A 78-year-old male patient who had received six courses of nivolumab for recurrent gastric cancer and direct oral anticoagulants for paroxysmal atrial fibrillation visited our hospital for progressive dyspnea. Chest high-resolution computed tomography (HRCT) showed ground glass opacities bilaterally around the hila of the lungs. The presence of antiphospholipid antibodies and deep vein thrombosis raised the suspicion of catastrophic antiphospholipid syndrome (CAPS).
The patient died on day 16 of hospitalization due to respiratory failure despite the intravenous administration of methylprednisolone pulse therapy, high-dose immunoglobulin, and low molecular-weight heparin. Postmortem CT, also known as autopsy imaging, revealed several cerebral infarctions. Diffuse alveolar damage (DAD), alveolar hemorrhage, and multiple pulmonary embolisms were also identified on postmortem examination, and CAPS was diagnosed on the basis of these findings. The present case suggests that CAPS may be one of the adverse effects of nivolumab therapy.