Abstract
Primary pulmonary mucinous adenocarcinoma is an unusual histological type of non-small cell lung cancer and has a rare prevalence at a young age. There is no standard first-line therapy for advanced primary pulmonary mucinous adenocarcinoma in children and young adults-this study reports two rare cases of primary pulmonary mucinous adenocarcinoma with wild-type anaplastic lymphoma kinase and epidermal growth factor receptor (EGFR) genes. One is a 13-year-old boy (Case#1), and another is a 27-year-old male (Case#2). Both two cases were treated with antibiotics for suspected pulmonary infection. In our hospital, they were diagnosed with advanced primary pulmonary mucinous adenocarcinoma, the Eastern Cooperative Oncology Group (ECGO) performance status was three scores. We chose pembrolizumab and chemotherapy plus angiogenesis inhibitors for Case#1 and Case#2. The two patients' symptoms improved and presented with a partial response according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria，the scores of ECOG performance status were two for Case#1 and one for Case#2. This study illustrates a promising outcome for advanced primary pulmonary mucinous adenocarcinoma with immunotherapy and chemotherapy plus angiogenesis inhibitors at a young age.