Lung carcinoids (lung neuroendocrine tumors): integrated classification, molecular biology, diagnosis, and multidisciplinary management

This narrative review written by experts aims to provide a comprehensive synthesis of current knowledge and guidelines on lung carcinoids, emphasizing the multidimensional approach required for effective diagnosis and management. The manuscript will: i) Define and classify lung carcinoids in accordance with the latest WHO classification system, and emphasize the importance of molecular markers for precise subtyping; ii) Analyze epidemiological trends, discuss prevalence, incidence, and mortality rates, alongside key risk factors including genetic predispositions (MEN1) and precursor lesions such as diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH); iii) Investigate the etiology and carcinogenesis of lung carcinoids, including insights into the molecular hallmarks and pathways that underlie tumor development and progression; iv) Detail clinical presentations, distinguishing pulmonary symptoms from secretory syndromes (carcinoid syndrome and Cushing's syndrome), supported by visual aids to elucidate symptom prevalence and implications; v) Present an integrated diagnostic approach, encompassing state-of-the-art imaging modalities (CT, MRI, 68Ga-SSA-PET-CT) and advanced molecular pathology techniques; vi) Outline evidence-based treatment strategies, addressing early-stage interventions, systemic therapies, locoregional therapies, and emerging modalities such as immunotherapy and agnostic approaches; vii) Explore the role of multidisciplinary management, highlighting the critical importance of tumor boards dedicated to lung carcinoids and provide a checklist of key items for comprehensive case discussion and decision-making; viii) Conclude with future perspectives, identifying gaps in current knowledge and suggest directions for research to enhance diagnosis, treatment, and overall patient quality of life.