Refractory hypoxemic respiratory failure due to adenocarcinoma of the lung with predominant bronchioloalveolar carcinoma component.

Bronchioloalveolar carcinoma is a subtype of lung adenocarcinoma, characterized by well-differentiated cytology, peripheral location, and characteristic growth of neoplastic cells along intact alveolar septa (ie, lepidic growth pattern). Pure bronchioloalveolar carcinoma, by definition, doesn’t invade stroma, pleura, or lymphatic spaces. If there is lymphatic invasion, the tumor is classified as an adenocarcinoma, mixed subtype with predominant bronchioloalveolar carcinoma. Bronchioloalveolar carcinoma can present in various forms, including focal areas of increased lung opacity with ground-glass appearance (either as a single lesion or a confluence of lesions), or as a lobar consolidation mimicking bacterial pneumonia. We report an uncommon presentation of adenocarcinoma with predominant bronchioloalveolar carcinoma component, manifesting as multifocal pulmonary consolidation leading to refractory hypoxemic respiratory failure.