A 59-year-old man with hypertension and Crohn's disease that was complicated by fistulas was found unconscious at home. He was being treated with infliximab administered through a central venous access device, which had been placed for long-term intermittent treatment. The patient had been treated unsuccessfully with sulfasalazine, glucocorticoids, and immunomodulatory therapies, including methotrexate, azathioprine, and mercaptopurine. He was intubated and brought to the emergency department. Vital signs were stable, and the physical examination was notable for cyanosis of the head, neck, upper torso, and arms. Venography showed occlusion of the superior vena cava, a finding consistent with the superior vena cava syndrome (SVCS). Ultrasound-accelerated thrombolysis was performed along with bare-metal stenting of the superior vena cava, which alleviated the obstruction. After 2 weeks of hospitalization, the patient recovered with only residual visual impairment in the right eye (20/200) as a result of prolonged congestion of the retinal veins. SVCS is often due to external compression from cancers (e.g., cancers of the lung and lymphomas) but may be caused by intravascular thrombosis associated with the placement of a central catheter. A 21-year-old woman presented to the emergency department with an 8-month history of progressive swelling and pain in the right thigh. Magnetic resonance imaging of the right leg revealed a large, enhancing, circumferential periosteal femoral mass that measured 30 cm in the craniocaudal dimension, as well as a nonocclusive thrombus in the right femoral vein, for which the patient received anticoagulation. Biopsy of the femoral mass confirmed a diagnosis of chondroblastic osteosarcoma. One week later, the patient had shortness of breath and left pleuritic chest pain. The oxygen saturation was 94% while the patient was breathing ambient air. Chest radiography revealed innumerable lesions in both lungs (Panel A). Computed tomography of the chest confirmed the presence of extensive, lobulated, and partially calcified nodules and masses throughout both lungs, a finding suggestive of pulmonary metastases (Panel B). Despite the initiation of chemotherapy, the disease progressed. A second chemotherapy regimen was started; five cycles have been completed, and the disease is currently stable.