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

Surgical Management and Long-Term Evaluation of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) arise from neuroendocrine cells and are a rare class of heterogenous tumors with increasing incidence. The diagnosis, staging, treatment, and prognosis of PNETs depend heavily on identifying the histologic features and biological mechanisms. Here, the authors provide an overview of the diagnostic workup (biomarkers and imaging), grade, and staging of PNETs. The authors also explore associated genetic mutations and molecular pathways and describe updated guidelines on surgical and systemic treatment modalities.

Palliative primary tumor resection may not offer survival benefits for patients with unresectable metastatic colorectal neuroendocrine neoplasms, one multicenter retrospective cohort study

BACKGROUND

The efficacy of palliative primary tumor resection (PTR) in improving prognosis for patients with unresectable metastatic colorectal neuroendocrine neoplasms (NENs) has not been fully explored.

METHODS

We performed one retrospective cohort study and recruited 68 patients with unresectable metastatic colorectal NENs from two Chinese medical centers between 2000 and 2022. All patients were assigned to PTR group and no PTR group. The clinicopathological manifestation data were carefully collected, and the survival outcomes were compared between the two groups using Kaplan-Meier methods. Propensity score matching (PSM) was conducted to minimize confounding bias. Univariate and multivariate Cox proportional hazards regression analyses were performed to identify prognostic factors.

RESULTS

A total of 32 patients received PTR, and the other 36 patients did not. The median progression-free survival (PFS) and overall survival (OS) times were 4 and 22 months in the whole cohort, respectively. For patients who received no PTR, the median OS was 16 months, and the 1-year OS rate and 3-year OS rate were 56.4% and 39.6%, respectively. For patients who received PTR, the median OS was 24 months, and the 1-year OS rate and 3-year OS rate were 67.9% and 34.1%, respectively. However, the Kaplan-Meier survival curves and log-rank test demonstrated no significant survival difference between the two groups (P = 0.963). Moreover, palliative PTR was also not confirmed as a prognostic factor in subsequent univariable and multivariable Cox proportional hazards regression analyses in both the original and matched cohorts. Only histological differentiation was identified as an independent prognostic factor affecting PFS [hazard ratio (HR) = 1.86, 95% confidence interval (CI): 1.02-3.41, P = 0.043] and OS [HR = 3.70, 95% CI: 1.09-12.48, P = 0.035] in the original cohort.

CONCLUSIONS

Palliative PTR may not offer survival benefits for patients with unresectable metastatic colorectal NENs.

Impact of primary tumor resection and metastasectomy among gastroentero-pancreatic neuroendocrine tumors with liver metastases only on survival

BACKGROUND

Despite recommendations for primary tumor resection (PTR) with or without liver resection (LR) in the patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) and isolated liver metastases, there are conflicting data for their impact on overall survival (OS).

METHODS

2320 patients with GEP-NETs and isolated liver metastases were identified from NCDB. Multiple imputations were used to accommodate missing data, and inverse probability of treatment weighting (IPTW) was conducted to minimize bias.

RESULTS

Patients with PTR had a greater OS than those without PTR (3-year rate of 88.6% vs. 69.9%, P < 0.001), which was preserved in the adjusted analysis (IPTW-adjusted HR = 0.387, 95% CI: 0.264-0.567; P < 0.001). Patients with LR had a greater OS than those without LR (3-year rate 87.7% vs. 75.2%, P = 0.003), which was also preserved in adjusted analysis (IPTW-adjusted HR = 0.450, 95% CI: 0.229-0.885; P = 0.021). Patients undergoing both PTR and LR had the greatest survival advantage than those with other surgical interventions (P < 0.001).

CONCLUSIONS

Either PTR or LR is associated with improved survival for GEP-NET patients with isolated liver metastases. However, there remains significant selection bias in the current study, and caution should be exercised when selecting patients for resection.

Pancreatic Neuroendocrine Neoplasms Larger than 4 cm: A Retrospective Observational Study of Surgery, Histology, and Outcome

BACKGROUND

Pancreatic neuroendocrine neoplasms (pNENs) are often detected as large primary lesions, even with distant metastases, and their prognosis may be difficult to predict.

METHODS

In this retrospective study, we retrieved data of patients treated for a large pNEN in our Surgical Unit (1979-2017) to evaluate the possible prognostic role of clinic-pathological features and surgery. Cox-proportional hazard regression models were used to find possible associations among some variables (clinical features, surgery, and histology) and survival at univariate and multivariate analyses.

RESULTS

Among 333 pNENs, we identified 64 patients (19%) with a lesion > 4 cm. Patients' median age was 61 years, median tumor size was 6.0 cm, and 35 (55%) patients had distant metastases at diagnosis. There were 50 (78%) nonfunctioning pNENs, and 31 tumors localized in the body/tail region of the pancreas. Overall, 36 patients underwent a standard pancreatic resection (with 13 associated liver resection/ablation). Regarding histology, 67% of pNENs were N1, and 34% were grade 2. After a median follow-up of 48 months (up to 33 years), 42 patients died of disease. Median survival after surgery was 79 months, and six patients experienced recurrence (median DFS 94 months). At multivariate analysis, distant metastases were associated with a worse outcome, while having undergone radical tumor resection was a protective factor.

CONCLUSIONS

In our experience, about 20% of pNENs have a size > 4 cm, 78% are nonfunctioning, and 55% show distant metastases at diagnosis. Nevertheless, a long-term survival of more than five years may be achieved after surgery.

