Treatment of liver metastases from neuroendocrine tumours in relation to the extent of hepatic disease

Liver Tumor Burden in Pancreatic Neuroendocrine Tumors: CT Features and Texture Analysis in the Prediction of Tumor Grade and 18F-FDG Uptake

Pancreatic neuroendocrine tumors (p-NETs) are a rare group of neoplasms that often present with liver metastases. Histological characteristics, metabolic behavior, and liver tumor burden (LTB) are important prognostic factors. In this study, the usefulness of texture analysis of liver metastases in evaluating the biological aggressiveness of p-NETs was assessed. Fifty-six patients with liver metastases from p-NET were retrospectively enrolled. Qualitative and quantitative CT features of LTB were evaluated. Histogram-derived parameters of liver metastases were calculated and correlated with the tumor grade (G) and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) standardized uptake value (SUV). Arterial relative enhancement was inversely related with G (−0.37, p = 0.006). Different metastatic spread patterns of LTB were not associated with histological grade. Arterial_entropy was significantly correlated to G (−0.368, p = 0.038) and to Ki67 percentage (−0.421, p = 0.018). The ROC curve for the Arterial_entropy reported an area under the curve (AUC) of 0.736 (95% confidence interval 0.545–0.928, p = 0.035) in the identification of G1–2 tumors. Arterial_uniformity values were correlated to G (0.346, p = 0.005) and Ki67 levels (0.383, p = 0.033). Arterial_entropy values were directly correlated with the SUV (0.449, p = 0.047) which was inversely correlated with Arterial_uniformity (−0.499, p = 0.025). Skewness and kurtosis reported no significant correlations. In conclusion, histogram-derived parameters may predict adverse histological features and metabolic behavior of p-NET liver metastases.

Long-term outcome of surgical resection in patients with gastroenteropancreatic neuroendocrine neoplasia: results from a German nation-wide multi-centric registry

BACKGROUND

Neuroendocrine neoplasia (NEN) are rare and heterogenous tumours. Few data exist on the impact of surgical therapy.

MATERIALS AND METHODS

This is a retrospective analysis of prospectively collected data of gastroenteropancreatic NEN in the German NET-Registry (1999-2012). It focuses on patients without distant metastases (limited disease, LD, stage I-IIIB).

RESULTS

Data of 2239 patients with NEN were recorded. Median age was 59 years, the gender ratio was 1:1.3 (f:m). A total of 986 patients (44%) had LD, and the 5-year survival rate (5 years) was 77% for all and 90% for patients with LD. A total of 1635 patients (73%) received a surgical therapy (1st to 6th line); the 5 and 10 ysr were 83/65% after and 59/35% without surgery for all patients (p < .001). The resection margins in the LD patients were 76%, 16%, and 3% for R0, R1 and R2, respectively. The 10 ysr was 84%, 59% and 42% for R0, R1 and R2 resections, respectively (p = .021 R0/R1, p < .001 R0/R2). The R0 resection rate was 75% for G1/G2 NET and 67% for G3 NEC.

CONCLUSION

The rate of complete tumour resection (R0) in LD is independent of tumour grading, and R0 resection is the key determinant of long-term survival, as demonstrated by the 10 ysr. of 84%. All NEN patients with limited disease should be considered for operation, if possible, as the best 10-year survival is shown after an R0 resection.

ALPPS in neuroendocrine liver metastases not amenable for conventional resection - lessons learned from an interim analysis of the International ALPPS Registry

BACKGROUND

Surgery is the most effective treatment option for neuroendocrine liver metastases (NELM). This study investigated the role of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) as a novel strategy in treatment of NELM.

METHODS

The International ALPPS Registry was reviewed to study patients who underwent ALPPS for NELM.

RESULTS

From 2010 to 2017, 954 ALPPS procedures from 135 international centers were recorded in the International ALPPS Registry. Of them, 24 (2.5%) were performed for NELM. Twenty-one patients entered the final analysis. Overall grade ≥3b morbidity was 9% after stage 1 and 27% after stage 2. Ninety-day mortality was 5%. R0 resection was achieved in 19 cases (90%) at stage 2. Median follow-up was 28 (19-48) months. Median disease free survival (DFS) was 17.3 (95% CI: 7.1-27.4) months, 1-year and 2-year DFS was 73.2% and 41.8%, respectively. Median overall survival (OS) was not reached. One-year and 2-year OS was 95.2% and 95.2%, respectively.

CONCLUSIONS

ALPPS appears to be a suitable strategy for inclusion in the multimodal armamentarium of well-selected patients with neuroendocrine liver metastases. In light of the morbidity in this initial series and a high rate of disease-recurrence, the procedure should be taken with caution.

Patient Selection and Toxicities of PRRT for Metastatic Neuroendocrine Tumors and Research Opportunities

OPINION STATEMENT

Neuroendocrine tumors (NETs) are a heterogenous group of neoplasms characterized by varied biological hallmarks and behavior, ranging from indolent to aggressive. For many decades, somatostatin analogues and few targeted therapies were available for NETs and these therapies had minimal response rates. However, there have been a number of recent treatment advances. Peptide receptor radionuclide therapy (PRRT) is a novel approach to treatment of NETs and has changed the landscape of treatment for NETs. It is a form of targeted therapy in which a radiolabeled somatostatin analogue delivers radiation specifically to tumor cells expressing the somatostatin receptor.

Liver metastases in gastroenteropancreatic neuroendocrine tumours - treatment methods

Surgical approaches that allow the safe treatment of multiple, bilateral, large tumours, and that combine extirpative, ablative and interventional therapies, have expanded the population of patients with neuroendocrine tumors (NET) liver metastases (LMs) who can benefit from aggressive treatment of their liver disease. Pre-treatment staging often includes the biochemical assessment of serologic markers such as serotonin, insulin, vasoactive intestinal peptide, and chromogranin, even in patients without clinically apparent hormonal excess. Radiofrequency ablation (RFA) is a technique that involves the use of thermal energy to induce coagulation necrosis, thereby destroying tumour cells. Resection plus RFA is increasingly used in patients with bilateral NET LMs. Resection is performed for large or dominant lesions, while ablation is used to treat small lesions. Hepatic arterial embolization, typically termed transarterial embolization, and transarterial chemoembolization have been shown to induce a reduction in tumour size and to ameliorate symptoms of excess hormonal secretion.

