Local treatment for focal progression in metastatic neuroendocrine tumors

Therapy Sequencing in Patients With Advanced Neuroendocrine Neoplasms

Neuroendocrine neoplasms (NENs) comprise a beautifully complicated, exciting landscape of histologies and clinical behaviors. However, the nuanced complexity of low- and high-grade variants can easily overwhelm both patients and providers. In this chapter, we review the ever-expanding literature on both functioning and nonfunctioning small bowel and pancreatic NENs, touching on somatostatin analogs, hepatic-directed therapies, small molecules, radiopharmaceuticals, immunotherapy, cytotoxic chemotherapy, and new promising agents. Furthermore, we suggest some strategies to address the most challenging scenarios seen in clinical practice, including sequencing of agents, treatment of carcinoid syndrome, and options for well-differentiated high-grade disease.

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.

Case Report: Grade 2 Metastatic Pancreatic Neuroendocrine Tumor With Progression of One Metastasis After Pregnancy to Grade 3 Large-Cell Neuroendocrine Carcinoma: One Case Cured by Resection With Genomic Characterization of the Two Components

Temporal and spatial tumor heterogeneity can be observed in pancreatic neuroendocrine tumor. We report the case of a young woman with long term stabilization of a G2 metastatic pancreatic NET that, after pregnancy, suddenly progressed into one single liver metastasis corresponding to a transformation into G3 large-cell neuroendocrine cancer. The patient underwent liver resection (the progressive and one dormant metastasis). With a 45 months follow-up the patient is without evolutive disease. Exome sequencing of the two metastases revealed completely different genomic signatures and gene alterations: the dormant metastasis was MSS without any gene alteration; the poorly differentiated tumor was MSI, with gain of many mutations including MEN1, BCL2, MLH1 and TP53 corresponding to a mutational signature 11. Could temozolomide play a role in this transformation?

Liver Embolisation for Patients with Neuroendocrine Neoplasms: Systematic Review

BACKGROUND

Liver embolisation is one of the treatment options available for patients diagnosed with neuro-endocrine neoplasms (NEN). It is still uncertain whether the benefits of the various types of embolisation treatments truly outweigh the complications in NENs. This systematic review assesses the available data relating to liver embolisation in patients with NENs.

METHODS

Eligible studies (identified using MEDLINE-PubMed) were those reporting data on NEN patients who had undergone any type of liver embolisation. The primary end points were best radiological response and symptomatic response; secondary end-points included progression-free survival (PFS), overall survival (OS) and toxicity.

RESULTS

Of 598 studies screened, 101 were eligible: 16 were prospective (15.8%). The eligible studies included a total of 5,545 NEN patients, with a median of 39 patients per study (range 5-214). Pooled rate of partial response was 36.6% (38.9% achieved stable disease) and 55.2% of patients had a symptomatic response to therapy when pooled data were analysed. The median PFS and OS were 18.4 months (95% CI 15.5-21.2) and 40.7 months (95% CI 35.2-46.2) respectively. The most common toxicities were found to be abdominal pain (48.8%) and nausea (48.1%). Outcome did not significantly vary depending on the type of embolisation performed.

CONCLUSION

Liver embolisation provides adequate symptom relief for patients with carcinoid syndrome and is also able to reach partial response in a significant proportion of patients and a reasonable PFS. Quality of studies was limited, highlighting the need of further prospective studies to confirm the most suitable form of liver embolisation in NENs.

Pattern of disease recurrence and treatment after surgery for nonfunctioning well-differentiated pancreatic neuroendocrine tumors

BACKGROUND

The risk of recurrence after curative surgery for pancreatic neuroendocrine tumors is reported to be between 10% and 30%. Among the available locoregional and systemic treatments, there are no specific recommendations regarding the best option for treating recurrent disease. The aims of this study were to evaluate the pattern of recurrence after surgery performed with curative intent for nonfunctioning pancreatic neuroendocrine tumors and to analyze the impact of treatment on disease progression.

METHODS

All patients submitted to curative surgery for sporadic, well-differentiated, nonfunctioning pancreatic neuroendocrine tumors at 2 Italian centers between 2001 and 2018, with evidence of disease recurrence during follow-up, were included (n = 46).

RESULTS

The most frequent type of recurrence was distant metastases (n = 38, 83%), located in the liver in 100% of cases, whereas 8 patients (17%) had an isolated local recurrence. Therapy for first disease recurrence included both locoregional (n = 14) and systemic treatments (n = 32). A second disease recurrence/progression occurred in 28 patients (61%). Patients who underwent systemic treatment after the first disease recurrence had better progression-free survival (1-year progression-free survival 78%) compared with those submitted to a locoregional procedure (1-year progression-free survival 50%; P = .007). Independent predictors of shortened progression-free survival after the first disease recurrence were the type of treatment (locoregional, hazard ratio 4.452, P = .001), the presence of necrosis (hazard ratio 2.732, P = .022) and age (>60 year, hazard ratio 2.494, P = .040).

CONCLUSION

Upfront locoregional treatment of the first recurrence of nonfunctioning pancreatic neuroendocrine tumors after curative surgery should be avoided in favor of systemic therapy.

Surgical Principles in the Management of Pancreatic Neuroendocrine Neoplasms

OPINION STATEMENT

Pancreatic neuroendocrine neoplasms (PanNENs) are increasingly recognized entities, whose incidence has dramatically grown during the last two decades. Surgery plays a pivotal role in their management as it represents the only chance of cure. Since PanNENs display a wide range of aggressiveness, their surgical management needs to be tailored on tumor's and patient's characteristics. Currently, there are several open questions and burning issues in the field of PanNEN, such as the management of asymptomatic nonfunctioning pancreatic neuroendocrine tumors (NF-PanNET) ≤ 2 cm. An active surveillance of these small lesions has been demonstrated to be safe although the available evidences are only based on retrospective studies. On the other hand, formal pancreatic resection associated with lymphadenectomy represents the gold standard for patients with localized NF-PanNEN > 2 cm or NF-PanNEN ≤ 2 cm in the presence of symptoms, dilation of the main pancreatic duct or suspicion of nodal metastases. Surgery plays also an important role in the setting of metastatic disease. In particular, surgery is generally recommended in the presence of low-grade, resectable, metastatic disease, but several series have reported also a survival benefit of palliative primary tumor resection in patients with unresectable liver metastases. The role of surgery in PanNEN G3 is still controversial. Indeed, surgery is associated with an improved survival in patients with well-differentiated PanNET G3, whereas there is almost no survival benefit in case of poorly differentiated lesions.