A 74-year-old woman comes to the emergency department because of painful swelling and multiple purple ulcerated nodules on her right upper extremity. The patient has a history of chronic swelling in her right upper extremity with a gradual increase in size over the past 5 years. 13 years ago, she was diagnosed with right-sided breast carcinoma and underwent a modified radical mastectomy. Her surgery was followed by radiation and treated for 5 years with a selective estrogen receptor modulator. She has type 2 diabetes mellitus, hypertension, and atrial fibrillation. She lives with her husband and volunteers at a local hospital. She has a family history of breast carcinoma. She does not smoke, drink alcohol, or use illicit drugs. Current medications
