Detection of Unsuspected Metastasis in a Melanoma Patient With Positron Emission Tomography

A 41-year-old obese woman had a nodular melanoma removed from the right calf 14 years ago. At the time of the diagnosis, she also underwent right inguinal lymph node dissection with no evidence of metastatic tumor. She presented with a new 2 cm mass just above the excision site on the calf wound. Fine needle aspiration was consistent with recurrent melanoma. Chest x-ray results were negative, and the patient had no clinical evidence of metastatic disease. Whole body PET images were obtained approximately 1 hour after injection of 10 mCi of F-18 FDG.