European Journal of Cardio-Thoracic Surgery, Vol 12, 92-97, Copyright © 1997 by European Association for Cardio-thoracic Surgery
Characterization of pulmonary nodules and mediastinal staging of bronchogenic carcinoma with F-18 fluorodeoxyglucose positron emission tomography
RC Hagberg, GM Segall, P Stark, TA Burdon and MF Pompili
VA Palo Alto Health Care System, California 94304, USA.
OBJECTIVE: To evaluate F-18 fluorodeoxyglucose positron emission tomography
(PET) in terms of its sensitivity and specificity in diagnosing malignant
pulmonary nodules and staging bronchogenic carcinoma. METHODS: A
retrospective review of any patient that presented to the VA Palo Alto
Health Care System with a pulmonary nodule between 9/94 and 3/96 revealed
49 patients (four female, 45 male) age 37-85 (mean 63) with 54 pulmonary
nodules who had: chest CT scan, PET scan; and tissue characterization of
the nodule. Characterization of each nodule was achieved by histopathologic
(N = 44) or cytopathologic (N = 10) analysis. Of the 49 patients, 18 had
bronchogenic carcinoma which was adequately staged. Mediastinal PET and CT
findings in these 18 patients were compared with the surgical pathology
results. N2 disease was defined as mediastinal lymph node involvement by
the American Thoracic Society's classification system. Mediastinal lymph
nodes were interpreted as positive by CT if they were larger that 1.0 cm in
the short-axis diameter. RESULTS: Sensitivity and specificity for the
diagnosis of malignant pulmonary nodules using PET was 93 and 70%,
respectively. All nodules (N = 3) that were falsely positive by PET scan
were infectious in origin. All nodules (N = 4) that were falsely negative
by PET were technically limited studies (outdated scanner, no attenuation
correction, hyperglycemia) except for one case of metastatic
adenocarcinoma. The sensitivity and specificity of PET in diagnosing N2
disease was 67 and 100%, compared with 56% and 100% for CT scan (not
statistically significant). However, one more patient with N2 disease was
correctly diagnosed by PET than by CT scan. CONCLUSION: PET is a valuable
tool in the diagnosis and management of pulmonary nodules and may more
accurately stage patients with bronchogenic carcinoma than CT scanning
alone.