Staging and managing lung tumors using F-18 FDG coincidence detection

Fluorine-18 fluorodeoxyglucose (F-18 FDG) positron emission tomographic (PET) imaging can be a vital tool in the evaluation and preoperative staging of pulmonary neoplasms. Imaging studies on the gamma camera using coincidence PET (co-PET) were introduced recently into clinical practice. This prospective study assessed the efficacy of co-PET for identifying primary tumors, mediastinal lymph node involvement, the presence of distant spread, the effect on disease staging, and influence on disease management.

Sixty consecutive patients with 61 lung tumors were enrolled in the study (36 men, 24 women; age range, 32-87 years; mean age, 67 years). Histopathologic confirmation was obtained in 58 patients (59 tumors).

In assessments of a primary lesion to establish its malignant or benign nature, the sensitivity rate of co-PET was 96% (53 of 55 lesions), the specificity rate was 83% (5 of 6 lesions), and the accuracy rate was 95% (58 of 61 lesions). In the co-PET assessment of lymph node involvement in which histopathologic confirmation was obtained (n = 32), the sensitivity rate was 89% (8 of 9 lesions), the specificity rate was 91% (21 of 23 lesions), and the accuracy rate was 91% (29 of 32 lesions). Previously unknown distant metastases were correctly identified in eight patients, but five false-positive lesions were detected in the brain. Disease staging was correctly altered in 20 patients (33%), and disease management plans were changed in 20 patients (33%) based on the co-PET findings. Unnecessary surgery was obviated in six patients (10%). One patient was given the chance for curative treatment based on the findings of the co-PET study.

The evaluation of patients with lung neoplasms using F-18 FDG coincidence detection appears to be reliable.