Differentiation of Reactive Lymph Nodes and Tumor Metastatic Lymph Nodes With 68Ga-FAPI PET/CT in a Patient With Squamous Cell Lung Cancer.

ABSTRACT: False-positive findings of mediastinal lymph node often confound the image interpretation of the preoperative PET/CT in non-small cell lung cancer. In this case, we reported 18F-FDG and 68Ga-FAPI PET/CT findings in a patient with squamous cell lung cancer. 18F-FDG-based TNM stage was stage IIIA (T1bN2M0) due to increased uptake in the enlarged right lower paratracheal lymph node. However, no abnormal 68Ga-FAPI uptake was observed in this lymph node. Subsequent histopathological examination revealed no evidence of malignancy in the mediastinal lymph nodes. Therefore, the tumor stage was downstaged to stage IA (T1bN0M0), which was in accordance with 68Ga-FAPI-based TNM stage.