Quantitative Pretreatment CT Parameters as Predictors of Tumor Response of Neuroendocrine Tumor Liver Metastasis to Transcatheter Arterial Bland Embolization

PURPOSE

To assess whether parameters on preprocedural CT can be utilized to predict the response of NETLM to transcatheter arterial bland embolization (TAE).

METHODS

We retrospectively reviewed 135 target lesions from 48 NETLM patients who underwent TAE and with complete preprocedural multiphasic CT. Parameters on preprocedural CT including the longest diameter, mean attenuation value in nonenhanced, arterial, and portal-venous phases were collected from each target lesion. Radiological responses were assessed according to RECIST 1.1. The parameters of responder lesions and nonresponder lesions were compared. Arterial enhancement index (AEI) and portal-venous enhancement index (PEI) were calculated. The predictive function of AEI and PEI on tumor response was analyzed by receiver operating characteristic (ROC) curve.

RESULTS

A total of 72.6% target lesions had a partial response. For patients, the objective response rate was 72.9%. Mean attenuation values of responder lesions were significantly higher than nonresponder lesions in both arterial and portal-venous phases (105.36 ± 37.24 vs. 76.01 ± 19.19, p < 0.001; 96.61 ± 24.04 vs. 82.12 ± 21.37, p = 0.002). ROC curve showed that both AEI and PEI were effective in predicting tumor response (area under the curve [AUC] 0.757, p < 0.001; AUC 0.655, p = 0.005).

CONCLUSION

AEI and PEI, parameters from evaluation of CT pretreatment attenuation of NETLMs, could predict response to TAE treatment.

Neuroendocrine Neoplasms of the Small Bowel and Pancreas

The traditionally promulgated perspectives of neuroendocrine neoplasms (NEN) as rare, indolent tumours are blunt and have been outdated for the last 2 decades. Clear increments in their incidence over the past decades render them increasingly clinically relevant, and at initial diagnosis many present with nodal and/or distant metastases (notably hepatic). The molecular pathogenesis of these tumours is increasingly yet incompletely understood. Those arising from the small bowel (SB) or pancreas typically occur sporadically; the latter may occur within the context of hereditary tumour predisposition syndromes. NENs can also be associated with endocrinopathy of hormonal hypersecretion. Tangible advances in the development of novel biomarkers, functional imaging modalities and therapy are especially applicable to this sub-set of tumours. The management of SB and pancreatic neuroendocrine tumours (NET) may be challenging, and often comprises a multidisciplinary approach wherein surgical, medical, interventional radiological and radiotherapeutic modalities are implemented. This review provides a comprehensive overview of the epidemiology, pathophysiology, diagnosis and treatment of SB and pancreatic NETs. Moreover, we provide an outlook of the future in these tumour types which will include the development of precision oncology frameworks for individualised therapy, multi-analyte predictive biomarkers, artificial intelligence-derived clinical decision support tools and elucidation of the role of the microbiome in NEN development and clinical behaviour.

Nonconventional Doses of Somatostatin Analogs in Patients With Progressing Well-Differentiated Neuroendocrine Tumor

PURPOSE

To evaluate the antiproliferative activity and safety of nonconventional high doses of somatostatin analogs (HD-SSA) in patients with well-differentiated gastroenteropancreatic (GEP) neuroendocrine tumors (NET) with radiological disease progression according to Response Evaluation Criteria in Solid Tumors (RECIST) criteria on a previous treatment.

METHODS

A retrospective analysis of prospectively maintained databases from 13 Italian NET-dedicated centers was performed. Main inclusion criteria were: well-differentiated G1 or G2 GEP-NET, progressive disease on a previous treatment, and subsequent treatment with HD-SSA (either by increased administered dose [dose intensity] or shortened interval between administrations [dose density]). Main endpoints were progression-free survival (PFS) and safety.

RESULTS

Of 198 patients, 140 matched inclusion criteria and were included in the analysis. Overall, median PFS was 31 months. Use of HD-SSA as second-line treatment was associated with reduced risk for progression or death compared with third- or further-line treatment (HR: 2.12; P = 0.004). There was no difference in PFS between HD-SSA by increased dose density (N = 133; 95%) or intensity (N = 7; 5%). Partial response according to RECIST criteria was observed in 12 patients (8.6%), and stable disease was achieved in 106 (75.7%) patients. Adverse events occurred in 21 patients (15.0%), 2 of whom had grade 3 biliary stone disease. No patients discontinued HD-SSA treatment due to adverse events.

CONCLUSIONS

HD-SSA is an active and safe treatment option in patients with progressive well-differentiated GEP-NET. The high rate of objective responses observed deserves prospective validation in ad hoc clinical trials.

The prognostic analysis of different metastatic patterns in pancreatic neuroendocrine tumors patients: A population based analysis

OBJECTIVE

To evaluate the prognostic value of pancreatic neuroendocrine tumors (pNETs) with different metastatic patterns.

METHODS

Data of pNETs cases were extracted from the Surveillance, Epidemiology, and End Result (SEER) database. They were classified according to the different metastatic patterns. We utilized chi-square test to compare the clinical and metastasis characteristics among different groups. We used Kaplan-Meier analysis and log-rank testing for survival comparisons. Adjusted HRs with 95% CIs was calculated using Cox regression model to estimate prognostic factors. P < .05 was considered statistically significant.

RESULTS

Among the 3909 patients, liver is the most metastatic organ, and isolated brain metastasis is the least common. At the same time, many patients have had multiple metastases. We studied the overall survival (OS) and cancer-specific survival (CCS) of the groups. OS: Non-organ metastasis: 5-year OS = 77.1%; Bone metastasis: median survival time (MST) = 56 m, 5-year OS = 42.7%; Liver metastasis: MST = 24 m, 5-year OS = 25.5%; Lung metastasis: MST = 14 m, 5-year OS = 33.7%; multiple metastases: MST = 7m, 5-year OS = 12.0%. CCS: Non-organ metastasis: 5-year OS = 84.2%; Bone metastasis: 5-year OS = 52.5%; Liver metastasis: MST = 27 m, 5-year OS = 28.6%; Lung metastasis: MST = 49 m, 5-year OS = 40.1%; multiple metastases: MST = 8 m, 5-year OS = 14.5%. In addition, the results showed that there were all statistical significances between the surgery and the no surgery group (all, P < .001). Multivariate analysis revealed that brain metastasis, multiple metastases, age over 60 years, unmarried, grade III/IV, regional/distant and no surgery were independently associated with decreased OS and CCS.

