Purpose: The aim of this study is to analyze retrospectively the computed tomography and magnetic resonance imaging (MRI) features of pediatric vaginal endodermal sinus tumor (EST) and rhabdomyosarcoma (RMS) in a case series.
Methods: Seven children with vaginal EST and 2 children with vaginal RMS underwent MRI and/or computed tomography examination before the biopsy and treatment. Images were evaluated by 2 observers for the following features: (a) tumor extent; (b) margin; (c) tumor shape; (d) tumor size; (e) architecture (solid, cystic, or mixed cystic-solid); (f) hemorrhage, necrosis, and calcification; (g) magnetic resonance T2 signal intensity; (h) pattern of the enhancement; and (i) signal intensity on diffusion-weighted imaging and apparent diffusion coefficient (ADC) value.
Results: All of the 7 ESTs showed as a round-shaped solid mass with a location limited to the vagina without vulva and bladder invasion, whereas RMSs have an irregular grape-like appearance filling the whole vagina with vulva and bladder invasion. The invasion to the cervix was not observed in EST or RMS. Both EST and RMS were heterogeneously hyperintense on T2-weighted magnetic resonance images and enhanced remarkably and heterogeneously. Heterogeneous high signal on diffusion-weighted imaging were observed in vaginal EST and RMS. The ESTs showed a lower ADC value (mean, 1.04×10 mm/s), while RMSs showed a relatively high ADC value (mean, 1.51 × 10 mm/s).
Conclusions: Computed tomography and MRI may be useful tools in diagnosing the vaginal RMS and EST.