Soft tissue myoepithelial carcinoma-a case report with molecular and electron microscopic analysis

Myoepithelial tumors are rare neoplasms that primarily occur in the salivary gland but over the last decade have also been described in other locations, including soft tissue. Myoepithelial carcinoma of soft tissue has shown to have a recurrence rate of 39-42% and distant metastases in 32-53% of patients. The only known predictor of malignancy in soft tissue myoepithelial tumors described is cytologic atypia. There are no other validated criteria for differentiating benign and malignant tumors, neither for grading nor for standard of care for these tumor types. Herein, we present a case of myoepithelial carcinoma of inguinal soft tissue in a 37-year male. We also describe the molecular and previously sparingly described detailed electron microscopic features of this case.