Lung cancer is the most frequent cause of cancer deaths in the western world today. In our case, we present the history of a 62-year-old man with the diagnosis of the uncommon complication of an acute gastric pneumatosis following his palliative chemotherapy. This rare condition was first described more than 100 years ago and has since been described in several distinctive clinical settings. To our knowledge, we present the first case of chemotherapy-related pneumatosis exclusively limited to the stomach wall but involving the portal veins and the spleen.