Chronological improvement of pancreatectomy for resectable but advanced pancreatic neuroendocrine neoplasms

BACKGROUND

Progress of non-surgical treatments in the last decade has improved the prognosis of pancreatic neuroendocrine neoplasms (PanNEN). However, the improvement of surgery for advanced PanNEN remains unknown. This study aimed to investigate the chronological changes of the clinical impact of pancreatectomy for PanNEN.

METHODS

Patients undergoing curative-intent pancreatectomy for PanNEN between 1991 and 2010 were categorized into the earlier period group, and those between 2011 and 2021 were into the later period group. Advanced PanNEN was defined as showing resectable synchronous liver metastases or invasion to portal venous systems or adjacent organs. The recurrence-free survival (RFS) and overall survival (OS) were analyzed among patients with non-advanced and advanced PanNENs. The independent prognostic risk factors were identified using a Cox proportional hazard model.

RESULTS

A total of 189 patients (n = 54 in the earlier period and n = 135 in the later period) were included. The proportion of advanced PanNEN increased from 15% to 30% (P = 0.027). The RFS and OS of non-advanced PanNEN were similar between the periods. Whereas, among patients with advanced PanNEN, the later period group showed improved prognosis; The 5-year RFS of the earlier period vs. the later period was 0% vs. 27%, and the 5-year OS was 38% vs. 82% (p = 0.013).

CONCLUSIONS

A radical surgical treatment for advanced PanNEN has shown prognostic improvement in this decade. However, more careful perioperative examinations and possibly, additional treatments are required for PanNEN with portal vein invasion.

Role of surgical treatments in high-grade or advanced gastroenteropancreatic neuroendocrine neoplasms

Over the last 40 years, the incidence and prevalence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have continued to increase. Compared to other epithelial neoplasms in the same organ, GEP-NENs exhibit indolent biological behavior, resulting in more chances to undergo surgery. However, the role of surgery in high-grade or advanced GEP-NENs is still controversial. Surgery is associated with survival improvement of well-differentiated high-grade GEP-NENs, whereas poorly differentiated GEP-NENs that may benefit from resection require careful selection based on Ki67 and other tissue biomarkers. Additionally, surgery also plays an important role in locally advanced and metastatic disease. For locally advanced GEP-NENs, isolated major vascular involvement is no longer an absolute contraindication. In the setting of metastatic GEP-NENs, radical intended surgery is recommended for patients with low-grade and resectable metastases. For unresectable metastatic disease, a variety of surgical approaches, including cytoreduction of liver metastasis, liver transplantation, and surgery after neoadjuvant treatment, show survival benefits. Primary tumor resection in GEP-NENs with unresectable metastatic disease is associated with symptom control, prolonged survival, and improved sensitivity toward systemic therapies. Although there is no established neoadjuvant or adjuvant strategy, increasing attention has been given to this emerging research area. Some studies have reported that neoadjuvant therapy effectively reduces tumor burden, improves the effectiveness of subsequent surgery, and decreases surgical complications.

Surgical Treatment of Patients with Poorly Differentiated Pancreatic Neuroendocrine Carcinoma: An NCDB Analysis

BACKGROUND

Consensus guidelines discourage resection of poorly differentiated pancreatic neuroendocrine carcinoma (panNEC) given its association with poor long-term survival. This study assessed treatment patterns and outcomes for this rare malignancy using the National Cancer Database (NCDB).

METHODS

Patients with non-functional pancreatic neuroendocrine tumors in the NCDB (2004-2016) were categorized based on pathologic differentiation. Logistic and Cox proportional hazard regressions identified associations with resection and overall survival (OS). Survival was compared using Kaplan-Meier and log-rank tests.

RESULTS

Most patients (83%) in the cohort of 8560 patients had well-differentiated tumors (panNET). The median OS was 47 months (panNET, 63 months vs panNEC, 17 months; p < 0.001). Surgery was less likely for older patients (odds ratio [OR], 0.97), patients with panNEC (OR, 0.27), and patients with metastasis at diagnosis (OR, 0.08) (all p < 0.001). After propensity score-matching of these factors, surgical resection was associated with longer OS (82 vs 29 months; p < 0.001) and a decreased hazard of mortality (hazard ratio [HR], 0.37; p < 0.001). Surgery remained associated with longer OS when stratified by differentiation (98 vs 41 months for patients with panNET and 36 vs 8 months for patients with panNEC). Overall survival did not differ between patients with panNEC who underwent surgery and patients with panNET who did not (both 39 months; p = 0.294).

CONCLUSIONS

Poorly differentiated panNEC exhibits poorer survival than well-differentiated panNET. In the current cohort, surgical resection was strongly and independently associated with improved OS, suggesting that patients with panNEC who are suitable operative candidates should be considered for multimodality therapy, including surgery.

