[A Case of Multiple Primary Pulmonary Neuroendocrine Carcinoma
with EML4-ALK Fusion Gene Positive].

Neuroendocrine carcinoma (NEC), a subtype of neuroendocrine tumors with high proliferative activity, is characterized by strong invasiveness and poor prognosis. This article reports a previously healthy female non-smoker who developed NEC occurring sequentially in different lobes of both lungs. The lesions were pathologically diagnosed by hematoxylin-eosin (HE) staining as large cell neuroendocrine carcinoma (LCNEC) and small cell lung cancer (SCLC), respectively. Next-generation sequencing (NGS) performed on both lesions revealed the presence of echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion mutations in both lesions. Notably, the patient achieved a significant therapeutic response to ALK-tyrosine kinase inhibitors (TKIs) targeted therapy. .