Not a Cyst: When a Cyst Obscures a More Nefarious Process

Angiosarcoma is an aggressive, malignant endothelial cell tumor of vascular or lymphatic origin, often arising on the head or neck of sun-damaged elderly patients. We present two cases in which the diagnosis of angiosarcoma was nearly obscured by the presence of an associated ruptured cyst or follicle. These cases serve as a reminder of the importance of careful and thorough evaluation of slides for additional diagnoses. It is important to remember that there can be more than one diagnosis in a biopsy to avoid the pitfall of missing a subtle background malignancy such as angiosarcoma.