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

Objective

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

Background

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

Methods

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

Results

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

Conclusions

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

Predictive Factors for Resistant Disease with Medical/Radiologic/Liver-Directed Anti-Tumor Treatments in Patients with Advanced Pancreatic Neuroendocrine Neoplasms: Recent Advances and Controversies

Simple Summary

Tumor resistance, both primary and acquired, is leading to increased complexity in the nonsurgical treatment of patients with advanced panNENs, which would be greatly helped by reliable prognostic/predictive factors. The importance in identifying resistance is being contributed to by the increased array of possible treatments available for treating resistant advanced disease; the variable clinical course as well as response to any given treatment approach of patients within one staging or grading system, the advances in imaging which are providing increasing promising results/parameters that correlate with grading/outcome/resistance, the increased understanding of the molecular pathogenesis providing promising prognostic markers, all of which can contribute to selecting the best treatment to overcome resistance disease. Several factors have been identified that have prognostic/predictive value for identifying development resistant disease and affecting overall survival (OS)/PFS with various nonsurgical treatments of patients with advanced panNENs. Prognostic factors identified for patients with advanced panNENs for both OS/PFSs include various clinically-related factors (clinical, laboratory/biological markers, imaging, treatment-related factors), pathological factors (histological, classification, grading) and molecular factors. Particularly important prognostic factors for the different treatment modalities studies are the recent grading systems. Most prognostic factors for each treatment modality for OS/PFS are not specific for a given treatment option. These advances have generated several controversies and new unanswered questions, particularly those related to their possible role in predicting the possible sequence of different anti-tumor treatments in patients with different presentations. Each of these areas is reviewed in this paper.

Abstract

Purpose: Recent advances in the diagnosis, management and nonsurgical treatment of patients with advanced pancreatic neuroendocrine neoplasms (panNENs) have led to an emerging need for sensitive and useful prognostic factors for predicting responses/survival. Areas covered: The predictive value of a number of reported prognostic factors including clinically-related factors (clinical/laboratory/imaging/treatment-related factors), pathological factors (histological/classification/grading), and molecular factors, on therapeutic outcomes of anti-tumor medical therapies with molecular targeting agents (everolimus/sunitinib/somatostatin analogues), chemotherapy, radiological therapy with peptide receptor radionuclide therapy, or liver-directed therapies (embolization/chemoembolization/radio-embolization (SIRTs)) are reviewed. Recent findings in each of these areas, as well as remaining controversies and uncertainties, are discussed in detail, particularly from the viewpoint of treatment sequencing. Conclusions: The recent increase in the number of available therapeutic agents for the nonsurgical treatment of patients with advanced panNENs have raised the importance of prognostic factors predictive for therapeutic outcomes of each treatment option. The establishment of sensitive and useful prognostic markers will have a significant impact on optimal treatment selection, as well as in tailoring the therapeutic sequence, and for maximizing the survival benefit of each individual patient. In the paper, the progress in this area, as well as the controversies/uncertainties, are reviewed.

Resection of Primary Gastrointestinal Neuroendocrine Tumor Among Patients with Non-Resected Metastases Is Associated with Improved Survival: A SEER-Medicare Analysis

BACKGROUND

The objective of this study was to analyze whether primary tumor resection (PTR) among patients with stage IV gastrointestinal neuroendocrine tumor (GI-NET) and unresected metastases was associated with improved outcomes.

METHODS

Patients diagnosed with stage IV GI-NETs were identified in the linked SEER-Medicare database from 2004 to 2015. Overall survival (OS) of patients who did versus did not undergo PTR was examined using bivariate and multivariable cox regression analysis as well as propensity score matching (PSM).

RESULTS

Among 2219 patients with metastatic GI-NETs, 632 (28.5%) underwent PTR, whereas 1587 (71.5%) did not. The majority of individuals had a NET in the pancreas (n = 969, 43.6%); the most common site of metastatic disease was the liver (n = 1064, 47.9%). Patients with stage IV small intestinal NETs most frequently underwent PTR (62.6%) followed by individuals with colon NETs (56.5%). After adjusting for all competing factors, PTR remained independently associated with improved OS (HR = 0.65, 95% CI: 0.56-0.76). Following PSM (n = 236 per group), patients who underwent PTR had improved OS (median OS: 1.3 years vs 0.8 years, p = 0.016). While PTR of NETs originating from stomach, small intestine, colon, and pancreas was associated with improved OS, PTR of rectal NET did not yield a survival benefit.

CONCLUSION

Primary GI-NET resection was associated with a survival benefit among individuals presenting with metastatic GI-NET with unresected metastases. Resection of primary GI-NET among patients with stage IV disease and unresected metastases should only be performed in selected cases following multi-disciplinary evaluation.

Site-specific metastases of gallbladder adenocarcinoma and their prognostic value for survival: a SEER-based study

Background

Gallbladder cancer is a rare but highly malignant cancer, which often progresses to a metastatic stage when diagnosed because of its asymptomatic manifestation. In this study, we intended to analyze the prognostic value of metastatic gallbladder adenocarcinoma (GBA) with site-specific metastases.

Methods

Using the Surveillance, Epidemiology, and End Results (SEER) database, GBA patients diagnosed with metastases between 2010 and 2016 were selected to identify the prognosis according to the isolated metastatic sites, including liver, lung, bone, brain and distant lymph nodes (DL). Kaplan–Meier methods were used for survival comparisons and multivariable Cox regression models were constructed to find out independent factors that associated with survival.

Results

Data from 1526 eligible patients were extracted from the SEER database. Among the patients, 788 (51.6%) had isolated liver metastases, 80 (5.2%) had isolated distant nodal involvement, 45 (2.9%) had isolated lung metastases, 21 (1.4%) had isolated bone metastases, 2 (0.1%) had isolated brain metastases and 590 (38.7%) had multiple metastases. No significant survival difference was shown between patients with single or multisite metastases (P > 0.05). Patients with isolated lung or DL metastases had significant better survival outcomes than those with isolated bone metastases (P < 0.05). Multivariate analysis showed that performing surgery at primary site, receiving chemotherapy were associated with better OS and CSS for patients with isolated liver or DL metastases.

