Case 85 - Discussion

Uploaded: 2007-08-29, Updated: 2007-10-25

   

CD31, 40× CD31, 40×
CD34, 20× CD34, 40×
CD34, 40× Factor VIII, 20×
Factor VIII, 40× Factor VIII, 40×
Factor VIII, 40× Ki67, 20×
   
The patient died two months later after the diagnosis.
   
  Angiosarcoma of the Scalp
 

Cutaneous angiosarcoma primarily affects elderly patients and is commonly located on the head and neck, especially the scalp. Currently, angiosarcoma of the scalp in elderly patients is recognized as a unique subtype that is also known as senile angiosarcoma or malignant angioendothelioma (1-3). It commonly occurs in elderly white men with a male-to-female ratio of 3:1 (1, 3). The predisposing factor for the angiosarcoma of the scalp is uncertain, although chronic lymphoedema has been widely recognized in women following radical mastectomy. The most frequent association with angiosarcoma of the scalp is probably prior radiation for either a malignant or benign condition.

Clinically, angiosarcomas of the scalp have a variety of presentations. Most cases start as ill-defined bruise-like lesions with an indurated border and are frequently clinically innocent. The lesions may be single or multifocal, blue or violaceous, and raised or flat. In advanced stage, the tumors are typically large, ill-demarcated with elevated, multinodular blue-red appearance. Hemorrhage and ulceration are frequently seen. The cut surface usually shows microcystic or spongy architecture with extensive infiltration of the surrounding tissue. Therefore, it is difficult to determine the extent of the tumor clinically. In our case, the patient presented with as an unusual swelling cystic lesion, which misled the clinicians make a diagnosis of sebaceous cyst with infection.

Microscopically, the classic angiosarcoma is composed of a disorganized vascular or sinusoidal anastomosing network with infiltration in the dermis, and the neoplastic slit-like vessels commonly dissect the dermal collagen. The tumor cells are polyhedral atypical endothelial cells with high nucleus to cytoplasm ratio and scant amphophilic cytoplasm. The tumor in our case shows these typical features. Several histological variants of angiosarcoma are noted that include the spindle type, solid epithelioid type, hemangioma-like type, granular cell variant and pleomorphic type (4).

Several benign and malignant tumors are among the differentiation diagnoses. Hobnail hemangioma, also named targetoid hemosiderotic hemangioma or atypical hemangioma, may show arrays of angulated vascular channels in the dermis with dissection of the collagen bundles, and the tumors also have papillary projections into the vascular lumen lined by neoplastic endothelial cells in a hobnail pattern. All these features are similar to those in classic angiosarcoma. However, hobnail hemangioma usually develops on the skin of the extremities in young adults, and microscopically it shows distinct biphasic appearance composed of a superficial portion with dilated vessels and a deeper portion with attenuated slit-like capillaries. The tumor cells in hobnail hemangioma show bland nuclear features, low proliferative rate and often abundant hemosiderin-laden macrophages. All features described above are against a malignant diagnosis. Papillary endovascular angioendothelioma may be confused with angiosarcoma, but it is an intravascular lesion and angiosarcoma is almost never confined to a vascular lumen. Spindle cell angiosarcoma often resembles Kaposi’s sarcoma histologically, but these two lesions usually differ substantially in clinical features, and Kaposi’s sarcoma but not spindle cell angiosarcoma is often positive for HHV8. Epithelioid angiosarcoma may mimic other epithelioid tumors, including angiomatoid squamous cell carcinoma, melanoma, epithelioid leiomyosarcoma and clear cell sarcoma. Pleomorphic angiosarcoma can be confused with atypical fibroxanthoma, undifferentiated carcinoma, melanoma and malignant fibrous histiocytoma. Immunostains as well as electron microscopy and cytogenetic analyses are very important in differential diagnosis of these tumors.

Angiosarcoma of the scalp is difficult to treat clinically, and a combination of surgical resection with a wide and deep margin and radiation has been recommended (5). Recently, chemotherapy using docetaxel has been showing good efficacy in angiosarcomas of the scalp (6). Surgery alone is often not feasible because of the multifocal nature and local spread pattern of these tumors. Frequently during surgery, the extent of the tumors is very difficult to determine due to the extensive microscopic spread. Therefore, intraoperative frozen specimens are often necessary to assess the margins.

The prognosis for patients with angiosarcomas of the scalp is poor, and these tumors have a tendency for local recurrence and metastasis by lymphatic or hematogenous routes. In our case, the patient is highly suspicious of cervical lymph node metastasis. Clinical studies showed that the most important factor in determining prognosis is probably the size of tumor, and tumors less than 5 cm are associated with a significantly better prognosis than larger lesions. Therefore, it is very important for the clinicians and the pathologists to make an accurate diagnosis initially and give the patient prompt treatment.

   
REFERENCES
 
  1. Mark RJ, Poen JC, Tran LM, et al. Angiosarcoma: a report of 67 patients and a review of literature. Cancer. 1996; 77: 2400-2406.
  2. Cutaneous Angiosarcoma. William M. Mendenhall, Charles M. Mendenhall, John W. Werning, John D. Reith, and Nancy P. Mendenhall. Am J Clin Oncol 2006;29: 524–528.
  3. A 14-year retrospective review of angiosarcoma: clinical characteristics, prognostic factors, and treatment outcomes with surgery and chemotherapy. Fury MG, Antonescu CR, Van Zee KJ, Brennan MF, Maki RG. Cancer J. 2005 Jul-Aug; 11(4):354. (PMID: 16053668)
  4. Nonmelanocytic Tumors of the Skin. James W. Patterson and Mark R. Wick. AFIP Atlas of Tumor Pathology, Series IV, Fascicle 4. 2006
  5. Calonje E, MacKie RM. Soft tissue tumours and tumour-like conditions. In: Burns T , Breathnach S , Cox N , Grifiths C , eds. Rook's Textbook of Dermatology. 7th ed. Oxford: Blackwell Science Ltd; 2004: 53.28-53.30.
  6. Tohru Nagano, Yozo Yamada, Tetsuya Ikeda, Haruhisa Kanki, Tsuneyoshi Kamo, Chikako Nishigori. Docetaxel: A therapeutic option in the treatment of cutaneous angiosarcoma. Cancer 2007;110:648–51. (PMID: 17582627)