Purpose: Our objective was to determine if positron
emission tomography (PET) with fluorodeoxyglucose (FDG; PET-FDG)
imaging is equally efficacious in detection of metastases in small and
large mediastinal lymph nodes as compared to CT scanning.
Materials and methods: PET-FDG imaging, CT scanning, and
histology results of sampled mediastinal lymph nodes were compared in
54 patients of total 118 patients studied. Efficacy of PET and CT was
determined and compared in small (< 1 cm), intermediate (1 to 3 cm),
and large (> 3 cm) mediastinal lesions.
was accurate in 94% of patients in characterizing “N” disease as
compared to 61% with CT. Overall, sensitivity, specificity, and
accuracy of PET for staging mediastinal lymph nodes (n = 168 in 54
patients) was 96, 93, and 94%, as compared to 68, 65, and 66% with
CT. Positive and negative predictive value of PET in detecting
mediastinal adenopathy was 86% and 98%, as compared to 47% and 82%
with CT, respectively. PET was also highly reliable and accurate for
detecting lymph nodes < 1 cm, 1 to 3 cm, and > 3 cm in size with
superior efficacy than CT. Sensitivity, specificity, and accuracy of
PET for detecting malignancy in lymph node lesions < 1 cm in size was
97, 82, and 95%, respectively.
imaging is equally reliable and accurate for detecting disease in small
and large lymph node lesions in patients with suspected or proven lung
cancer with better efficacy than CT.