Vulvar lymphangiosarcoma in a bitch

ABSTRACT

Background: Lymphangiosarcoma (LSA) is a rare, highly malignant and infiltrative neoplasm of the lymphatic endothelium of dogs and cats. It is mostly reported in medium to large breed dogs, over 5-year-old, with no sexual predisposition. Affected animals present fluctuating and diffuse swelling, covering both dermis and subcutaneous tissue, spreading through lymphatic and haematic vessels. Histologically, LSA is characterized by connected channels devoid of conspicuous haematic elements. Treatment depends on location of the neoplasm, staging, and possibility of curative surgical excision. Chemotherapy and radiotherapy can increase survival time. In this report, we describe a rare case of vulvar LSA in a dog. This is the first Brazilian report of LSA in dogs so far.Case A 3-year-old, female, mixed breed dog was presented for evaluation of vesicle-bullous lesions in the vulvar and perivulvar region with progressive growth along 6 month. Histopathology revealed neoplastic proliferation in the superficial dermis, advancing through the profound dermis. The histological lesion pattern was consistent with angiosarcoma, which united along with macroscopic pattern of the tumor, and the presence of multiple anastomosed vascular structures without erythrocytes within it at microscopy, was compatible with LSA. No evidence of metastasis or lymphadenopathy was found on survey radiography and ultrasound. We performed a surgical excision, and remaining wound was reconstructed with an advancement skin flap. Despite wide surgical resection, neoplastic cells could be found in surgical borders, as well as a metastatic inguinal lymph node. Postoperative chemotherapy based on doxorubicin as a single agent was administrated. Disease free interval (DFI) was one month after surgery, when small bullous lesions were observed near the surgical site, and histopathological exam confirmed LSA...