Despite a global drop since the middle of the past century, gastric cancer remains the third most common cause of cancer-related deaths worldwide, and the fifth most common kind of cancer diagnosed globally [[1]](#one). The most frequent physical examination finding that indicates advanced illness is a palpable abdominal mass, also, non-specific weight loss, persistent stomach discomfort, dysphagia, hematemesis, anorexia, nausea, early satiety, and dyspepsia are the most typical presenting symptoms for gastric malignancies [[1]](#one), none of which were seen in our case of a patient presenting with solely respiratory complaints that later on, were discovered to be the product of a metastatic gastric adenocarcinoma. In our case, we introduce a 30-year-old male patient who presents with respiratory failure and ARDS in the emergency department, after several tests and continuous follow-up, the patient was discovered to have a widespread atypical lung adenocarcinoma from a metastatic gastric adenocarcinoma.