Staging by positron emission tomography predicts survival in patients with non-small cell lung cancer

Abstract

Background: Positron emission tomography (PET) scanning is used increasingly to detect and stage lung cancer, but the test performance characteristics and relationship of PET to patient outcomes remain undefined.

Objective: To determine the test performance characteristics and relationship of PET scanning stage to patient outcomes relative to the 1997 International System for the Staging of Lung Cancer.

Design: Survival analysis using pathologic staging as the criterion standard for comparison of survival as predicted by staging by PET and CT.

Setting: University-based hospital.

Patients: All consecutive patients undergoing PET scanning for the evaluation of possible non-small cell lung cancer (NSCLC) during a 5-year period.

Main outcome measures: Long-term survival of patients with NSCLC after staging by PET.

Results: One hundred fifty-two thoracic PET scans were obtained for the staging of possible NSCLC during a 5-year period. One hundred twenty-three patients (81%) demonstrated increased (18)F-fluorodeoxyglucose uptake. The overall sensitivity and specificity of PET for detecting malignancy were 95% and 67%, respectively, compared with 100% and 27% for chest CT. PET and CT had similar accuracy for staging the overall extent of disease (91% and 89%, respectively). PET stage correlated highly with survival using either nodal location or overall stage (p = 0.003, p = 0.002), as did pathologic staging (p = 0.0001, p = 0.0001). CT scan results did not accurately predict survival (p = 0.608, p = 0.338).

Conclusion: PET scanning is a highly sensitive technologic advance in detecting and staging of thoracic malignancy and may more accurately predict the likelihood of long-term survival in patients with NSCLC than chest CT does.