CONCLUSIONS

pNETs patients without organ metastasis had the best survival outcomes, while multiple had the worst outcomes. There were no significant differences in bone metastasis, liver metastasis and lung metastasis. Surgery was still an option for patients with metastasis.

Radioembolization with 90Y Resin Microspheres of Neuroendocrine Liver Metastases After Initial Peptide Receptor Radionuclide Therapy

Purpose

Peptide receptor radionuclide therapy (PRRT) and radioembolization are increasingly used in neuroendocrine neoplasms patients. However, concerns have been raised on cumulative hepatotoxicity. The aim of this sub-analysis was to investigate hepatotoxicity of yttrium-90 resin microspheres radioembolization in patients who were previously treated with PRRT.

Methods

Patients treated with radioembolization after systemic radionuclide treatment were retrospectively analysed. Imaging response according to response evaluation criteria in solid tumours (RECIST) v1.1 and clinical response after 3 months were collected. Clinical, biochemical and haematological toxicities according to common terminology criteria for adverse events (CTCAE) v4.03 were also collected. Specifics on prior PRRT, subsequent radioembolization treatments, treatments after radioembolization and overall survival (OS) were collected.

Results

Forty-four patients were included, who underwent a total of 58 radioembolization procedures, of which 55% whole liver treatments, at a median of 353 days after prior PRRT. According to RECIST 1.1, an objective response rate of 16% and disease control rate of 91% were found after 3 months. Clinical response was seen in 65% (15/23) of symptomatic patients after 3 months. Within 3 months, clinical toxicities occurred in 26%. Biochemical and haematological toxicities CTCAE grade 3–4 occurred in ≤ 10%, apart from lymphocytopenia (42%). Radioembolization-related complications occurred in 5% and fatal radioembolization-induced liver disease in 2% (one patient). A median OS of 3.5 years [95% confidence interval 1.8–5.1 years] after radioembolization for the entire study population was found.

Conclusion

Radioembolization after systemic radionuclide treatments is safe, and the occurrence of radioembolization-induced liver disease is rare.

Level of Evidence

4, case series.

Prognostic factors influencing survival in small bowel neuroendocrine tumor with liver metastases

BACKGROUND

Resection of liver metastasis in small bowel neuroendocrine tumors (SBNET) may improve survival, however, factors influencing prognosis are unclear. We evaluated how the extent of resection influences outcomes.

METHODS

Patients with SBNET with liver metastasis from 1990 to 2013 who underwent resection of the primary tumor were identified. Outcomes among patients undergoing complete resection (CR), partial resection (PR), or no resection (NR) of liver metastases with resection of the primary tumor only were compared.

RESULTS

One hundred eleven patients met the criteria. The median number of liver lesions was seven and median lesions resected was one. Fifty (45%) patients had NR, 41 (36.9%) underwent CR, and 20 (18.1%) underwent PR. The 5-year overall survival (OS) was 79.4% for NR, 84.7% for PR, and 100% for CR, demonstrating a trend that CR was best, followed by PR then NR (P = .02). 10-year OS showed no significant differences (72.7% NR; 84.7% PR; 82.5% CR; P = .10). Greater than 10 liver lesions (hazard ratio [HR] 3.6; P = 0.04) or receiving chemotherapy (HR 3.7; P = .03) were negative predictors of survival.

CONCLUSION

The extent of resection of liver disease in SBNET influenced survival at 5 years but not at 10 years. In addition, more than 10 liver lesions and chemotherapy were predictors of mortality.

Diagnostic and Management Challenges in Vasoactive Intestinal Peptide Secreting Tumors: A Series of 15 Patients

OBJECTIVES

Vasoactive intestinal peptide-secreting tumors (VIPomas) are rare functioning neuroendocrine tumors often characterized by a difficult-to-control secretory syndrome and high potential to develop metastases. We hereby present the characteristics of 15 cases of VIPomas and provide a recent literature review.

METHODS

This was a retrospective data analysis of 15 patients with VIPoma from 3 different centers and literature research through PubMed database during the last 10 years.

RESULTS

Fifteen patients with VIPomas (9 with hepatic metastases at diagnosis) with watery diarrhea and raised VIP levels were studied. Ten patients (67%) had grade 2 tumors, 6 of 15 had localized disease and underwent potentially curative surgery, whereas the remaining 9 received multiple systemic therapies; 3 patients died during follow-up. The median overall survival was 71 months (range, 41-154 months). Patients who were treated with curative surgery (n = 7) had longer median overall survival compared with patients who were treated with other therapeutic modalities (44 vs 33 months).

CONCLUSIONS

The management of VIPomas is challenging requiring the application of multiple treatment modalities. Patients who underwent surgical treatment with curative intent appear to have higher survival rate. Central registration and larger prospective studies are required to evaluate the effect of currently employed therapies in these patients.

Radioembolisation with 90Y microspheres for neuroendocrine liver metastases: an institutional case series, systematic review and meta-analysis

BACKGROUND

Neuroendocrine liver metastases are clinically challenging due to their frequent disseminated distribution. This study aims to present a British experience with an emerging modality, radioembolisation with yttrium-90 labelled microspheres, and embed this within a meta-analysis of response and survival outcomes.

METHODS

A retrospective case series of patients treated with SIR-Spheres (radiolabelled resin microspheres) was performed. Results were included in a systematic review and meta-analysis of published results with glass or resin microspheres. Objective response rate (ORR) was defined as complete or partial response. Disease control rate (DCR) was defined as complete/partial response or stable disease.

RESULTS

Twenty-four patients were identified. ORR and DCR in the institutional series was 14/24 and 21/24 at 3 months. Overall survival and progression-free survival at 3-years was 77.6% and 50.4%, respectively. There were no grade 3/4 toxicities post-procedure. A fixed-effects pooled estimate of ORR of 51% (95% CI: 47%-54%) was identified from meta-analysis of 27 studies. The fixed-effects weighted average DCR was 88% (95% CI: 85%-90%, 27 studies).

