Do We Need a New Diagnostic Model for Lung Cancer—Are We Ready? A Narrative Review of European Rapid Diagnostic Programs and an Operational Unified FTC-LCU Model

Background: Lung cancer (LC) remains the leading cause of cancer-related mortality worldwide. Survival outcomes are strongly stage-dependent. Many patients are diagnosed at advanced stages due to pre-clinical and diagnostic delays. While advances in imaging, bronchoscopic techniques, molecular diagnostics, and systemic therapies have improved individualized treatment, system-level delays continue to limit their impact. Aim of the study: The aim of this narrative review is a synthesis with an implementation-oriented framework proposal. Part I synthesizes the peer-reviewed literature, Part II presents an operational framework integrating a Fast Trac Clinic (FTC) and a network of Lung Cancer Units (LCUs) including proposed turnaround-time (TAT) goals. Methods: A narrative review of the literature of selected European policy documents addressing diagnostic delays, rapid-access lung cancer pathways, and coordinated care models was conducted. Results: European models demonstrate that structured referral criteria, centralized coordination, and predefined interval targets can achieve the first specialist assessment within 7–10 days and the completion of diagnostics within 21–28 days in optimized settings. Key determinants of timeliness include: direct primary care referral, parallel diagnostic processes, prioritized pathology and molecular testing, and multidisciplinary team (MDT) assessment. We propose operational TAT targets for chest CT, PET-CT, histopathology, NGS, PFTs, and MDT decision-making. Conclusions: Reducing avoidable diagnostic and therapeutic delays in LC requires a coordinated, system-level approach. A standardized FTC-LCU pathway with explicit TAT benchmarks, multidisciplinary governance, and digital support infrastructure may improve diagnostic efficiency, increase the proportion of patients treated at earlier stages, and enhance patient experience. Prospective evaluation of implementation impact on stage distribution and survival is advised.