An uncommon presentation of a cutaneous angiosarcoma.

Cutaneous angiosarcoma (cAS) is a rare and aggressive malignant vascular tumor, which mostly occurs in the head and neck region. The outcome of cAS is poor and timely diagnosis is paramount, but often delayed because of the slow onset and the variance in presentation. This paper reports on a case of an 88-year old woman who presented with a persisting "hematoma" in the left retro-auricular region. Although considered at initial differential diagnosis, no signs of malignancy were identified in histopathology and imaging in the diagnostic work-up. At first, short-term follow-up showed no progression of the lesion. But 3 months after the first presentation additional biopsies were taken, because of rapid expansion of the lesion. The initial histopathological findings were most consistent with a benign vascular lesion, with signs of hemorrhage and reactive inflammation. However, the additional immunohistochemical analysis showed the presence of MYC oncoprotein, which confirmed the clinical suspicion of angiosarcoma. Because size and location of the lesion rendered complete resection unattainable, radiotherapy was commenced, but no significant volume reduction could be achieved. Therefore, palliative irradiation was initiated. The patient passed away 1 month later. Clinical diagnosis is often difficult and little is known about imaging of cAS. Histology and immunohistochemistry can be misleading, as cAS are easily mistaken for other lesions. Most studies report that multimodality treatment with surgery and radiotherapy is preferable, but this can be challenging in the head & neck region.