CONCLUSION

Current data demonstrate evidence of the clinical effectiveness and safety of radioembolisation for neuroendocrine liver metastases. Prospective randomised studies to compare radioembolisation with other liver directed treatment modalities are needed.

Macrovascular venous invasion of pancreatic neuroendocrine tumours: impact on surgical outcomes and survival

BACKGROUND

This study evaluates the impact of macrovascular venous invasion (MVI) on surgical and survival outcomes of pancreatic neuroendocrine tumours (PNETs).

METHODS

We retrospectively reviewed data of 125 patients operated for PNETs. Operative, pathological,and survival outcomes were compared between PNETs with and without MVI.

RESULTS

Macrovascular venous invasion was detected in 25 of 125 PNETs (20%) presenting as tumour thrombi (n = 12) or venous wall invasion (n = 13). MVI was associated with larger tumours, a higher rate of lymph node involvement, less differentiated tumours, and a higher rate of perineural invasion. Resection of PNETS with MVI more often necessitated combined hepatic, venous and multivisceral resections, had a higher rate of intraoperative blood transfusion (p = 0.04) but similar morbidity (44% vs. 42%) and mortality (0 vs. 1%) as PNETs without MVI. PNETs with MVI had a lower median overall survival rate (60 vs. 149 months; p = 0.03). Multivariate analysis revealed that PNETs of the pancreatic head, synchronous liver metastases and higher tumour grade were prognostic factors for overall survival.

CONCLUSIONS

MVI is found in more advanced PNETs. Resection of PNETs with MVI is characterized by increased transfusion rate and reduced overall survival.

Liver Resection for Neuroendocrine Tumor Liver Metastases Within Milan Criteria for Liver Transplantation

BACKGROUND

The role of liver transplant (LT) for neuroendocrine liver metastasis (NELM) has not been completely defined. While international guidelines included LT as a potential treatment for highly selected patients with advanced NELM, recently, LT has been proposed as an alternative curative treatment for NELM for patients meeting restrictive criteria (Milan criteria).

METHODS

Using a multi-institutional cohort of patients undergoing liver resection for NELM, the long-term outcomes of patients meeting Milan criteria (resected NET drained by the portal system, stable disease/response to therapies for at least 6 months, metastatic diffusion to < 50% of the total liver volume, a confirmed histology of low-grade, and ≤ 60 years) were investigated.

RESULTS

Among the 238 patients included in the study, 28 (12%) patients met the Milan criteria for LT with a 5-year OS of 83%. Furthermore, among patients meeting Milan criteria, subsets of patients with favorable clinic-pathological characteristics had 5-year OS rates greater than 90% including G1 patients (5-year OS, 92%), patients undergoing minor liver resection (5-year OS, 94%), patients with low number of NELM (1-2 NELM), and small tumor size (< 3 cm) (for both groups of patients, 5-year OS, 100%).

CONCLUSIONS

In our series, only 12% of patients met Milan criteria, and the 5-year OS after liver resection for this small selected group of patients was comparable with that reported in the literature for patients undergoing LT for NELM within Milan criteria. While LT might be the optimal treatment for patients with unresectable NELM, surgical resection should be the first option for patients with resectable NELM.

Activity and Safety of Standard and Prolonged Capecitabine/Temozolomide Administration in Patients with Advanced Neuroendocrine Neoplasms

BACKGROUND

Capecitabine and temozolomide combination (CAPTEM) is associated with high response rates in patients with advanced neuroendocrine neoplasms (NENs). We evaluated the real-world activity and safety of CAPTEM from 3 NEN centers.

METHODS

Clinicopathological characteristics and outcomes of patients treated with CAPTEM for bulky or progressive disease (PD) were retrospectively analyzed. -Results: Seventy-nine patients with gastroenteropancreatic (grades 1-2 [n = 38], grade 3 [n = 24]) and lung/thymic (n = 17) NENs were included. Median treatment duration was 12.1 months (range 0.6-55.6). Overall, partial responses (PRs) occurred in 23 (29.1%), stable (SD) in 24 (30.4%), and PD in 28 (35.4%) patients. Median progression-free survival (PFS) and overall survival (OS) were 10.1 (6-14.2) and 102.9 months (43.3-162.5), respectively. On univariate analysis, NENs naive to chemotherapy and low Ki67 were associated with favorable responses (partial response [PR] + SD; p = 0.011 and 0.045), PFS (p < 0.0001 and 0.002) and OS (p = 0.005 and 0.001). Primary site (pancreas and lung/thymus) was also a significant prognostic factor for PFS (p < 0.0001) and OS (p < 0.0001). On multivariate analysis, gastrointestinal and unknown primary NENs (hazard ratio [HR] 0.3, 95% CI 0.1-0.8, p = 0.009 and p = 0.018) and prior surgery (HR 2.4, 95% CI 11-4.9, p = 0.021) were independent prognostic factors for PFS. Ki-67 was a poor predictor for favorable response in receiver operating characteristic analysis (area under the curve 0.678). Safety analysis of CAPTEM indicated rare events of serious (grades 3-4) toxicities (n = 4) and low discontinuation rates (n = 8) even in patients with prolonged administration (>12 months).

CONCLUSIONS

CAPTEM treatment can be an effective and safe treatment even after prolonged administration for patients with NENs of various sites and Ki67 labeling index, associated with significant favorable responses and PFS.

Sporadic pancreatic neuroendocrine tumor: Surgery of the primary tumor

The management of patients with sporadic pancreatic neuroendocrine tumors (PNET) is multi-disciplinary and often, multimodal. Surgery has a large part in treatment because it is the only potentially curative therapeutic modality if resection can be complete. The update reviews the operative indications and the different surgical techniques available (including parenchymal-sparing surgery) to treat the primary lesion according to patient status, preoperative work-up and whether the tumor is functioning or not. The place of observation for "small" non-functional sporadic PNET is also discussed.

Surgical Approaches to the Management of Neuroendocrine Liver Metastases

Surgical approaches to hepatic metastases occupy an important role in the management of patients with neuroendocrine neoplasms and may have curative or palliative intentions. Resection of hepatic disease with curative intent is the only modality offering potential cure for patients with liver metastases; however, only a minority of patients are eligible. Regardless of resection margin, disease recurrence almost invariably occurs and novel adjuvant/neoadjuvant therapies are mandated to be included within multimodal treatment concepts. Liver transplantation in meticulously selected patients may be associated with excellent outcomes, but unfortunately demands on donated organs limit the wider utilization of this approach.