Conclusions

The study showed that different metastatic sites affect survival outcomes in metastatic GBA patients. Highly selected subset of patients with liver or DL metastases might benefit from surgery at primary site.

Understanding the Management and Treatment of Well-Differentiated Pancreatic Neuroendocrine Tumors: A Clinician's Guide to a Complex Illness

Pancreatic neuroendocrine tumors (PanNETs) are rare neoplasms that arise in the neuroendocrine cells of the pancreas. Although their clinical presentations differ depending on cell type, most are indolent, whereas others cause noteworthy hormone-related symptoms. The increasing incidence of PanNETs, attributed to improved diagnostic modalities, demonstrates advances in current standard of care. However, given the heterogeneity of these tumors, treatment decisions can become complex and an individualized approach is often required. Surgical intervention has remained the mainstay for localized tumors, whereas systemic therapies remain viable options for patients with unresectable or metastatic disease. Liver-directed therapies such as radiofrequency ablation and hepatic arterial embolization have also become available adjunct therapies for patients with liver-predominant metastases. Despite the increase in the armamentarium of treatment options for patients with PanNETs, data regarding the ideal sequence of treatment, especially systemic treatments, are currently lacking. Ongoing clinical trials are aimed at addressing this knowledge gap in addition to developing the next generation of novel therapeutics.

Resection of the Primary Gastrointestinal Neuroendocrine Tumor Improves Survival With or Without Liver Treatment

OBJECTIVE

The aim of this study was to determine outcomes of primary tumor resection in metastatic neuroendocrine tumors across all primary tumor sites.

BACKGROUND

Primary tumor resection (PTR) may offer a survival benefit in metastatic gastrointestinal neuroendocrine tumors (GI-NETs); however, few studies have examined the effect of primary site and grade on resection and survival.

METHODS

This is a retrospective study of patients with metastatic GI-NETs at presentation between 2005 and 2011 using the California Cancer Registry (CCR) dataset merged with California Office of Statewide Health Planning and Development (OSHPD) inpatient longitudinal database. Primary outcome was overall survival (OS). Univariate and multivariate (MV) analyses were performed using the Pearson Chi-squared tests and Cox proportional hazard, respectively. OS was estimated using the Kaplan-Meier method and log-rank test.

RESULTS

A total of 854 patients with GI-NET metastases on presentation underwent 392 PTRs. Liver metastases occurred in 430 patients; 240 received liver treatment(s). PTR improved OS in patients with untreated metastases (median survival 10 vs 38 months, P < 0.001). On MV analysis adjusted for demographics, tumor stage, grade, chemotherapy use, Charlson comorbidity index, primary tumor location, or treatment of liver metastases, PTR with/without liver treatment improved OS in comparison to no treatment [hazard ratio (HR) 0.50, P < 0.001 and 0.39, P < 0.001, respectively]. PTR offered a survival benefit across all grades (low-grade, HR 0.38, P = 0.002 and high-grade, HR 0.62, P = 0.025) CONCLUSION:: PTR in GI-NET is associated with a better survival, with or without liver treatment, irrespective of grade. This study supports the resection of the primary tumor in patients with metastatic GI-NETs, independent of liver treatment.

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.

Prognostic and predictive factors on overall survival and surgical outcomes in pancreatic neuroendocrine tumors: recent advances and controversies

Introduction: Recent advances in diagnostic modalities and therapeutic agents have raised the importance of prognostic factors in predicting overall survival, as well as predictive factors for surgical outcomes, in tailoring therapeutic strategies of patients with pancreatic neuroendocrine neoplasms (panNENs).Areas covered: Numerous recent studies of panNEN patients report the prognostic values of a number of clinically related factors (clinical, laboratory, imaging, treatment-related factors), pathological factors (histological, classification, grading) and molecular factors on long-term survival. In addition, an increasing number of studies showed the usefulness of various factors, specifically biomarkers and molecular makers, in predicting recurrence and mortality related to surgical treatment. Recent findings (from the last 3 years) in each of these areas, as well as recent controversies, are reviewed.Expert commentary: The clinical importance of prognostic and predictive factors for panNENs is markedly increased for both overall outcome and post resection, as a result of recent advances in all aspects of the diagnosis, management and treatment of panNENs. Despite the proven prognostic utility of routinely used tumor grading/classification and staging systems, further studies are required to establish these novel prognostic factors to support their routine clinical use.

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

BACKGROUND/AIMS

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Value of ileus-prophylactic surgery for metastatic neuroendocrine midgut tumours

Neuroendocrine tumours of the small intestine (SINET) are a rare disease. However, a rising incidence rate and excellent long-term survival, even in the setting of metastatic disease lead to a high prevalence of SINET of up to 11/100.000. At the time of diagnosis, most patients already suffer from metastatic disease. About one third of patients demonstrate localized or regional metastatic disease at time of presentation. For those patients the indication for curative surgery is not debated and 10-year cancer specific survival of almost 90% can be achieved. Due to major limitations of existing studies actually there is no sufficient evidence in favour of ileus-prophylactic palliative surgery for metastatic SINET. Until now the available evidence favouring an ileus-prophylactic palliative small bowel resection for stage IV SI-NET must be weighed against available high-level evidence from randomized trials that showed long-term survival under systemic therapy. Importantly, there is not a single study that indicates surgery for a symptomatic patient should be postponed. Because the majority of patients are symptomatic at the time of diagnosis, the rationale for an ileus-prophylactic palliative surgery is to operate before progression of mesenteric tumour mass and desmoplasia takes place and before intestinal obstruction and ischaemia occurs. To what extent a prophylactic palliative small bowel resection will provide a survival benefit in a situation where the mesenteric tumour mass cannot be resected radically is not clearly addressed by the current level of evidence.

