Hemorrhagic lesion on the chest wall after trauma.

A 59-year-old woman presented with a burning, rapidly progressive mass on the midchest, occurring after a fall 4 months prior. Examination found a large well-circumscribed mass over the lower xiphisternum (Figs 1 and 2). Results of baseline investigations were normal apart from mildly elevated liver function values. A computerized tomography scan confirmed a 6.4- x 4.9-cm lobulated soft tissue heterogeneous-density mass located in the subcutaneous fat with ill-defined borders and no obvious infiltration of the chest wall. A single focal abnormality was noted in the liver. Several incision/drainage procedures were complicated by difficulty achieving hemostasis. Ellipse incisional biopsy was performed (Figs 3 and 4).

Fig 1

Fig 2

Fig 3

Fig 4

Question 1: What is the most likely diagnosis?

Posttraumatic hematoma

Angiosarcoma

Hemangioma

Pyoderma gangrenosum

Pyogenic granuloma

Answers:

Posttraumatic hematoma – Incorrect. A simple hematoma would be likely to respond to incision and drainage and unlikely to progress over a 4-month period.

Angiosarcoma – Correct. Angiosarcoma is a rare and aggressive tumor of vascular endothelial origin. It has a poor prognosis and high rates of recurrence and metastases often to liver. A quarter of angiosarcomas occur in soft tissue.

Hemangioma – Incorrect. Hemangiomas are benign proliferations of endothelial cells usually associated with infancy or childhood, although hemangiomas can occur in adulthood, these acquired angiomas tend to be small and multiple (eg, cherry angiomas).

Pyoderma gangrenosum – Incorrect. Although pyoderma gangrenosum is painful, rapidly progressive, and associated with trauma and the clinical presentation can be variable, a purple undermined edge is typical. Vascular proliferation and abnormal vascular channels would not be seen histologically.

Pyogenic granuloma – Incorrect. Pyogenic granulomas present as shiny red nodules and can occur after trauma and bleed easily. They are usually less than 2 cm. On histology, there are distinctive lobular collections of capillaries, and they lack cellular pleomorphism or dissection of collagen fibers seen in angiosarcoma.

Question 2: Which immunohistochemical stain is most useful in identifying this lesion?

Desmin

S100 protein

EMA

CD-117

CD31

Answers:

Desmin – Incorrect. Desmin is a useful stain in identifying smooth muscle tumors as it confirms myogenic origin of tissues. It is not helpful in angiosarcoma diagnosis.

S100 protein – Incorrect. S100 is a useful marker in neural tissue and melanoma. The absence of S100 may aid the diagnosis of angiosarcoma if melanoma is a consideration.1, 2

EMA – Incorrect. Epithelial membrane antigen is a marker for adenocarcinomas and meningiomas rather than vascular tumors.

CD-117 – Incorrect. CD-117 or proto-oncogene c-Kit, is helpful in the diagnosis of gastrointestinal stromal tumors but not in angiosarcoma.

CD31 – Correct. Immunohistochemical markers are important in the diagnosis of angiosarcomas; they typically express CD31, CD34, von Willebrand factor, Ulex europaeus agglutinin 1, and vascular endothelial growth factor. CD31 is especially useful, as it is both highly sensitive and specific; it is particularly useful in poorly differentiated angiosarcomas.

Question 3: Which of the following is not a risk factor for this condition?

Human herpes virus 8

Klippel-Trenaunay syndrome

Radiation therapy

Post–breast cancer treatment

Milroy disease

Answers:

Human herpes virus 8 – Correct. Human herpes virus 8 does not have an established association with angiosarcoma.

Klippel-Trenaunay syndrome – Incorrect. Although most cases of angiosarcoma are thought to arise spontaneously, predisposing factors are well described. Klippel-Trenaunay syndrome is a rare congenital condition that affects the development of blood vessels, lymphatics, and soft tissues—associated chronic lymphedema predisposes to the development of angiosarcoma (Stewart-Treves syndrome).

Radiation therapy – Incorrect. Radiotherapy is an independent risk factor for angiosarcoma development, and the association is not exclusive to treatment of the breast.

Post–breast cancer treatment – Incorrect. Chronic lymphedema associated with breast cancer treatment is a risk factor for angiosarcoma as is chronic lymphedema of any aetiology.

Milroy disease – Incorrect. Milroy disease, a congenital condition that causes impaired lymphatic function, is another example of chronic lymphedema that predisposes to angiosarcoma development.