Treatment options for PNET liver metastases: a systematic review

BACKGROUND

Pancreatic neuroendocrine tumors (PNETs) are rare pancreatic neoplasms. About 40-80% of patients with PNET are metastatic at presentation, usually involving the liver (40-93%). Liver metastasis represents the most significant prognostic factor. The aim of this study is to present an up-to-date review of treatment options for patients with liver metastases from PNETs.

METHODS

A systematic literature search was performed using the PubMed database to identify all pertinent studies published up to May 2018.

RESULTS

The literature search evaluated all the therapeutic options for patients with liver metastases of PNETs, including surgical treatment, loco-regional therapies, and pharmacological treatment. All the different treatment options showed particular indications in different presentations of liver metastases of PNET. Surgery remains the only potentially curative therapeutic option in patients with PNETs and resectable liver metastases, even if relapse rates are high. Efficacy of medical treatment has increased with advances in targeted therapies, such as everolimus and sunitinib, and the introduction of radiolabeled somatostatin analogs. Several techniques for loco-regional control of metastases are available, including chemo- or radioembolization.

CONCLUSIONS

Treatment of patients with PNET metastases should be multidisciplinary and must be personalized according to the features of individual patients and tumors.

Liver transplantation and multivisceral transplantation in the management of patients with advanced neuroendocrine tumours

Orthotopic liver transplantation (OLT) represents a generally accepted albeit somewhat controversially discussed therapeutic strategy in highly selected patients with non-resectable hepatic metastases from neuroendocrine tumours (NET). Whilst there are some exclusion criteria, these are not universally followed, and the optimal set of inclusion parameters for deeming patients eligible has not yet been elucidated. This is due to heterogeneity in the study populations, as well differing approaches employed and also divergences in selection criteria between centres. Recent data have suggested that OLT may represent the most efficacious approach in terms of overall and disease-free survival to the management of NET metastatic to the liver when conducted in accordance with the modified Milan criteria. Therefore, a consensus set of selection criteria requires definition to facilitate stringent and fair allocation of deceased-donor organs, as well as consideration for living-donor organs. In the context of classically non-resectable metastatic tumour bulk, multivisceral transplantation with or without the liver may also be indicated, yet experience is very limited. In this review, we discuss the diagnostic work-up of patients in whom the aforementioned transplantation approaches are being considered, critically analyse the published experience and also anticipate future developments in this field, including a discussion of immediate and longer-term research priorities.

Multimodality Management of "Borderline Resectable" Pancreatic Neuroendocrine Tumors: Report of a Single-Institution Experience

Background:

Pancreatic neuroendocrine tumors (PanNETs) constitute approximately 3% of pancreatic neoplasms. Like patients with pancreatic ductal adenocarcinoma (PDAC), some of these patients present with “borderline resectable disease.” For these patients, an optimal treatment approach is lacking. We report our institution’s experience with borderline resectable PanNETs using multimodality treatment.

Methods:

We identified patients with borderline resectable PanNETs who had received neoadjuvant therapy at our institution between 2000 and 2013. The definition of borderline resectability was based on National Comprehensive Cancer Network criteria for PDAC. Neoadjuvant regimen, radiographic response, pathologic response, surgical margins, nodal retrieval, number of positive nodes, and recurrence were documented. Statistics were descriptive.

Results:

Of 112 patients who underwent surgical resection for PanNETs during the study period, 23 received neoadjuvant therapy, 6 of whom met all inclusion criteria and had borderline resectable disease. These 6 patients received at least 1 cycle of temozolomide and capecitabine, with 3 also receiving radiation. All had radiographic evidence of treatment response. Four (67%) had negative-margin resections. Four patients had histologic evidence of a moderate response. Follow-up (3.0-4.3 years) indicated that all patients were alive, with 5/6 free of disease (1 patient with metastatic disease still on treatment without progression).

Conclusions:

A multimodality treatment strategy (neoadjuvant temozolomide and capecitabine ± radiation) can be successfully applied to patients with PanNETs who meet NCCN borderline resectable criteria for PDAC. To our knowledge, this is the first report of the use of a multimodality protocol in the treatment of patients with borderline resectable PanNETs.

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.

Preoperative imaging and pathologic classification for pancreatic neuroendocrine tumors

The management of patients with pancreatic neuroendocrine tumor (PNET), whether hormonally secretory or not, is multidisciplinary and often multimodal. Surgical treatment plays a central role because complete resection is the only potentially curative treatment. The choice of the therapeutic plan for a PNET requires precise localization of the primary tumor (which may sometimes be multiple in case of genetic predisposition), confirmation of the diagnosis of PNET, a search for metastases (mainly hepatic), and identification of the main histoprognostic factors. This update focuses on the WHO 2017 histological classification and recent innovations in the preoperative assessment of PNET using conventional and isotopic imaging. The aim is to not only allow the mapping of primary and metastatic lesions but also to predict tumor aggressiveness.

Peptide receptor radionuclide therapy as neoadjuvant therapy for resectable or potentially resectable pancreatic neuroendocrine neoplasms

BACKGROUND

Peptide receptor radionuclide therapy is a valid therapeutic option for pancreatic neuroendocrine neoplasms. The aim of this study was to describe an initial experience with the use of peptide receptor radionuclide therapy as a neoadjuvant agent for resectable or potentially resectable pancreatic neuroendocrine neoplasms.

METHODS

The postoperative outcomes of 23 patients with resectable or potentially resectable pancreatic neuroendocrine neoplasms at high risk of recurrence who underwent neoadjuvant peptide receptor radionuclide therapy (peptide receptor radionuclide therapy group) were compared with 23 patients who underwent upfront surgical operation (upfront surgery group). Patients were matched for tumor size, grade, and stage. Median follow-up was 61 months.

