Thymic carcinoma presenting with cardiac tamponade and superior vena cava invasion

We present the case of a woman in her 40s who presented with progressive shortness of breath, facial flushing, tachycardia that worsened when supine and bilateral leg swelling. Initial evaluation included a chest X-ray, which revealed widened mediastinum and a transthoracic echocardiogram with evidence of cardiac tamponade. A pericardiocentesis was performed, draining 900 mL of haemorrhagic fluid. Subsequent CT imaging identified a large anterior mediastinal mass invading into the superior vena cava (SVC) and extending towards the right atrium. A needle biopsy confirmed the diagnosis of thymic carcinoma. The patient remained stable and was started on chemotherapy. This case highlights the importance of considering SVC invasion in patients presenting with cardiac tamponade and mediastinal masses, particularly when positional symptoms such as orthostatic tachycardia and facial flushing are present.