Resection of the primary tumor improves survival in patients with gastro-entero-pancreatic neuroendocrine neoplasms with liver metastases: A SEER-based analysis

Patients who suffer from gastro‐entero‐pancreatic neuroendocrine neoplasms (GEP‐NENs) often present with liver metastatic disease. The efficacy of primary tumor resection (PTR) for these patients remains controversial due to the relatively heterogeneous behavior of the primary tumor and the lack of clinical evidence. In this series, GEP‐NEN patients with liver metastases (LM) were selected from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. A logistic regression model was used to analyze variables that were associated with PTR. A Cox proportional hazards model was used to identify independent prognostic risk factors. In total, 1547 patients were enrolled in our study, including 897 patients who underwent PTR. Resection of the primary tumor was associated with prolonged survival in all patients (5‐year overall survival (OS) rates: 57.0% vs 15.4%, P < .001), and improved 5‐year OS rates were observed in patients with gastric, small intestinal, colorectal, and pancreatic subtypes (39.7%, 73.3%, 24.6%, and 59.7%, respectively). On the multivariate analysis, PTR was an independent prognostic factor of prolonged OS (HR = 0.48, 95% CI: 0.39‐0.59, P < .001). Patients with a young age (≤60 years), small intestinal or colorectal NENs, a large primary tumor, lymph node (LN) metastases, and high tumor differentiation were more likely to undergo PTR. However, patients with colorectal NENs or a large primary tumor (≥4 cm) were at an increased risk of death independently in the PTR subgroup. The risk factors for OS also included old age, gastric tumor location, and poor differentiation. In conclusion, although PTR prolonged OS in all GEP‐NEN patients presenting with LM, surgical recipients should be considered carefully. Age, primary tumor site, size, and differentiation might help surgeons identify patients who could benefit from PTR.

A Surveillance, Epidemiology and End Results database analysis of the prognostic value of organ-specific metastases in patients with advanced prostatic adenocarcinoma

Prostate cancer (PCa) survival markedly decreases with the occurrence of distant metastasis, and treatment decisions can be influenced by metastasis site, and affect patient survival outcomes. The aim of the present study was to evaluate the potential prognostic value of metastasis to specific sites and the prognostic value of prostatectomy in patients with only bone metastasis, and to determine potential risk factors for bone metastasis in prostatic adenocarcinoma using large scale clinical data. The Surveillance, Epidemiology and End Results (SEER) database (2010–2013) was queried via the SEER*Stat (version 8.3.4) program. A total of 210,730 prostatic adenocarcinoma patients were identified from the SEER database between January 2010 and December 2013. Univariate and multivariate Cox regression analysis and Kaplan-Meier curves were used for survival comparisons with corresponding 95% confidence intervals. Patients with PCa with only liver metastatic lesions had worse overall and cancer-specific survival rates compared with those patients with only bone or lung metastasis. Multivariate Cox regression analysis revealed that age <50 years, married status, T1 and T3 tumor stage according to Tumor-Node-Metastasis (TNM) staging system from the 7th AJCC cancer staging manual, and prostatectomy were associated with better overall survival and cancer-specific survival in patients with only bone metastasis. Binary logistic regression analysis revealed that unmarried status, African descent and undifferentiated histological grade were risk factors for PCa bone metastasis. Prostatic adenocarcinoma patients with only liver metastasis had worse prognostic outcomes compared with patients with other distant organ metastases. Prostatectomy improved the 3-year survival rate in stage IV PCa patients and stage IV PCa patients with only bone metastasis. These findings were based on large-scale clinical data and can provide novel perspectives for the treatment of patients with advanced prostate adenocarcinoma.

Site-specific metastases of intrahepatic cholangiocarcinoma and its impact on survival: a population-based study

Aim: Limited data exist on impact of the metastatic sites on survival in patients with metastatic intrahepatic cholangiocarcinoma (ICC). Methods: Patients with metastatic ICC were identified in the SEER from 2010 to 2015. Results: A total of 981 patients were identified, of this population, liver (57.9%) is the most common site of ICC metastases, followed by lung, bone and brain. Respective median overall survival and cancer-specific survival were 6 and 9 months in entire population. Further analysis suggested that patients treated by surgery to primary and/or metastatic lesions had a better survival outcome than patients had no surgery (p ≤ 0.001). Conclusion: Liver is the most common site for ICC metastases, local treatment such as surgery to primary or metastatic lesions obviously benefit patients.

A Competing-Risks Nomogram in Patients with Metastatic Pancreatic Duct Adenocarcinoma

BACKGROUND The primary objective of this study was to assess the cumulative incidence of cause-specific mortality (CSM) and other causes of mortality (OCM) for patients with metastatic pancreatic duct adenocarcinoma (mPDAC). The secondary objective was to calculate the probability of CSM and build a competing risk nomogram to predict CSM for mPDAC. MATERIAL AND METHODS We identified patients with mPDAC between 2010 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database. We assessed the cumulative incidence function (CIF) for cause-specific mortality and other causes of mortality. We used Gray's test to investigate the differences. The Fine and Gray proportional subdistribution hazard model was applied to model CIF. And a competing risk nomogram was built to predict the probability of CSM for mPDAC. RESULTS There were 10 527 eligible patients diagnosed with mPDAC from 2010 to 2015 who were included in our formal analysis. The 6-month cumulative incidence of CSM was 60.3% and 5.9% for other causes. Predictors of SCM for mPDAC included surgery, age, tumor size, chemotherapy, radiation therapy, bone metastasis, and liver metastasis. The nomogram was proven to be well calibrated, and had good model discriminative ability. CONCLUSIONS We assessed the CIF of CSM and competing risk mortality in patients with mPDAC using the SEER database. The Fine and Gray proportional subdistribution hazard model performance was good, with a concordance index of 0.74, and the competing-risks nomogram was built, which can be a helpful predictive tool for cases with mPDAC. However, a validation sample data set and further verification are still needed to assess a profile for prognostic use in a prospective study.

