Computed Tomography (CT) Features of Pelvic Rhabdomyosarcoma (RMS) in Children

Background: Currently, there are few literature reports on the CT features of pelvic rhabdomyosarcoma, most of which exist in the form of case reports, and some literature reports have suggested that CT features of pelvic rhabdomyosarcoma lack specificity. This study was designed to investigate the CT features of pelvic RMS in children to provide imaging evidence for clinical diagnosis.

Methods: We retrospectively reviewed radiographic and clinical data of all paediatric patients with pelvic neoplastic lesions pathologically proven to be malignant in our hospitals from January 2012 through March 2021. The data of the included paediatric patients were divided into two groups according to whether the pathology results indicated RMS. CT features of RMS (n = 37) and non- RMS (n = 91) were compared by two abdominal radiologists.

Results: A total of 9 CT features were statistically significant for the diagnosis of pelvic RMS in children (p < 0.05). The sensitivity (range, 0.64-0.74) and specificity (range, 0.86-0.93) of the CT features showing multinodular fusion, surrounding blood vessels, and heterogeneous progressive centripetal enhancement were both relatively high. The CT features indicating lower than muscle density, necrosis, non-calcification and non-haemorrhage exhibited high specificity (range, 0.86-0.97), but the sensitivity (range, 0.32-0.40) was relatively low, while the sensitivity (range, 0.37-0.46) and specificity (range, 0.75-0.83) of other CT features used for diagnosing pelvic RMS, namely, lobulated and lymphatic metastasis, were both relatively low.

Conclusion: Pelvic rhabdomyosarcoma in children has its own specific CT features.