RESULTS

The size (median greatest width) of the primary pancreatic neuroendocrine neoplasms decreased after neoadjuvant peptide receptor radionuclide therapy (59 to 50 mm; P=.047). There were no differences in intraoperative and postoperative outcomes and there were no operative deaths, but the risk of developing a pancreatic fistula tended to be less in the peptide receptor radionuclide therapy group when compared to the upfront surgery group (0/23 vs 4/23; P < .02). The incidence of nodal metastases at the time of resection was also less in the peptide receptor radionuclide therapy group (n= 9/23 vs 17/23; P<.02). Neither median disease-specific survival (not reached in either group; P=.411) nor progression-free survival (52 vs 37 months; P>.2) differed between groups, but progression-free survival in the 31 patients who had an R0 resection seemed to be greater in the 15 patients in the peptide receptor radionuclide therapy group versus 16 patients the upfront group (median progression-free survival not reached vs 36 months; P<.05).

CONCLUSION

Neoadjuvant peptide receptor radionuclide therapy for resectable or potentially resectable pancreatic neuroendocrine neoplasms in patients with high-risk features of recurrence seems to be beneficial, but well-designed and much larger prospective trials are needed to confirm the safety and the oncologic value of this approach.

The place of liver transplantation in the treatment of hepatic metastases from neuroendocrine tumors: Pros and cons

Liver metastases occur in nearly half of NET patients (MNETs) and heavily affect prognosis, with 5-yr. OS around 19-38%. Although it is difficult to show outcome differences for available treatments, due to the long course of disease, surgery for MNETs remains the most effective option in terms of survival and symptom control. Since MNETs frequently present as an oligo-metastatic, liver-limited disease, unresectable in 80% of cases, liver transplantation (LT) has emerged as a potential curative treatment. Nevertheless, experience with LT for MNETs is limited and burdened by highly heterogeneous outcomes and significant recurrence rate, mostly explained by the variability of selection criteria. Several prognostic factors have been identified: extended surgery on primary tumor associated to LT, elderly patients, pancreatic primary (pNET), extensive liver involvement, poorly differentiated tumors, high Ki67 levels and short wait time to LT. A proper patients' selection based on these data (Milan NET criteria) allows a significant survival advantage over non-transplant strategies, with excellent outcomes in recent series (69-97.2% 5-yr. OS) as opposed to patients undergoing non-surgical treatments (34-50.9%). Evidence indicates LT as the best option for selected patients with MNETs. The use of organs for MNETs is therefore justified.

Is there any role for minimally invasive surgery in NET?

Neuroendocrine tumors (NET) represent the variability of almost benign lesions either secreting hormones occurring as a single lesion up to malignant lesions with metastatic potential. Treatment of NET is usually performed by surgical resection. Due to the rarity of NET, surgical treatment is mainly based on the experience and recommendations of experts and less on the basis of prospective randomized studies. In addition, the development and establishment of new surgical procedures is made more difficult by their rarity. The development of laparoscopic-assisted surgery has significantly improved the treatment of many diseases. Due to the well-known advantages of laparoscopic surgery, this method has also been increasingly used to treat NET. However, due to limited comparative data, the assumed superiority of laparoscopic surgery in the area NET remains often unclear or not yet proven. This review focuses on the present usage of laparoscopic techniques in the area of NET. Relating to the current literature, this review presents the evidence of various laparoscopic procedures for treatment of adrenal, pancreatic and intestine NET as well as extraadrenal pheochromocytoma and neuroendocrine liver metastases. Further, this review focuses on recent new developments of minimally invasive surgery in the area of NET. Here, robotic-assisted surgery and single-port surgery are promising approaches.

Single-institution experience of radioembolization with yttrium-90 microspheres for unresectable metastatic neuroendocrine liver tumors

BACKGROUND AND AIM

The aim of this study was to assess the effectiveness of yttrium-90 (⁹⁰ Y) microspheres for the treatment of unresectable metastatic liver neuroendocrine tumors (NET).

METHODS

From February 2006 to September 2015, 36 patients (19 male and 17 female, age 63.6 ± 9.4 years) who underwent ⁹⁰ Y therapy for unresectable liver metastases of NET were included and analyzed retrospectively. All patients received a variety of treatments before ⁹⁰ Y therapy. The radiological response, symptoms improvement of carcinoid syndrome, tumor marker changes, complications, side effects/toxicity, survival, and factors related to survival were evaluated and analyzed.

RESULTS

Of the 36 patients, the mean delivered dose of ⁹⁰ Y was 1.8 ± 0.7 GBq with a total of 40 treatments. Overall disease control rate was 88.9% (32/36) at 3 months following therapy. In 16 patients with carcinoid syndrome, 15 (93.8%) patients had symptomatic improvement. Tumor marker response (5-hydroxyindoleacetic acid [n = 7] and chromogranin A [n = 13]) at 3 months after treatment were as follows: none (n = 0, 4), partial (n = 6, 7), and complete (n = 1, 2). Radiation-induced gastrointestinal ulcers (n = 2, 5.6%) were identified. Side effects included fatigue (n = 31, 86.1%), anorexia (n = 26, 72.2%), nausea (n = 15, 41.7%), vomiting (n = 14, 38.9%), abdominal pain (n = 10, 27.8%), and fever (n = 8, 22.2%). The mean follow-up was 27.0 ± 16.4 months, with a median survival of 41.0 months. Child-Pugh classification (P = 0.008) and lymph node metastases (P = 0.045) had statistically significant influence on overall survival.

CONCLUSIONS

Yttrium-90 radioembolization can be effective in the treatment of unresectable liver metastases of NET who failed to respond to other treatments.

The Surgical Management of Small Bowel Neuroendocrine Tumors: Consensus Guidelines of the North American Neuroendocrine Tumor Society

Small bowel neuroendocrine tumors (SBNETs) have been increasing in frequency over the past decades, and are now the most common type of small bowel tumor. Consequently, general surgeons and surgical oncologists are seeing more patients with SBNETs in their practices than ever before. The management of these patients is often complex, owing to their secretion of hormones, frequent presentation with advanced disease, and difficulties with making the diagnosis of SBNETs. Despite these issues, even patients with advanced disease can have long-term survival. There are a number of scenarios which commonly arise in SBNET patients where it is difficult to determine the optimal management from the published data. To address these challenges for clinicians, a consensus conference was held assembling experts in the field to review and discuss the available literature and patterns of practice pertaining to specific management issues. This paper summarizes the important elements from these studies and the recommendations of the group for these questions regarding the management of SBNET patients.

Is there still a role for the hepatic locoregional treatment of metastatic neuroendocrine tumors in the era of systemic targeted therapies?

