Rationale: Lung cancer is the leading cause of cancer-related death in the world. Tyrosine kinase inhibitors (TKIs), which target mutated epidermal growth factor receptor (EGFR), have been the first-line treatment of late-stage lung adenocarcinoma harboring EGFR mutation. EGFR mutations are mostly identified in lung adenocarcinoma. However, it is rarely seen in lung neuroendocrine carcinoma, and treatment strategies remain under reported.
Patient concerns: Here, we describe a 54-year-old Chinese man diagnosed with lung adenocarcinoma (cT4N3M1b, stage IV) with neuroendocrine differentiation and L858R mutation on exon 21. He developed progressive disease in liver 4 months later, and the biopsy of liver metastases showed neuroendocrine carcinoma maintained the same EGFR mutation.
Diagnoses: Lung adenocarcinoma and neuroendocrine carcinoma were identified by biopsy.
Interventions: After a combined treatment with nab-paclitaxel and erlotinib, the patient achieved partial remission.
Outcomes: The patient's overall survival was 27 months.
Lessons: This case highlights that EGFR mutated lung neuroendocrine carcinoma is not responsive to single-agent EGFR-TKI. However, combined application with nab-paclitaxel can improve its efficacy and prolong the patient's survival.