We report a case of a 59-year-old man with testicular germ cell tumor who showed new hypermetabolic lesions at the left axillary lymph nodes on a post-treatment positron emission tomography-computed tomography (PET-CT) scan. The hypermetabolic lesions were found to be caused by an influenza vaccination 10 days prior to the PET-CT scan and disappeared without additional treatment. To date, he is alive with complete remission.
Antineoplastic Combined Chemotherapy Protocols/therapeutic use ; False Positive Reactions ; Humans ; Influenza Vaccines/*administration & dosage/adverse effects ; Injections, Intramuscular ; Lymph Nodes/drug effects/*radiography/*radionuclide imaging ; Male ; Middle Aged ; *Positron-Emission Tomography ; Predictive Value of Tests ; Seminoma/*diagnosis/drug therapy/pathology/radiography/radionuclide imaging ; Testicular Neoplasms/*diagnosis/drug therapy/pathology/radiography/radionuclide imaging ; *Tomography, X-Ray Computed ; Treatment Outcome ; *Whole Body Imaging