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) frequently present with distant metastases at the time of diagnosis and the liver is the most frequent site of spreading. The early identification of metastatic disease represents a major prognostic factor for GEP-NENs patients. Radical surgical resection, which is feasible for a minority of patients, is considered the only curative option, while the best management for patients with unresectable liver metastases is still being debated. In the last few years, a number of locoregional and systemic treatments has become available for GEP-NEN patients metastatic to the liver. However, to date only a few prospective studies have compared those therapies and the optimal management option is based on clinical judgement. Additionally, locoregional treatments appear feasible and safe for disease control for patients with limited liver involvement and effective in symptoms control for patients with diffuse liver metastases. Considering the lack of randomized controlled trials comparing the locoregional treatments of liver metastatic NEN patients, clinical judgment remains key to set the most appropriate therapeutic pathway. Prospective data may ultimately lead to more personalized and optimized treatments. The present review analyzes all the locoregional therapy modalities (i.e., surgery, ablative treatments and transarterial approach) and aims to provide clinicians with a useful algorithm to best treat GEP-NEN patients metastatic to the liver.

Resection of liver metastasis from neuroendocrine tumors: evaluation of results and prognostic factors

OBJECTIVES

to determine the prognostic factors that may impact on morbidity and mortality and survival of patients undergoing surgical treatment of liver metastases from neuroendocrine tumors.

METHODS

We studied 22 patients undergoing liver resection for metastases from neuroendocrine tumors between 1997 and 2007. Epidemiological and clinical data were correlated with morbidity and mortality and overall and disease-free survivals.

RESULTS

twelve patients were male and ten female, with a mean age of 48.5 years. Bilobar disease was present in 17 patients (77.3%). In ten patients (45.5%) the primary tumor originated in the pancreas, terminal ileum in eight, duodenum in two, rectum in one and jejunum in one. Complete surgical resection (R0) was achieved in 59.1% of patients. Eight patients (36.3%) developed complications in the immediate postoperative period, one of them dying from septicemia. All patients undergoing re-hepatectomy and/or two-stage hepatectomy had complications in the postoperative period. The overall survival at one and five years was 77.3% and 44.2%. The disease-free survival at five years was 13.6%. The primary pancreatic neuroendocrine tumor (p = 0.006) was associated with reduced overall survival. Patients with number of metastatic nodules < 10 (p = 0.03) and asymptomatic at diagnosis (p = 0.015) had higher disease-free survival.

CONCLUSION

liver metastases originating from pancreatic neuroendocrine tumors proved to be a negative prognostic factor. Symptomatic patients with multiple metastatic nodules showed a significant reduction in disease-free survival.

Neuroendocrine, goblet cell and mixed adeno-neuroendocrine tumours of the appendix: updates, clinical applications and the future

Appendiceal neuroendocrine neoplasms are rare, clinically challenging tumours that are typically incidentally diagnosed, have a poorly understood biology and have controversy surrounding their management. Most are adequately treated with appendectomy, and although distant metastases are rare, the threat of disease dissemination remains and current guidelines possess poor accuracy in terms of selecting patients requiring more extensive surgery, i.e. oncological right-hemicolectomy. Areas covered: In this article, we discuss the presentation and diagnostic work-up of patients with appendiceal neuroendocrine neoplasms, and also examine the evidence base for existing management strategies. We highlight controversies within the management of these tumours, and anticipate avenues for further progress. Although no longer classified as neuroendocrine neoplasms, we also discuss two related forms of tumours with neuroendocrine features - goblet cell cancers and mixed adeno-neuroendocrine carcinomas. Expert commentary: Existing guidelines for the treatment of appendiceal neuroendocrine neoplasms are derived from a limited evidence base and are unable to accurately predict which patients require extensive attempts at surgical disease control. Future advances in the field of improved patient selection for more extensive surgery may be possible with multi-factorial tumour assessment integrating morphological and molecular analyses.

A Novel Nomogram to Predict the Prognosis of Patients Undergoing Liver Resection for Neuroendocrine Liver Metastasis: an Analysis of the Italian Neuroendocrine Liver Metastasis Database

Even though surgery remains the only potentially curative option for patients with neuroendocrine liver metastases, the factors determining a patient's prognosis following hepatectomy are poorly understood. Using a multicentric database including patients who underwent hepatectomy for NELMs at seven tertiary referral hepato-biliary-pancreatic centers between January 1990 and December 2014, we sought to identify the predictors of survival and develop a clinical tool to predict patient's prognosis after liver resection for NELMs. The median age of the 238 patients included in the study was 61.9 years (interquartile range 51.5-70.1) and 55.9 % (n = 133) of patients were men. The number of NELMs (hazard ratio = 1.05), tumor size (HR = 1.01), and Ki-67 index (HR = 1.07) were the predictors of overall survival. These variables were used to develop a nomogram able to predict survival. According to the predicted 5-year OS, patients were divided into three different risk classes: 19.3, 55.5, and 25.2 % of patients were in low (>80 % predicted 5-year OS), medium (40-80 % predicted 5-year OS), and high (<40 % predicted 5-year OS) risk classes. The 10-year OS was 97.0, 55.9, and 20.0 % in the low, medium, and high-risk classes, respectively (p < 0.001). We developed a novel nomogram that accurately (c-index >70 %) staged and predicted the prognosis of patients undergoing liver resection for NELMs.

Imaging Biomarkers of Tumor Response in Neuroendocrine Liver Metastases Treated with Transarterial Chemoembolization: Can Enhancing Tumor Burden of the Whole Liver Help Predict Patient Survival?

