Management of asymptomatic, well-differentiated PNETs: results of the Delphi consensus process of the Americas Hepato-Pancreato-Biliary Association

Contemporary Approaches to the Surgical Management of Pancreatic Neuroendocrine Tumors

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

Premalignant Lesions in the Kidney Transplant Candidate

End-stage kidney disease patients who are referred for transplant undergo an extensive evaluation process to ensure their health prior to transplant due in part to the shortage of available organs. Although management and surveillance guidelines exist for malignancies identified in the transplant and waitlist populations, less is written about the management of premalignant lesions in this population. This review covers the less common premalignant lesions (intraductal papillary mucinous neoplasm, gastrointestinal stromal tumor, thymoma, and pancreatic neuroendocrine tumor) that can be found in the transplant candidate population. High-level evidence for the management of these rarer premalignant lesions in the transplant population is lacking, and this review extrapolates evidence from the general population and should not be a substitute for a multidisciplinary discussion with medical and surgical oncologists.

The Evolving Landscape of Neuroendocrine Tumors

Neuroendocrine tumors (NETs) represent a heterogeneous group of tumors, with variable presentation based on the location of origin and degree of metastatic spread. There are no randomized control trials to guide surgical management; however, surgery remains the mainstay of treatment for most gastroenteropancreatic NETs based on retrospective studies. Metastatic disease is common at the time of presentation, particularly in the liver. There is a role for cytoreduction for improvement of both symptoms and survival. Robust prospective randomized data exists to support the use of medical therapies to improve progression-free and overall survival in patients with advanced, metastatic, and unresectable NETs.

Immunotherapy improved cancer related pain management in patients with advanced Hepato-Pancreatic Biliary Cancers: A propensity score-matched (PSM) analysis

Background

Hepato-pancreato-biliary (HPB) cancer is a serious form of cancer. in many HPB cancers, including cholangiocarcinoma (also known as bile duct cancer), pancreatic cancer, hepatocellular carcinoma, gallbladder cancer and ampullary cancer, although several treatment options are developed during these decades, the prognosis is still poor.

Methods

A total of 356 HPB cancers patients in advanced stage received different kinds of treatments including adjuvant chemotherapy, radiotherapy, targeted therapy and immunotherapy. Among these patients with advanced HPB cancers, 135 patients have received standard opioid treatment for pain controlling.

Results

We performed a PSM analysis to minimize differences between groups. Before PSM, 135 patients received standard opioid treatment for pain controlling were enrolled in this study and divided into 4 groups, including chemotherapy, radiotherapy, targeted therapy and immunotherapy. Relevant clinical variables that were available at the time of initial diagnosis were used for 1:1 matching between the two groups. After PSM, the cohort consisted of 18 patients in each group. Prior to PSM, patients received targeted therapy and immunotherapy exhibited shorter median OSs than their counterparts for patients received chemotherapy and radiotherapy (p<0.001). there were so survival differences among all the four different treatments for these patients with HPB cancers (p>0.05). We found the OMED (mg) q/day and NRS scores decreased significantly when patients received immunotherapy treatment. Fewer adverse events were showed between immunotherapy group and other three treatment groups, which was consistent with our previous reports.

Conclusion

In conclusion, we found that given the same survival benefit, immunotherapy reduced opioid consumption in HPB cancers patients and improved the pain management. Moreover, immunotherapy results in fewer other adverse effects.

Assessing the Role of Operative Intervention in Elderly Patients With Nonfunctional Pancreatic Neuroendocrine Neoplasms

OBJECTIVES

Resection of locoregional pancreatic neuroendocrine neoplasms (PanNENs) is typically recommended, but there is a paucity of data on the management of elderly patients.

METHODS

The National Cancer Database (2004-2016) was queried for patients 80 years or older with localized PanNENs. Patients were grouped as nonoperative or operative management. Postoperative outcomes and survival were compared.

