Diffuse Alveolar Hemorrhage as the Initial Presentation of Hepatic Adenocarcinoma: A Case Report

Diffuse alveolar hemorrhage (DAH) is a life-threatening condition resulting from bleeding into the alveolar spaces. It is typically associated with autoimmune vasculitis, infections, drugs, or cardiac disease. Malignancy-related DAH is rare, and cases linked to hepatic adenocarcinoma are extremely uncommon. We report the case of a 66-year-old male with progressive respiratory failure, severe hypoxemia, and bilateral diffuse alveolo-interstitial infiltrates. Infectious, autoimmune, and cardiac investigations were non-contributory. Chest CT angiography revealed massive DAH. Incidentally, multiple hepatic nodules were identified, and ultrasound-guided biopsy confirmed hepatic adenocarcinoma. The DAH represented an unusual paraneoplastic or metastatic pulmonary manifestation of the tumor. Although liver cancer frequently metastasizes to the lungs, DAH as its first clinical manifestation is exceptional. Potential mechanisms include fragile tumor-induced neovascularization, pulmonary tumor emboli causing vascular injury, or paraneoplastic immune-mediated capillaritis. Only isolated cases are reported. In elderly patients with unexplained DAH, especially when constitutional symptoms or extrapulmonary lesions are present, underlying malignancy including hepatic adenocarcinoma should be considered. Early histological sampling is crucial for diagnosis and management.