Pulmonary Large-Cell Neuroendocrine Carcinoma, a Multifaceted Disease—Case Report and Literature Review

<b>Background and Clinical Significance:</b> This article explores the complexity of large-cell neuroendocrine carcinoma (LCNEC) by presenting a clinical case involving a 17-year-old admitted for persistent wheezing, with no history of respiratory toxin exposure, a background of atopy, and a suspected diagnosis of bronchial asthma. Given the patient's age and the nature of the symptoms, the condition was initially diagnosed as asthma, leading to the initiation of maximum inhalation therapy. <b>Case Presentation:</b> Despite proper adherence and correct administration, symptoms persisted, necessitating the use of oral corticosteroids. Imaging revealed an extensive inhomogeneous mass in the cervical esophagus and trachea, along with a similar tumor in the right hilum, prompting bronchoscopy. The diagnosis of LCNEC was confirmed through imaging, histopathological findings, and a detailed immunohistochemical profile. Initially misdiagnosed as adenoid cystic carcinoma, this case highlights the diagnostic challenges and the importance of rigorous evaluation. <b>Conclusions:</b> It emphasizes that recurrent wheezing in adolescents is not always indicative of asthma and requires careful differential diagnosis to uncover less common causes.