First-line selpercatinib for a patient with RET fusion-positive pulmonary large cell neuroendocrine carcinoma

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is an uncommon variant of non-small cell lung cancer (NSCLC), known for its aggressive behavior. This includes rapid progression, widespread metastases, and resistance to conventional chemotherapy, all of which contribute to a dismal prognosis. Consequently, managing pulmonary LCNEC remains a significant challenge. In this case report, we describe the successful use of selpercatinib, , RET (rearranged during transfection) kinase inhibitor, as a first-line treatment in a patient with advanced pulmonary LCNEC harboring a RET fusion gene. Although RET fusion genes are exceedingly rare in pulmonary LC- NEC, this case underscores the importance of early genetic testing in patients with pulmonary LC- NEC to tailor targeted therapies effectively.