Utility of Routine PET Imaging to Predict Response and Survival After Induction Therapy for Non-Small Cell Lung...

Data from clinical trials suggest that changes in the glucose avidity of the primary site of lung cancer during induction therapy, measured by changes in (18)F-fluorodeoxyglucose positron emission tomography, correlate with tumor response. Little information about the utility of changes in positron emission tomography imaging of involved lymph nodes during induction chemotherapy is available. The utility of positron emission tomography imaging of either the primary site or nodal metastases, obtained during routine clinical care outside of a clinical trial setting, to predict response has also not been examined.

A retrospective review of all surgical patients with non-small cell lung cancer at a single institution imaged between 2000 and 2006 with (18)F-fluorodeoxyglucose positron emission tomography before or after induction therapy was performed.

An increase in standardized uptake value in the primary site of disease during induction therapy was associated with reduced overall survival after resection. Neither pretreatment standardized uptake value nor percentage change in the primary site was associated with overall survival after resection. A decrease in standardized uptake value of greater than 60% in the involved N2 mediastinal nodes was the best predictor of overall survival, better than changes seen in the primary site of disease.

An increase in glucose avidity of non-small cell lung cancers during induction therapy was associated with a worse prognosis compared with stable or any decrease in standardized uptake value. Changes in the glucose avidity of mediastinal nodal metastases may be a stronger predictor of survival than changes in the primary site of disease.