Rhabdomyosarcoma (RMS) is a malignant neoplasm from stem cells, precursors of skeletal muscle, which is one of the most common soft tissue sarcomas in childhood. RMS can exist in any part of the body, but almost 30% of PMS is in the head and neck.The aim of this study was to analyze and describe the main radiological features of rhabdomyosarcomas of the head and neck region in children, and also to compareradiological features betweenembryonalandalveolarhistologicalrhabdomyosarcomas.

Inclusion criteria: patients withvisualization beforetreatment; diagnosis - rhabdomyosarcoma of head and neck region; age - from 0 to 18 years; visualization was made between the May 2012 year and December 2017 year. Head and neck scans were performed on GE Bright Speed CT-tomograph, Philips Achieva 3T and GE Signa Explorer 1,5T tomographs using contrast enhancement. Children youngerthan 5 years old were scannedunder general anaesthesiato prevent motion artefacts.

Our research contained 54 patients treated in the Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology and Immunology (Tbl.1). On CT images we evaluated characteristics of the x-ray density of a tumoron different phases of contrast enhancement: native – 34 ± 8 HU, 1CE - 49 ± 15 HU, 2CE – 60± 22 HU. Also, the involvement of near bone structures made up 70% and presence of calcinates was in 40% of cases. (Fig. 2) On MRI 83% of tumors were isointensive on T1 WI, 92% of...

This study shows typical radiological features of rhabdomyosarcomas of head and neck region in children. We also show that there are no differences between the histologicaltypes of RMS in ADC maps. In future, we want to find the correlation between patient's age, histological type and ADC.

Nataliia Strumila, researchassistant, a resident of radiology.nataliastrumila@gmail.com Alexey Krasnov, researcher. radiology@fnkc.ru GalinaTereshchenko, PhD, senior scientist. radiology@fnkc.ru

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