Pancreatic neuroendocrine tumors: Therapeutic challenges and research limitations

Abstract

Pancreatic neuroendocrine tumors (PNETs) are known to be the second most common epithelial malignancy of the pancreas. PNETs can be listed among the slowest growing as well as the fastest growing human cancers. The prevalence of PNETs is deceptively low; however, its incidence has significantly increased over the past decades. According to the American Cancer Society’s estimate, about 4032 (> 7% of all pancreatic malignancies) individuals will be diagnosed with PNETs in 2020. PNETs often cause severe morbidity due to excessive secretion of hormones (such as serotonin) and/or overall tumor mass. Patients can live for many years (except for those patients with poorly differentiated G3 neuroendocrine tumors); thus, the prevalence of the tumors that is the number of patients actually dealing with the disease at any given time is fairly high because the survival is much longer than pancreatic ductal adenocarcinoma. Due to significant heterogeneity, the management of PNETs is very complex and remains an unmet clinical challenge. In terms of research studies, modest improvements have been made over the past decades in the identification of potential oncogenic drivers in order to enhance the quality of life and increase survival for this growing population of patients. Unfortunately, the majority of systematic therapies approved for the management of advanced stage PNETs lack objective response or at most result in modest benefits in survival. In this review, we aim to discuss the broad challenges associated with the management and the study of PNETs.

Integrating Gemcitabine-Based Therapy With AdipoRon Enhances Growth Inhibition in Human PDAC Cell Lines

“…Arising from either ductal or acinar cells of the exocrine portion, pancreatic ductal adenocarcinoma (PDAC) accounts for 90% of all pancreatic cancers, while the remainder chiefly evolves from Langerhans islets ( Gao et al, 2020 ). While this latter subtype is typically linked to an abnormal hormone secretion even at the early stage, facilitating its detection and diagnosis, PDAC is almost a symptom-free disease until metastases, or rather when the advanced stage leaves no longer chances of recovery ( Mpilla et al, 2020 ).…”

Prediction of Pancreatic Neuroendocrine Tumor Grading Risk Based on Quantitative Radiomic Analysis of MR

“…Based on histological differentiation (including mitoses and Ki-67 proliferation index), the WHO 2017 classification ( 4 ) has separated well-differentiated PNETs into three groups: low grade (G1), intermediate grade (G2), and high grade (G3). PNETs often cause severe morbidity due to excessive secretion of hormones (such as serotonin) and/or overall tumor mass, but in the clinic, lack of specific biomarkers inhibits early diagnosis ( 5 ). It was reported ( 6 ) that the PNETs grading was useful for therapeutic decisions and had a great impact on survival for PNETs ( 7 ).…”

Unilateral pseudouveitis revealing a pancreatic neuroendocrine carcinoma: A case report

“…Pancreatic neuroendocrine tumors (PNETs) are a heterogeneous group of tumors that arise from the endocrine tissues of the pancreas and comprise only 1%-2% of pancreatic tumors [1,2]. However, their incidence has significantly increased over the past few decades due to the improvement and the wide-spread use of diagnostic imaging [3] . Only 10% of all PNETS are associated with hereditary genetic endocrine tumor syndromes, other cases are sporadic [4,5].…”