumor grading, and curative resection in a first model. On a second model, curative or palliative surgery was an independent predictor of OS. Among 91 patients who underwent surgery, the presence of pancreatic neuroendocrine carcinoma G3 was the only factor independently associated with a poorer survival after surgery (median OS: 35 vs. 97 months, p < 0.0001).

CONCLUSIONS

Patients with LM from PNET benefit from surgical resection, although surgery should be reserved to well- or moderately differentiated forms.

Practical management and treatment of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (NETs) are uncommon disease, about which little is known. Pancreatic NETs are usually slow growing and their malignant potential are often underestimated. The management of this disease poses a challenge because of the heterogeneous clinical presentation and varying degrees of aggressiveness. Recently, several guidelines for the management of pancreatic NETs have been established and help to devise clinical strategy. In the treatment algorithms, however, a lot of uncertain points are included. Practical treatment decisions of pancreatic NETs are still sometimes made in a patient- and/or physicians-oriented manner. The tumor grading system proposed by the European Neuroendocrine Tumor Society (ENETS) gives important prognostic information, however, the implication of grading regarding medical treatment strategies to choose has not yet been clarified. Moreover, the place of surgical treatment is unclear in the overall management course of advanced pancreatic NETs. In some cases, practical management and treatment have to be individualized depending on predominant symptoms, tumor spread, and general health of the patients. Current issues and a few points to make a strategy in the management of pancreatic NETs would be reviewed.

Curative versus palliative surgical resection of liver metastases in patients with neuroendocrine tumors: a meta-analysis of observational studies

BACKGROUND

The role of surgical therapy in patients with liver metastases from neuroendocrine tumors (NETs) is unclear. In this study, the results obtained with curative or palliative resection, by reviewing recent literature and performing a meta-analysis, were examined.

MATERIALS AND METHODS

A systematic review and meta-analysis of observational studies published between January 1990 and October 2013 were performed. Studies that evaluated the different survival between patients treated by curative or palliative surgical resection of hepatic metastases from NETs were considered. The collected studies were evaluated for heterogeneity, publication bias, and quality. To calculate the pooled hazard ratio (HR) estimate and the 95% confidence interval (95% CI), a fixed-effects model was applied.

RESULTS

After the literature search, 2,546 studies were found and, among 38 potentially eligible studies, 3 were considered. We did not find a significant longer survival in patients treated with curative surgical resection of hepatic metastases when compared to palliative hepatic resection HR 0.40 (95% CI: 0.14-1.11). In one study, palliative resection of hepatic metastases significantly increased survival when compared to embolization.

CONCLUSIONS

Curative and also palliative surgery of NETs liver metastases may improve survival outcome. However, further randomized clinical trials are needed to elucidate this argument.

Update on pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (pNETs) are relatively rare tumors comprising 1-2% of all pancreas neoplasms. In the last 10 years our understanding of this disease has increased dramatically allowing for advancements in the treatment of pNETs. Surgical excision remains the primary therapy for localized tumors and only potential for cure. New surgical techniques using laparoscopic approaches to complex pancreatic resections are a major advancement in surgical therapy and increasingly possible. With early detection being less common, most patients present with metastatic disease. Management of these patients requires multidisciplinary care combining the best of surgery, chemotherapy and other targeted therapies. In addition to surgical advances, recently, there have been significant advances in systemic therapy and targeted molecular therapy.

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.

Elevated Ki-67 labeling index in 'synchronous liver metastases' of well differentiated enteropancreatic neuroendocrine tumor

There is no consensus as to whether or not metastatic nodules in the liver should be biopsied for tumor grading in cases of neuroendocrine tumors with 'synchronous liver metastasis'. In this study, we compared the Ki-67 labeling index between the primary tumor and synchronous liver metastasis in 30 patients, who had received simultaneous resections. Examined tumors were of the small bowel (n = 18) or pancreas (n = 12), and G1 or G2 in primary histologic grade. In 20 patients (67%), the Ki-67 index was similar between the primary tumor and liver metastasis, but 10 (33%) showed an elevation of 3.4-14.4% in the liver, which increased the tumor grade in 4 cases. The Ki-67 elevation in the liver was more common in G2 than G1 neoplasms (P = 0.002). The size, but not number, of liver metastases was significantly larger in patients with an elevated Ki-67 index (P = 0.006). Using 40 mm as a provisional cutoff for the greatest diameter of liver metastases, the positive predictive value of this discriminator for elevated Ki-67 was 56%, and the negative predictive value was 93%. In conclusion, synchronous liver metastases can yield a higher Ki-67 labeling index than primary neuroendocrine tumours, particularly when the secondary is greater than 40 mm.

Safety and outcome of combined liver and pancreatic resections

Background

In Western countries, combined liver and pancreatic resections (CLPR) are performed rarely because of the perceived high morbidity and mortality rates. This study evaluated the safety and outcomes of CLPR at a tertiary European centre for hepatopancreatobiliary surgery.

Methods

A review of two prospectively maintained databases for pancreatic and liver resections was undertaken to identify patients undergoing CLPR between January 1994 and January 2012. Clinicopathological and surgical outcomes were analysed. Univariable and multivariable analyses for postoperative morbidity were performed.

Results

Fifty consecutive patients with a median age of 58 (range 20–81) years underwent CLPR. Indications for surgery were neuroendocrine carcinoma (16 patients), biliary cancer (15), colonic cancer (5), duodenal cancer (1) and others (13). The type of pancreatic resection included pancreaticoduodenectomy (30), distal pancreatectomy (17), spleen-preserving distal pancreatectomy (2) and total pancreatectomy (1). Twenty-three patients had associated major hepatectomies, 27 underwent minor liver resections and 11 had associated vascular resections. Mortality and morbidity rates were 4 and 46 per cent respectively. Univariable and multivariable analysis showed no differences in postoperative morbidity in relation to extent of liver resection or type of pancreatic resection. Use of preoperative chemotherapy was the only independent risk factor associated with postoperative morbidity (P = 0·021).

Conclusion

CLPR can be performed with fairly low morbidity and mortality rates. Postoperative outcomes were not affected by the extent of liver resection or the type of pancreatic resection. Patients receiving chemotherapy should be evaluated carefully before surgery is considered.