Purpose To investigate whether whole-liver enhancing tumor burden [ETB] can serve as an imaging biomarker and help predict survival better than World Health Organization (WHO), Response Evaluation Criteria in Solid Tumors (RECIST), modified RECIST (mRECIST), and European Association for the Study of the Liver (EASL) methods in patients with multifocal, bilobar neuroendocrine liver metastases (NELM) after the first transarterial chemoembolization (TACE) procedure. Materials and Methods This HIPAA-compliant, institutional review board-approved retrospective study included 51 patients (mean age, 57.8 years ± 13.2; range, 13.5-85.8 years) with multifocal, bilobar NELM treated with TACE. The largest area (WHO), longest diameter (RECIST), longest enhancing diameter (mRECIST), largest enhancing area (EASL), and largest enhancing volume (ETB) were measured at baseline and after the first TACE on contrast material-enhanced magnetic resonance images. With three-dimensional software, ETB was measured as more than 2 standard deviations the signal intensity of a region of interest in normal liver. Response was assessed with WHO, RECIST, mRECIST, and EASL methods according to their respective criteria. For ETB response, a decrease in enhancement of at least 30%, 50%, and 65% was analyzed by using the Akaike information criterion. Survival analysis included Kaplan-Meier curves and Cox regressions. Results Treatment response occurred in 5.9% (WHO criteria), 2.0% (RECIST), 25.5% (mRECIST), and 23.5% (EASL criteria) of patients. With 30%, 50%, and 65% cutoffs, ETB response was seen in 60.8%, 39.2%, and 21.6% of patients, respectively, and was the only biomarker associated with a survival difference between responders and nonresponders (45.0 months vs 10.0 months, 84.3 months vs 16.7 months, and 85.2 months vs 21.2 months, respectively; P < .01 for all). The 50% cutoff provided the best survival model (hazard ratio [HR]: 0.2; 95% confidence interval [CI]: 0.1, 0.4). At multivariate analysis, ETB response was an independent predictor of survival (HR: 0.2; 95% CI: 0.1, 0.6). Conclusion Volumetric ETB is an early treatment response biomarker and surrogate for survival in patients with multifocal, bilobar NELM after the first TACE procedure. ^© RSNA, 2016.

The Long-Term Benefit of Liver Transplantation for Hepatic Metastases From Neuroendocrine Tumors

Selection criteria and benefit of liver transplantation for hepatic metastases from neuroendocrine tumors (NETs) remain uncertain. Eighty-eight consecutive patients with metastatic NETs eligible for liver transplantation according to Milan-NET criteria were offered transplant (n = 42) versus nontransplant options (n = 46) depending on list dynamics, patient disposition, and age. Tumor burden between groups did not differ. Transplant patients were younger (40.5 vs. 55.5 years; p < 0.001). Long-term outcomes were compared after matching between groups made on multiple Cox models adjusted for propensity score built on logistic models. Survival benefit was the difference in mean survival between transplant versus nontransplant options. No patients were lost or died without recurrence. Median follow-up was 122 months. The transplant group showed a significant advantage over nontransplant strategies at 5 and 10 years in survival (97.2% and 88.8% vs. 50.9% and 22.4%, respectively; p < 0.001) and time-to-progression (13.1% and 13.1% vs. 83.5% and 89%; p < 0.001). After adjustment for propensity score, survival advantage of the transplant group was significant (hazard ratio = 7.4; 95% confidence interval (CI): 2.4-23.0; p = 0.001). Adjusted transplant-related survival benefit was 6.82 months (95% CI: 1.10-12.54; p = 0.019) and 38.43 months (95% CI: 21.41-55.45; p < 0.001) at 5 and 10 years, respectively. Liver transplantation for metastatic NETs under restrictive criteria provides excellent long-term outcome. Transplant-related survival benefit increases over time and maximizes after 10 years.

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.

Neuroendocrine Tumors

Neuroendocrine tumors are increasingly diagnosed, either incidentally as part of screening processes, or for symptoms, which have commonly been mistaken for other disorders initially. The diagnostic workup to characterize tumor behaviour and prognosis focuses on histologic, anatomic, and functional imaging assessments. Several therapeutic options exist for patients ranging from curative and debulking surgery through to liver-directed therapies and systemic treatments. Multimodal therapies are often required over the patient's disease history. The management paradigm can be complex but should be focused on curative resections and then on controlling symptoms and limiting disease progression. There are several new systemic therapies that have completed phase 3 studies with new compounds being studied in phase 2. Genetic and epigenetic markers may lead to a new era of personalised therapy in the future.

Emergency therapy for liver metastases from advanced VIPoma: surgery or transarterial chemoembolization?

VIPoma is a rare neuroendocrine tumor (NET) with a high potential to develop hepatic metastases and poor prognosis. The primitive tumor is nonsymptomatic and usually localized within the pancreas. Liver metastasis drives the prognosis and induces profuse watery diarrhea or renal failure. We herein present severe renal failure or diarrhea in two patients hospitalized in intensive care justifying emergency treatment of liver metastasis. The two patients experienced severe diarrhea due to a hypersecretion of vasoactive intestinal peptide (VIP) from liver metastasis released into the blood circulation. Therapeutic management was discussed and liver transarterial chemoembolization (TACE) was performed with chemotherapy-loaded embospheres, which cause necrosis of tumor lesions. TACE controlled the hormonal syndrome and made patients eligible for curative surgery. Tumor necrosis occurred and VIP levels collapsed. Surgery was performed in one of the two cases after TACE and the patient was considered in remission. Both patients were still alive after 3 years of follow up. Thus, TACE is feasible and appears to be an effective emergency treatment in patients with a VIP-hormonal syndrome due to liver metastases. Despite the biological disorder due to the hormonal secretion, an aggressive approach is warranted in VIP liver metastasis.

Liver Resection for Non-Colorectal Liver Metastases - Standards and Extended Indications

Background

Due to the uncertain benefit of liver resection for non-colorectal liver metastases (NCLM), patient selection for surgery is generally difficult. Therefore, the aim of this article was to propose standard and extended indications for liver resection in this heterogeneous disease collective.

Methods

Review of the literature.

Results

The myriad of biologically different primary tumor entities as well as the mostly small and retrospective studies investigating the benefit of surgery for NCLM limits the proposal of general recommendations. Only resection of neuroendocrine liver metastases (NELM) appears to offer a clear benefit with a 5- and 10-year overall survival (OS) of 74 and 51%, respectively, in the largest series. Resection of liver metastases from genitourinary primaries might offer reasonable benefit in selected cases – with a 5-year OS of up to 61% for breast cancer and of 38% for renal cell cancer. The long-term outcome following surgery for other entities was remarkably poorer, e.g., gastric cancer, pancreatic cancer, and melanoma reached a 5-year OS of 20-42, 17-25, and about 20%, respectively.

Conclusion

Liver resection for NELM can be defined as a standard indication for the resection of NCLM while lesions of genitourinary origin might be defined as an extended indication.