[Alectinib and mixed large cell neuroendocrine carcinoma of the lung.]

The treatment of mixed large cell neuroendocrine carcinoma is less studied due to its low incidence. However, the presence of anaplastic lymphoma kinase (ALK) fusion gene is rare in such tumours, ALK inhibitors may represent a promising therapeutic option instead of cytostatic therapy. Routine chest X-ray and then computed tomography (CT) examination revealed a pulmonary tumour in a 52-year-old asymptomatic woman. The neoplasm was removed by lobectomy. Histological examination confirmed papillary predominant lung adenocarcinoma. The patient was treated with postoperative chemotherapy and irradiation. 3 years later, neurologic symptoms were observed, therefore, brain CT was performed. The evaluation confirmed brain metastases which were removed. Histological examination identified metastasis of large cell neuroendocrine carcinoma. Revision and molecular examination of the metastasis and lung specimen revealed pulmonary mixed large cell neuroendocrine carcinoma with ALK-rearrangement. Alectinib (Alecensa) treatment was initiated resulting in regression of the previously observed liver metastases. Progression has not occurred in the last 3 years since the start of treatment. Detection of ALK fusion genes and research of ALK inhibitor therapy focus primarily on lung adenocarcinomas. Our case report would like to draw attention to the evaluation of driver mutations in pulmonary mixed neuroendocrine carcinoma with adenocarcinoma component because targeted treatment may be an effective alternative. Orv Hetil. 2023; 164(14): 548-554.