RESULTS

In total, 591 patients were included: 202 underwent resection, and 389 did not. Increasing age and pancreatic head tumors were associated with lower likelihood of resection. The overall 90-day mortality rate was 6.4%, which was higher for pancreatoduodenectomy than distal pancreatectomy (13.6% vs 5.1%, respectively). Operatively managed patients had longer median survival (80.8 vs 45.0 months, P < 0.001), and this association was independent of tumor location. On multivariable Cox regression, resection remained associated with longer survival (hazard ratio, 0.69; 95% confidence interval, 0.50-0.95). Among operatively managed patients, age and tumor location were not associated with survival; however, greater comorbidity and high-risk tumor-specific features were associated with worse survival.

CONCLUSIONS

Resection of nonfunctional PanNENs in elderly patients is associated with improved survival compared with nonoperative management. Resection could be considered in appropriate operative candidates, regardless of tumor location, but the perioperative mortality rate must be considered.

Facility type and size-stratified analysis of management patterns and outcomes of patients with localized non-functional pancreatic neuroendocrine tumors

BACKGROUND

Non-functional neuroendocrine tumors of the pancreas (NF-pNETs) are uncommon. Consensus guidelines have conflicting recommendations. We performed a nationwide analysis of patterns in management and outcomes based on facility type and tumor size.

METHODS

The National Cancer Database (2004-2016) was queried for patients with localized NF-pNETs (<1 cm, 1-2 cm, >2 cm) stratified by facility type. Management decisions, operative outcomes, and survival were compared.

RESULTS

A total of 7170 patients were included in the analysis (<1 cm = 916; 1-2 cm = 2180; >2 cm = 4074). Most patients were treated at academic facilities (62.8%). Over 67% of patients with tumors <1 cm underwent resection, independent of facility type (p = 0.443). There was no association between facility type and operative vs non-operative management of patients with NF-pNETs 1-2 cm in size. Patients treated at academic facilities were more likely to undergo resection for tumors >2 cm compared to other facility types. Resection was associated with improved survival among patients with tumors 1-2 cm (HR = 0.43,p < 0.001) and >2 cm (HR = 0.32,p < 0.001), but not <1 cm (HR = 0.64,p = 0.054), as compared to non-operative management.

CONCLUSION

There is heterogeneity in management of NF-pNETs across facility types. Treatment at academic facilities appears to be associated with higher resection rates for tumors >2 cm. There appears to be an independent association between operative management and improved survival for tumors ≥1 cm in size.

Fate of Surgical Patients with Small Nonfunctioning Pancreatic Neuroendocrine Tumors: An International Study Using Multi-Institutional Registries

Simple Summary

No consensus has been reached regarding whether nonmetastatic nonfunctioning neuroendocrine tumors of the pancreas (NF-pNETs) ≤ 2 cm should be resected or observed. In this retrospective international multicenter study, 483 patients who underwent resection for NF-pNETs ≤ 2 cm in 18 institutions from 2000 to 2017 were enrolled and their medical records were reviewed. Tumor size > 1.5 cm, Ki-67 index ≥ 3%, and nodal metastasis were independent adverse prognostic factors for survival after multivariable analysis. NF-pNET patients with tumors ≤ 1.5 cm can be observed if the preoperative Ki-67 index is under 3%, and if nodal metastasis is not suspected in preoperative radiologic studies. These findings support the clinical use to make decisions about small NF-pNETs.

