Everolimus in the Treatment of Neuroendocrine Tumors: Lights and Shadows

Abstract

Neuroendocrine tumors (NETs) comprise a heterogeneous group of neoplasms that originate from neuroendocrine cells, characterized by their ability to secrete hormones and peptides. Once considered rare, the incidence of NETs has steadily increased due to improved diagnostic modalities. The therapeutic landscape is multifaceted, ranging from surgery for localized disease to pharmacological interventions for advanced cases. However, the absence of robust predictive biomarkers precludes patient stratification and optimization of therapy. Everolimus, an oral mTOR inhibitor, has emerged as a key therapeutic agent due to its dual role in inhibiting cell proliferation and angiogenesis. Nevertheless, challenges such as resistance mechanisms, toxicity and optimal treatment sequencing remain unresolved. This article provides a comprehensive review of the role of everolimus in the management of NETs, focusing in particular on unresolved issues, from the absence of predictive biomarkers to the unavailability of defined guidelines for determining the correct therapeutic sequence.