False-Positive F-18 FDG PET/CT From Foreign Body Reaction on Anterior Chest Wall After Endoscopic Total Thyroidectomy via Axillo-Breast Approach for Thyroid Cancer Two Case Reports

Abstract

Endoscopic thyroidectomy is becoming a popular method for the treatment of low-risk micropapillary thyroid cancers. Here, we report 2 cases showing increased uptake on postoperative follow-up FDG PET/CT imaging in the chest wall after endoscopic thyroidectomy via axillo-breast approach without gas insufflations. An ultrasound-guided gun biopsy was performed to rule out metastasis. The histopathology revealed granulomas caused by foreign body reaction, presumably because of the port pressure of the surgical instruments. These lesions are of clinical importance because they can cause misinterpretation of the imaging findings in patients undergoing postoperative FDG PET/CT surveillance for tumor recurrence and can lead to unnecessary treatment.