Gastroenteropancreatic neuroendocrine tumors: Role of surgery

Natural history of gastroenteropancreatic (GEP) Neuroendocrine tumors (NETs) is better and better known so indications of surgery are presently selective. Surgical resection, but also endoscopic resection and observation, can be proposed for gastric NETs according to presentation, size and grade. For small bowel NETs, resection is frequently needed but should obtain the best compromise between radicality and postoperative functional disorders. Appendiceal NETs are frequently diagnosed by appendectomy for appendicitis, but some patients at high risk for lymph node metastasis and recurrence should be reoperated for radical resection. Rectal NETs are often diagnosed incidentally; the smallest (<1cm) can be resected endoscopically but the most aggressive need a oncological proctectomy. Pancreatic NETs represent a wide spectrum, ranging from fully benign tumors to very aggressive ones. Insulinomas are mostly benign, responsible for incapacitating symptoms despite medical treatment, and should ideally be treated by parenchyma sparing resection, mainly enucleation. Conversely, symptoms of gastrinomas are efficiently treated medically but their resection needs an oncological approach. Nonfunctioning PNETs are more and more frequently and incidentally discovered. According to their size, presentation and patient's characteristics, they need a resection (oncological or parenchyma-sparing) or a close observation.

Surgical resection of the primary tumor leads to prolonged survival in metastatic pancreatic neuroendocrine carcinoma

BACKGROUND

Palliative resection of the primary tumor for metastatic pancreatic neuroendocrine carcinoma (pNEC) patients is not recommended because of the poor prognosis compared to that of patients with well-differentiated, lower grade tumors. However, the published data supporting this recommendation regarding pNEC are limited. In the present study, we assessed whether palliative primary tumor resection in stage IV pNEC patients affects survival and identified other factors that affect survival in these patients.

METHODS

We collected data from stage IV pNEC patients registered in the Surveillance, Epidemiology, and End Results (SEER) database between 1988 and 2014. Univariate and multivariate Cox regression analysis were used to compare overall survival (OS) and cancer-specific survival (CSS) of patients who did or did not undergo primary tumor resection.

RESULTS

We identified 350 patients with metastatic, poorly differentiated, and undifferentiated pNEC. A total of 14.3% (50/350) of patients underwent primary tumor resection. Multivariate Cox regression analysis showed that primary tumor resection provided a significant benefit for both OS and CSS in stage IV pNEC patients. Additionally, chemotherapy and the presence of the primary tumor in the pancreatic tail were independent positive prognostic factors for metastatic pNEC patients in the multivariate Cox regression analysis.

CONCLUSIONS

The present study suggests that chemotherapy, location of the primary tumor in the pancreatic tail, and, most importantly, surgical removal of the primary tumor are associated with prolonged survival in stage IV pNEC patients.

Surgery for Pancreatic Neuroendocrine Tumor G3 and Carcinoma G3 Should be Considered Separately

BACKGROUND

The role of surgery in pancreatic neuroendocrine neoplasm grade 3 (pNEN-G3) treatment remains unclear. We aimed to clarify the role of surgery for pNEN-G3, which has recently been reclassified as pancreatic neuroendocrine tumor-G3 (pNET-G3) and pancreatic neuroendocrine carcinoma-G3 (pNEC-G3), with and without metastases, respectively.

METHODS

We analyzed a subgroup of patients from the Japanese pancreatic NEC study, a Japanese multicenter case-series study of pNEN-G3. Pathologists subclassified 67 patients as having pNET-G3 or pNEC-G3 based on morphological features. We compared the overall survival (OS) rates among patients who were grouped according to whether they had undergone tumor-targeted surgery for tumors without (SwoM) or with (SwM) metastases, or non-surgical procedures (NS).

RESULTS

Data from 21 patients with pNET-G3 (SwoM, n = 6; SwM, n = 5; NS, n = 10) and 46 patients with pNEC-G3 (SwoM, n = 8; SwM, n = 5; NS, n = 33) were analyzed. OS of patients with pNET-G3 was significantly longer after SwoM and SwM than with NS (p = 0.018 and p = 0.022). In contrast, OS did not significantly differ between either SwoM or SwM and NS (p = 0.093 and p = 0.489) among patients with pNEC-G3.

CONCLUSION

The role of surgery should be considered separately for pNET-G3 and pNEC-G3. Although SwoM and SwM can be considered for pNET-G3, caution is advised before considering SwM and SwoM for pNEC-G3.

