18 F-FDG PET/CT in Pediatric INI1-Negative Soft Tissue Myoepithelial Carcinoma.

A 12-year-old girl with no previous comorbidities presented with a left gluteal swelling. 18 F-FDG PET/CT demonstrated heterogenous, moderate hypermetabolism localizing to a very large pelvic soft tissue mass with extension through the left greater sciatic notch into the left deep gluteal space. Core biopsy of the mass revealed INI1-negative myoepithelial carcinoma. Here we report the molecular imaging findings in an extremely rare pediatric case of INI1-negative, soft tissue myoepithelial carcinoma.