Fig. 4
An elderly male (A–G) with low-level SUVmax (2.04) of mediastinal lymph node, low-level primary-tumor SUVpeak (3.34), low serum CEA (1.69 ng/ml) and high serum SCC (2.5 ng/ml). The primary tumor, which was confirmed as lung adenocarcinoma through operative pathological assay, is shown in 18F-FDG PET/CT maximum intensity projection (MIP) image (A), PET (B), CT (C) and PET/CT (D) images (arrows). The mediastinal lymph node in area 7, which was the highest-SUVmax (2.04) node in the mediastinum and proved to be negative by postoperative pathological analysis, was displayed in 18F-FDG PET (E), CT (F) and PET/CT (G) images (triangles)