Imaging of diffuse fibroepithelial polyps on surgical free flap in oral cancer patients: two case reports

Fibroepithelial polyp (FEP) is a common benign tumor occurring in the skin and genitourinary tract, and there are no reports of multiple FEPs occurring on the myocutaneous flap. We report two cases of FEPs occurring diffusely on the skin tissue of the free anterolateral thigh flap after surgical reconstruction for oral squamous cell carcinoma. Clinically, multiple papillary nodules on the myocutaneous flap gradually increased. CT and MRI showed multiple papillary nodules on an enhanced layer covering the entire myocutaneous flap. PET/CT showed high uptake. One case was diagnosed with FEPs by surgery, the other by biopsy. The tumor-limited localization on the myocutaneous flap, characteristic morphology showing multiple papillary projection with an enhanced layer, and MRI signal showing patchy mild elevation of the apparent diffusion coefficient value may help in differential diagnosis from tumor recurrence or secondary carcinoma of the myocutaneous flap on diagnostic imaging.