Abstract

Several treatment guidelines for sporadic, nonmetastatic nonfunctioning neuroendocrine tumors of the pancreas (NF-pNETs) have recommended resection, however, tumors ≤ 2 cm do not necessarily need surgery. This study aims to establish a surgical treatment plan for NF-pNETs ≤ 2 cm. From 2000 to 2017, 483 patients who underwent resection for NF-pNETs ≤ 2 cm in 18 institutions from Korea and China were enrolled and their medical records were reviewed. The median age was 56 (range 16–80) years. The 10-year overall survival rate (10Y-OS) and recurrence-free survival rate (10Y-RFS) were 89.8 and 93.1%, respectively. In multivariable analysis, tumor size (>1.5 cm; HR 4.28, 95% CI 1.80–10.18, p = 0.001) and nodal metastasis (HR 3.32, 95% CI 1.29–8.50, p = 0.013) were independent adverse prognostic factors for OS. Perineural invasion (HR 4.36, 95% CI 1.48–12.87, p = 0.008) and high Ki-67 index (≥3%; HR 9.06, 95% CI 3.01–27.30, p < 0.001) were independent prognostic factors for poor RFS. NF-pNETs ≤ 2 cm showed unfavorable prognosis after resection when the tumor was larger than 1.5 cm, Ki-67 index ≥ 3%, or nodal metastasis was present. NF-pNET patients with tumors ≤ 1.5 cm can be observed if the preoperative Ki-67 index is under 3%, and if nodal metastasis is not suspected in preoperative radiologic studies. These findings support the clinical use to make decisions about small NF-pNETs.

Racial disparities in operative management of localized, non-functional pancreatic neuroendocrine tumors in surgically fit patients

BACKGROUND

Guidelines recommend resection of non-functional neuroendocrine tumors of the pancreas (NF-pNETs) that are ≥2 cm in size. We compared utilization of surgery based on race.

METHODS

We identified non-Hispanic White and Black patients with localized NF-pNETs ≥2 cm and Charlson-Deyo score 0-1 in the NCDB (2004-2016). We compared utilization of surgery by race, adjusting for clinicodemographic variables. Overall survival was compared based on management.

RESULTS

A total of 3459 patients were included (White = 3005; Black = 454). Black patients were younger (58vs63 years) and more often treated at academic facilities (65.3%vs60.3%). Overall, Black and White patients underwent surgery at similar rates (77.3%vs79.6%). When stratified by primary site, Black patients with body/tail tumors were less likely to undergo surgery (78.5%vs84.7%). On multivariable analysis, Black race was associated with a lower likelihood of surgery overall (OR 0.74,p = 0.034) and in patients with body/tail tumors (OR 0.56,p = 0.001). Non-operative management was associated with a higher risk of death (HR 3.19,p < 0.001).

CONCLUSION

In a national cohort of patients with NF-pNETs meeting criteria for resection, Black race is associated with lower frequency of surgery. Operative intervention is associated with prolonged survival. Persistent racial disparities in management of a surgically curable disease should be targeted for improvement.

Management of early hepatocellular carcinoma: results of the Delphi consensus process of the Americas Hepato-Pancreato-Biliary Association

BACKGROUND

There are many potential treatment options for patients with early stage hepatocellular carcinoma (HCC) and practice patterns vary widely. This project aimed to use a Delphi conference to generate consensus regarding the management of small resectable HCC.

METHODS

A base case was established with review by members of AHPBA Research Committee. The Delphi panel of experts reviewed the literature and scored clinical case statements to identify areas of agreement and disagreement. Following initial scoring, discussion was undertaken, questions were amended, and scoring was repeated. This cycle was repeated until no further likelihood of reaching consensus existed.

RESULTS

The panel achieved agreement or disagreement consensus regarding 27 statements. The overarching themes included that resection, ablation, transplantation, or any locoregional therapy as a bridge to transplant were all appropriate modalities for early or recurrent HCC. For larger lesions, consensus was reached that radiofrequency ablation and microwave ablation were not appropriate treatments.

CONCLUSION

Using a validated system for identifying consensus, an expert panel agreed that multiple treatment modalities are appropriate for early stage HCC. These consensus guidelines are intended to help guide physicians through treatment modalities for early HCC; however, clinical decisions should continue to be made on a patient-specific basis.

