Angiosarcoma in children: the experience of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology and literature review
Authors: Zatsarinnaya O. S. , Toporkov M. A. , Andreeva N. A. , Teleshova M. V. , Utalieva D. T. , Stradomskaya T. V. , Shcherbakov A. P. , Grachev N. S. , Bolshakov N. A. , Sidorov I. V. , Konovalov D. M. , Nechesnyuk A. V. , Shamanskaya T. V. , Zhukov N. V. , Kachanov D. Yu. 
Published: January 2024

Angiosarcoma is a rare and highly malignant endothelial tumor, which occurs mainly in adults and is extremely rare in children and adolescents. The German guidelines for the treatment of soft tissue sarcomas provided by the Cooperative Weichteilsarkom Studiengruppe in 2012 included a separate therapeutic regimen for pediatric angiosarcoma consisting of a combination of vincristine/doxorubicin/cyclophosphamide (VDC) and paclitaxel. The aim of this article was to describe the epidemiological, clinical, and morphological characteristics of angiosarcoma, to review treatment approaches, and to present the experience of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology of Ministry of Healthcare of the Russian Federation in the treatment of children with angiosarcoma. Our study was approved by the Independent Ethics Committee and the Scientific Council of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology of Ministry of Healthcare of the Russian Federation. The study included 5 patients diagnosed with angiosarcoma who had received treatment between 2012 and 2022. The patients’ parents gave consent to the use of their child's data, including photographs, for research purposes and in publications. Data on the patients’ age, gender, tumor location and extension, performed treatment and outcomes of the disease were analyzed. The male:female ratio was 0.66:1 and the median age was 5.2 years. Tumors were located in the soft tissues (n = 3) and in the bones (n = 2). In all the cases, invasion of the surrounding tissues was observed. There were no distant metastases at the time of diagnosis. Two (40%) patients underwent primary resection (R1) and 3 (60%) patients had tumor biopsy. Four patients received therapy according to the German guidelines for the treatment of angiosarcoma (VDC/paclitaxel courses), and 1 patient received treatment according to the guidelines for the management of non-rhabdomyosarcoma soft-tissue sarcomas (courses with vincristine, ifosfamide, doxorubicin/ vincristine, ifosfamide, actinomycin D). Objective response to treatment was achieved in 3 (60%) cases. Local control treatment of these 3 patients consisted of radiation therapy with a total dose of 50.4 Gy after R1 resection in 2 cases and biopsy in 1 case. After a median follow-up of 32 months, 2 patients who had received VDC/paclitaxel were alive without events (with complete and partial response), 3 patients died of progressive disease. Our data confirm the aggressive behavior of angiosarcoma in children. Protocol therapy that includes multiagent chemotherapy based on paclitaxel and doxorubicin along with local control treatment makes it possible to achieve a long-term control of the disease in some patients. However, further research on molecular and genetic characteristics of angiosarcoma is required to find potential novel targets for molecular targeted therapy. Further studies investigating the effectiveness of checkpoint inhibitors in angiosarcoma are also needed.