"Cutaneous Hemangiosarcoma - Benign Disease or Not?" TUMOR TIDBITS Volume 2; Number 10; June 15, 2001 Editor: Kevin A. Hahn, DVM, PhD, Dipl - ACVIM (Oncology) & Overall Nice Guy! CUTANEOUS HEMANGIOSARCOMA - BENIGN DISEASE OR NOT? OVERVIEW Skin hemangiosarcoma is a malignant tumor arising from endothelial cells. It is referred to as angiosarcoma or malignant hemangioendothelioma. Primary cutaneous hemangiosarcoma develops within dermal or subcutaneous tissues. The prevalence in dogs is 0.3-2.0%; median age 9 years (range, 4.5-15 years) and cutaneous hemangiosarcoma accounts for 14% of all hemangiosarcoma in dogs. Pit bull, boxer, and German shepherd dogs are affected more commonly than other breeds. It is rare in cats. SIGNS A solitary tumor is commonly noticed, although patient with cutaneous hemangiosarcoma can have multiple nodules clustered in one area. Dermal hemangiosarcoma appears as small, firm, raised, dark nodules located primarily on the prepuce and ventral abdomen. Subcutaneous hemangiosarcoma appears as firm or soft, fluctuant masses with associated bruising. These tumors are typically larger than dermal hemangiosarcoma and, although commonly located on the pelvic limbs, can arise in any location. Ulceration is frequent. Vascular stasis, radio therapy, trauma and sun exposure are predisposing factors in people and may be risk factors in dogs. DIFFERENTIAL DIAGNOSIS Trauma (i.e., subcutaneous hemangiosarcoma); Other tumors (i.e., mast cell tumor, melanoma, basal cell carcinoma and hemangioma). DIAGNOSTIC FINDINGS CBC abnormalities compatible with disseminated intravascular coagulation possible in patients with advanced or metastatic subcutaneous hemangiosarcoma. Thoracic radiographs may detect pulmonary metastasis,but results are typically normal at the time of diagnosis. Histopathologic examination is required to confirm the diagnosis and differentiate between dermal and subcutaneous hemangiosarcoma. Ture dermal hemangiosarcoma is well circumscribed and confined to the dermis. Subcutaneous hemangiosarcoma is poorly circumscribed and very invasive. TREATMENT Surgical excision is the treatment of choice. Because of size and invasive behavior, complete surgical excision of subcutaneous hemangiosarcoma is often difficult to achieve and requires aggressive surgical intervention. Chemotherapy is recommended after surgical excision of subcutaneous hemangiosarcoma in dogs and cats. These tumors have a high rate of metastasis. Treatment with adriamycin, cyclophosphamide, and vincristine has been shown to improve survival times in dogs and cats with aggressive hemangiosarcoma. Median survival time in dogs with complete surgical excision of a dermal hemangiosarcoma is 780 days. Metastasis to distant dermal sites occurs in 30% of patients. Median survival in dogs with subcutaneous hemangiosarcoma > 6 months but the behavior varies depending on the degree of invasion of the cancer. Metastasis to lungs, other cutaneous sites, and lymph nodes can occur. Median survival in cats with dermal or subcutaneous hemangiosarcoma is < 6 months with complete surgical excision due to the high rate of distant metastasis. Efficacy using chemotherapy after surgery is unknown due to the rare nature of the disease, but longer survival times are being reported in limited studies and local control rates in dogs and cats with incomplete excision are improved. COMMENTS At Gulf Coast Veterinary Oncology we recommend a thorough physical examination, survey radiographs of the chest and abdomen, complete abdominal ultrasound examination, and routine laboratory evaluations (a minimum data base) to rule out systemic illness, systemic neoplasia or metastasis, prior to the consideration of surgical, radiation, or chemotherapy options for dermal or subcutaneous hemangiosarcoma. For curative intent, the best plan is complete surgical excision followed by a combined use of Adriamycin, Vincristine, and Cytoxan for a duration of 4-6 months were regular exams to rule out metastatic behavior. MORE QUESTIONS? Don't hesitate to call or email us at Gulf Coast Veterinary Oncology! ALL THE BEST, Kevin. ==================================================== Kevin A. Hahn, DVM, PhD, Diplomate ACVIM (Oncology) & Overall Nice Guy Gulf Coast Veterinary Oncology 1111 West Loop South, Suite 150 Houston, TX 77027 713-693-1166 (V) 713-693-1167 (F) www.gcvs.com drhahn@g...