Prevalence and prognostic impact of synchronous distant metastases in patients with hypopharynx squamous cell carcinomas: a SEER-based study

Background: The prognosis of hypopharynx squamous cell carcinoma (SCC) patients with distant metastasis is poor. We sought to explore prevalence and prognostic impact of synchronous distant metastases among patients with hypopharynx SCC in this study. Methods: Patients with histologically proven hypopharynx SCC were extracted from the Surveillance, Epidemiology and End Results (SEER) database between 2010 and 2014. We examined the relationship between tumor factors and distant metastases using Chi-squared tests and we evaluated the association between survival and different variables using the methods of Kaplan-Meier. Univariate analysis was performed using the log-rank test. Multivariate analyses with the Cox proportional hazards model were used to test the independent significance of the predictors, and two-tailed p-values less than 0.05 were considered statistically significant. Results: We finally identified 1780 patients who were diagnosed with hypopharynx SCC and the most frequent site of distant metastases was lung. Some clinical characteristics, including age, gender, race, histological grade, T classification and N classification were independent risk factors. Higher T or N category, posterior wall of hypopharynx cancers and multiple sites of metastases were associated with poorer overall survival. For cancer-specific survival, elderly patients with higher T category, advanced N category, posterior wall of hypopharynx cancers, multiple sites of metastases and no surgery therapies to the primary tumor were associated with worse survival. Conclusion: This is the first SEER analysis assessing prevalence and prognostic impact of synchronous distant metastases in a large cohort of patients with hypopharynx SCC. Poorer prognosis was associated with elderly patients, higher T category, advanced N category, posterior wall of hypopharynx cancers, no surgery therapies to the primary tumor and more metastatic sites.

Rare malignant insulinoma with multiple liver metastases derived from ectopic pancreas: 3-year follow-up and literature review

Here, we report the diagnosis and treatment of a very rare case of malignant insulinoma derived from ectopic pancreas. A middle-aged woman presented with a 6-year history of recurrent hypoglycemia with multiple lesions in liver. Admission workup revealed elevated serum insulin and C-peptide, as well as multiple lesions in the liver (largest being 4.3 cm), enlarged lymph nodes around the pancreas, and a lesion (of 3.5 cm) at the proximal jejunum, as shown by contrast computed tomography (CT). Liver biopsy showed the lesions to be well-differentiated neuroendocrine tumors, grade G1. 68Gallium-exendin-4 positron emission tomography/CT confirmed the origin as the lesion located at the jejunum. The combination treatment of everolimus plus long-acting octreotide relieved symptoms and achieved a partial tumor response. Maintenance treatment of the somatostatin analog (ie, octreotide) alone was administered. Three years of follow-up, up to the writing of this report, showed good survival, with the patient remaining asymptomatic and euglycemic without disease progression. This case shows that 68Gallium-exendin-4 positron emission tomography/CT is useful for locating insulinoma, especially for insulinoma derived from ectopic pancreas, and that everolimus plus octreotide with maintenance somatostatin analog alone is an effective drug strategy for treating inoperable malignant insulinoma.

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.

Clinical correlates and prognostic value of different metastatic sites in metastatic renal cell carcinoma

Aim: Real life data on the clinical correlates and prognostic value of metastatic sites in metastatic renal cell carcinoma (RCC) are needed. This parameter was assessed in RCC patients registered within the surveillance, epidemiology and end results (SEER) database. Methods: Data were obtained from the National Cancer Institute-SEER database spanning 2010-2013; and it has been accessed through SEER*Stat program to determine the clinical correlates and prognosis of RCC patients with distant metastases according to the site of metastasis. Multivariate analyses were performed using Cox regression analysis to determine factors associated with improved overall and cancer-specific survival. Kaplan-Meier curves and log-rank tests were used to calculate and compare survival estimates. Results: A total of 5992 patients with metastatic RCC were identified in the period from 2010 to 2013. Patients with isolated liver metastases have worse survival outcomes compared with patients with other single organ sites of metastases. Pairwise p-values for cancer-specific survival: bone metastasis versus liver metastasis: p < 0.0001; lung metastasis versus liver metastasis: p = 0.002; distant lymph nodes versus liver metastasis: p = 0.006. Multivariate analysis revealed that younger age at diagnosis (p < 0.0001), single organ site of metastatic disease (p = 0.046), male gender (p = 0.001), earlier T stage (p < 0.0001), node negative status (p < 0.0001), clear cell histology (p = 0.001), local treatment to the primary tumor (p < 0.0001) and surgery to the metastatic disease (p < 0.0001) were associated with better overall survival. The same factors (except age) were associated with better cancer-specific survival. Conclusion: Metastatic RCC patients with liver metastases seem to have worse outcomes compared with patients with other sites of metastases.

Prognostic value of site-specific extra-hepatic disease in hepatocellular carcinoma: a SEER database analysis

BACKGROUND

We the prognostic value of site-specific extra-hepatic disease in hepatocellular carcinoma (HCC) patients registered within the surveillance, epidemiology and end results (SEER) database.

METHODS

SEER database (2010-2013) has been queried through SEER*Stat program to determine the prognosis of advanced HCC patients according to the site of extra-hepatic disease. Survival analysis has been conducted through Kaplan Meier analysis.

RESULTS

A total of 4396 patients with stage IV HCC were identified in the period from 2010-2013 and they were included into this analysis. Patients with isolated regional lymph node involvement have better outcomes compared to patients with any other site of extra-hepatic disease (P < 0.0001 for both endpoints). Among patients with distant metastases, patients with bone metastases have better outcomes compared to patients with lung metastases (P < 0.0001 for both endpoints). Multivariate analysis revealed that younger age, normal alpha fetoprotein, single site of extra-hepatic disease, local treatment to the primary tumor and surgery to the metastatic disease were associated with better overall survival and liver cancer-specific survival.