Watchful waiting for small non-functional pancreatic neuroendocrine tumours: nationwide prospective cohort study (PANDORA)

This prospective nationwide cohort study examined the feasibility of a watchful-waiting protocol for non-functional pancreatic neuroendocrine tumours (NF-pNET) of 2 cm or smaller. In total, 8 of 76 patients (11 per cent) with a NF-pNET no larger than 2 cm showed significant tumour progression (more than 0.5 cm/year) during 17 months of follow-up, of whom two opted for resection. No patient developed metastases. Quality of life was poorer than in the reference population. Watchful waiting seems a safe alternative to upfront surgery in patients with a NF-pNET no larger than 2 cm, although longer follow-up is necessary.

The Role of Laparoscopic Surgery in Localized Pancreatic Neuroendocrine Tumours

Pancreatic neuroendocrine tumours (PNETs) are a rare and heterogeneous group of tumours with various clinical manifestations and biological behaviours. They represent approximately 2-4% of all pancreatic tumours, with an incidence of 2-3 cases per million people. PNETs are classified clinically as non-functional or functional, and pancreatic resection is recommended for lesions greater than 2 cm. The surgical approach can involve "typical" and "atypical" resections depending on the number, size and location of the tumour. Typical resections include pancreaticoduodenectomy, distal pancreatectomy enucleation and, rarely, total pancreatectomy. Atypical resections comprise central pancreatectomies or enucleations. Minimally invasive pancreatic resection has been proven to be technically feasible and safe in high-volume and specialized centres with highly skilled laparoscopic surgeons, with consolidated benefits for patients in the postoperative course. However, open and minimally invasive pancreatic surgery remains to have a high rate of complications; there is no specific technical contraindication to minimally invasive pancreatic surgery, but an appropriate patient selection is crucial to obtain satisfactory clinical and oncological outcomes.

A Survival Analysis of Patients with Localized, Asymptomatic Pancreatic Neuroendocrine Tumors: No Surgical Survival Benefit when Examining Appropriately Selected Outcomes

BACKGROUND

Surgical resection for asymptomatic, localized, well-differentiated pancreatic neuroendocrine tumors (PNETs) is common yet controversial. Studies using overall survival as an endpoint have shown a benefit for resection; however, these results may be due to treatment selection bias. We assessed the impact of surgery on both overall (OS) and cancer-specific survival (CSS) for asymptomatic patients with stage I PNETs (AJCC 8th edition).

METHODS

Using SEER data, we identified 709 patients from 2007 to 2015 with well- and moderately differentiated stage I PNETs. We performed Kaplan-Meier survival estimates and adjusted Cox regression for OS and CSS.

RESULTS

Among 709 patients, 628 (88.6%) underwent surgery. There were 37 overall deaths and 11 cancer-specific deaths. All cancer-specific deaths occurred within 3 years of diagnosis. Five-year OS and CSS rates were 89% and 98%, respectively, for the population. Five-year OS rates were 56% in the non-surgical cohort versus 92% in the surgical cohort (log rank, p < 0.001). However, the 5-year CSS rates were similar; 94% in the non-surgical group and 98% in the surgical group (log rank, p  = 0.207). On multivariable analysis, surgery predicted improved OS but not CSS.

CONCLUSION

Although OS is superior in surgically treated stage I PNETs, CSS is not improved, implying treatment selection bias towards surgery being performed in healthier patients. These data suggest that overall survival is a problematic endpoint for the study of asymptomatic, stage I PNETs. Surgery should be individualized for this cohort of patients as the primary cause of death is non-cancer related.

The Landmark Series: Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) comprise a heterogeneous group of neoplasms arising from pancreatic islet cells that remain relatively rare but are increasing in incidence worldwide. While significant advances have been made in recent years with regard to systemic therapies for patients with advanced disease, surgical resection remains the standard of care for most patients with localized tumors. Although formal pancreatectomy with regional lymphadenectomy is the standard approach for most PNETs, pancreas-preserving approaches without formal lymphadenectomy are acceptable for smaller tumors at low risk for lymph node metastases. Furthermore, observation of small, asymptomatic, low-grade PNETs is a safe, initial strategy and is generally recommended for tumors < 1 cm in size. In this Landmark Series review, we highlight the critical studies that have defined the surgical management of PNETs.

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.