First-Line Therapies for Metastatic Lung Adenocarcinoma Without a Driver Mutation. 
Lung cancer is the leading cause of cancer-related death worldwide.  The majority of these cancers are non-small-cell lung cancer, of which adenocarcinoma is the most common histologic subtype.  Most patients are diagnosed at advanced stages when systemic treatment is needed.  Whereas prognosis has improved for patients with targetable driver mutations, the majority of patients do not possess tumors with such molecular mutations.  Platinum-based chemotherapy has traditionally been the mainstay of treatment, although in recent years immunotherapy has emerged as a treatment option and can result in robust and durable treatment responses in a subset of patients.  Recent clinical trials on novel immunotherapy combinations and immunochemotherapy combinations may broaden the number of patients that may benefit from checkpoint inhibitors and elicit responses in those who otherwise may not have experienced a response to monotherapy with an immunotherapy drug.  This review will outline the currently available therapies for the first-line treatment of metastatic adenocarcinoma that do not possess a driver mutation and provide a recommended approach and algorithm by which to select the best first-line therapy.