Periprosthetic seroma with false-positive FDG PET-CT reactive nodes mistaken for metastases in a patient previously treated of metastasic melanoma. Potential source of diagnostic errors.

FDG PET/CT is believed to be crucial in oncology, but its limited specificity represents a challenge. Prosthetic meshes used for repair abdominal defects may lead to false-positives FDG PET/CT uptake, over staging malignancies and inducing inappropriate treatments. A false-positive FDG PET/CT uptake mimicking metastatic disease during the follow-up of a previously treated metastatic melanoma patient is presented.