[Case of Lung Cancer with High-Grade Fetal Lung Adenocarcinoma Components Treated with Chemotherapy].

A woman in her 70s presented to our hospital with complaints of cough and dyspnea. Computed tomography(CT) images showed a large amount of left pleural effusion, pleural tumors, and mediastinal lymphadenopathy. Left thoracic drainage was performed, and high-grade fetal lung adenocarcinoma was suspected upon pleural effusion-cell block immunostaining. Pathological evaluation of the CT-guided biopsy specimen provided a diagnosis of carcinoma with high-grade fetal lung adenocarcinoma. Although the tumor progressed rapidly, chemotherapy with atezolizumab/bevacizumab/carboplatin/ paclitaxel was highly effective. However, subsequent maintenance therapy with atezolizumab/bevacizumab led to disease progression.