Angiosarcomas are malignant tumors of the vascular endothelium and are typically idiopathic. These tumors comprise 2% of all soft tissue sarcomas and have an estimated incidence of 2 per million. 1,2 Known causes of angiosarcoma include genetic syndromes—such as von Hippel- Lindau, Chuvash polycythemia, Bannayan- Riley-Ruvalcaba, Cowden, and hamartomatous polyposis syndromes— chronic lymphedema, and exposure to radiation. 3 Vinyl chloride, arsenicals, and thorotrast are known to increase the incidence of liver angiosarcoma. 4
Malignant transformation of hemangioma is rare. We describe metastatic angiosarcoma in a patient with a large, longterm treatment-resistant subcutaneous hemangioma, illustrating such a possibility. We review similar cases and discuss the value of determining pathogenesis in such patients.
Case Presentation and Summary
A 55-year-old female with a long-standing childhood hemangioma of the left lower extremity was referred to Ochsner Medical Center for tissue diagnosis of new pulmonary nodules. Her medical history included a 7 pack-year smoking history; she had quit 3 years prior. Her family history included a sister who died from breast cancer. The patient initially had a progressive, intermittently bleeding tumor in the left foot at age 7. She was diagnosed with hemangioma in her twenties. At that point, her tumor began to involve the posterior calf and femur, causing deformity. She had multiple surgical resections but reportedly all pathology demonstrated benign hemangioma. She received radiation for pain, a routine treatment at the time, but developed a focus of progression in the heel. Above-knee amputation was considered but could not be performed when hemangioma was discovered in the hip area. She was lost to follow-up between 2001 and 2015. Lower extremity magnetic resonance imaging in 2015 was stable with imaging prior to 2001. A repeat biopsy in 2016 demonstrated hemangioma. The patient then received radiation to a wider field, including the femur, with minimal response. She completed a course of steroids as well. Bevacizumab was started in 2017 and improved foot deformity. She also briefly trialed pazopanib for 4 weeks in 2018 in an attempt to switch to oral medications. Despite partial response, she discontinued both agents in July 2018 because of toxicity and the burden of recurrent infusions.
Four months later, she presented with 2 months of intermittent hemoptysis and 18 months of metallic odors. Additionally, she lost 25 pounds in 3 months, which she attributed to a diet plan. At this visit, her left lower extremity exhibited multiple subcutaneous tumors and nodules.
Computed tomography (CT) with contrast demonstrated innumerable pulmonary nodules, the largest measuring 2.2 cm in the right lower lobe superior segment. Positron emission tomography (PET)/CT revealed 2 nodules with mild hypermetabolic activity; the largest nodule had a maximum standardized uptake value of 2.7. Bronchoalveolar lavage studies showed intra-alveolar hemorrhage with hemosiderin-laden macrophages. No malignancy, granuloma, or dysplasia was found in transbronchial needle aspirate of the largest nodule. The patient had no lymphadenopathy.
At this hospital, surgical resection by video-assisted thoracoscopic surgery confirmed multifocal malignant epithelioid neoplasm suspicious for angiosarcoma. Multiple areas showed proliferation of atypical epithelioid-to-spindle cells. There were prominent associated hemosiderin-laden macrophages, fresh red blood cells, and dilated blood-filled spaces. Cells demonstrated hyperchromasia with irregular nuclear contours, prominent nucleoli, and mitoses ( FIGURE 1 ). Additionally, there were areas of focal organizing pneumonia. For atypical cells, staining was CD31-positive and CD34-negative. Staining was strongly positive for ERG. There was increased Ki-67 with retained INI expression and patchy weak reactivity for Fli-1.