CONCLUSION

Within the limits of the current SEER analysis, HCC patients with isolated lung metastases seem to have worse outcomes compared to patients with isolated bone or regional nodal metastases.​.

Pancreatic neuroendocrine tumors: the basics, the gray zone, and the target

Pancreatic neuroendocrine tumors (PanNETs) manifest with a range of symptoms and pose a therapeutic challenge. A team approach, in which many specialists come together, is necessary in the quest for the best patient-tailored treatment. Disciplines such as oncology, surgery, basic science, endocrinology, radiology, and nuclear medicine need to work side by side, equally contributing to patient care and to advancing our better understanding of this fascinating disease.

Pancreatic Neuroendocrine Tumors (panNETs): Analysis of Overall Survival of Nonsurgical Management Versus Surgical Resection

BACKGROUND

Outcomes of patients with pancreatic neuroendocrine tumors (panNETs) undergoing surgical or nonsurgical management and outcomes of enucleation versus standard resection were compared.

METHODS

MEDLINE, EMBASE, PubMed, Scopus, and Cochrane were queried (2000 to present). All studies comparing patients undergoing surgical versus nonsurgical treatments, or enucleation versus standard resection, were included. Pooled risk ratios and 95% CI for survival were calculated.

RESULTS

Eleven studies met criteria with 1491 resected and 1607 nonsurgically managed patients. Meta-analysis showed improved overall survival with resection at 1 year (risk ratio (RR) = 1.281, CI 1.064-1.542, p = 0.009), 3 years (RR = 1.837, CI 1.594-2.117, p < 0.001), and 5 years (RR = 2.103, CI 1.50-2.945, p < 0.001). OS of patients with resected nonfunctioning panNETs was improved at 3 years (RR = 1.847, CI 1.477-2.309, p < 0.001) and 5 years (RR = 1.767, CI 1.068-2.924, p = 0.027). OS was improved when panNETs ≤2 cm were resected at 3 years (RR = 1.695, CI 1.269-2.264, p < 0.001) and 5 years (RR = 2.210, CI 1.749-2.791, p < 0.001). Fifteen articles met criteria for enucleation versus standard resection (n = 1035; 620 were nonfunctioning). Enucleation had shorter operative time (weighted mean difference (WMD) = -95.6 min, 95% CI -131.4 to -59.8, p < 0.01), less operative blood loss (WMD = -172.6 ml, 95% CI -340 to -5.1, p = 0.04), but increased postoperative pancreatic fistula (POPF) (RR = 2.08, 95% CI 1.39-3.12, p < 0.01).

CONCLUSION

Surgical resection of panNETs, including small and nonfunctioning, appears to be associated with improved OS. Enucleation is associated with shorter operative time, less blood loss, but greater incidence of POPF. Prospective, randomized clinical trials are needed to confirm these results.

Prognostic value of site-specific metastases in pancreatic adenocarcinoma: A Surveillance Epidemiology and End Results database analysis

AIM

To evaluate the prognostic value of site-specific metastases among patients with metastatic pancreatic carcinoma registered within the Surveillance, Epidemiology and End Results (SEER) database.

METHODS

SEER database (2010-2013) has been queried through SEER*Stat program to determine the presentation, treatment outcomes and prognostic outcomes of metastatic pancreatic adenocarcinoma according to the site of metastasis. In this study, metastatic pancreatic adenocarcinoma patients were classified according to the site of metastases (liver, lung, bone, brain and distant lymph nodes). We utilized chi-square test to compare the clinicopathological characteristics among different sites of metastases. We used Kaplan-Meier analysis and log-rank testing for survival comparisons. We employed Cox proportional model to perform multivariate analyses of the patient population; and accordingly hazard ratios with corresponding 95%CI were generated. Statistical significance was considered if a two-tailed P value < 0.05 was achieved.

RESULTS

A total of 13233 patients with stage IV pancreatic cancer and known sites of distant metastases were identified in the period from 2010-2013 and they were included into the current analysis. Patients with isolated distant nodal involvement or lung metastases have better overall and pancreatic cancer-specific survival compared to patients with isolated liver metastases (for overall survival: lung vs liver metastases: P < 0.0001; distant nodal vs liver metastases: P < 0.0001) (for pancreatic cancer-specific survival: lung vs liver metastases: P < 0.0001; distant nodal vs liver metastases: P < 0.0001). Multivariate analysis revealed that age < 65 years, white race, being married, female gender; surgery to the primary tumor and surgery to the metastatic disease were associated with better overall survival and pancreatic cancer-specific survival.

CONCLUSION

Pancreatic adenocarcinoma patients with isolated liver metastases have worse outcomes compared to patients with isolated lung or distant nodal metastases. Further research is needed to identify the highly selected subset of patients who may benefit from local treatment of the primary tumor and/or metastatic disease.

Pathology and Surgical Treatment of High-Grade Pancreatic Neuroendocrine Carcinoma: an Evolving Landscape

Pancreatic neuroendocrine neoplasms (PNENs) are rare, accounting for less than 5% of all pancreatic tumors. High-grade pancreatic neuroendocrine carcinomas (hgPNECs) represent about 5% of all PNENs. They show highly aggressive behavior with dismal prognosis. Throughout the last two decades, there has been a notable progress in basic and clinical research of PNENs and a therapeutic trend towards both more aggressive and minimally invasive surgery. Despite these advances, hgPNECs as a distinct clinical entity remains largely unexplored among surgeons. This review of current development in pathology reporting and surgical treatment of hgPNECs aims at increasing the awareness of an evolving field in pancreatic surgery.

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.