Stewart-Treves syndrome (STS) is defined as angiosarcoma arising in the setting of chronic lymphedema. It is typically presented in breast cancer patients who underwent axillary dissection. A 79-year-old woman presented to our clinic with a wound that developed secondary to lymphedema. Pathologic examinations diagnosed the lesion as angiosarcoma. STS is a rare and deadly entity. It is hard to diagnose and has 10% mean survival rate for 5 years. We emphasize the importance of early diagnosis that can be a lifesaver.