DNA repair capacity correlates with standardized uptake values from 18 F-fluorodeoxyglucose positron emission tomography/CT in patients with advanced non-small-cell lung cancer.

Objective: The DNA repair capacity (DRC) of tumor cells is an important contributor to resistance to radiation and platinum-based drugs. Because DRC may be affected by tumor cell metabolism, we measured DRC in lymphocytes from patients with non-small-cell lung cancer (NSCLC) and compared the findings with the maximum standardized uptake value (SUVmax ) on18 F-fluorodeoxyglucose positron emission tomography (FDG PET) after (chemo)radiation therapy.

Methods: This study included 151 patients with stage IA-IV NSCLC who had FDG PET at a single institution and donated blood samples before chemotherapy. We assessed the correlation of DRC, measured in peripheral T lymphocytes by a host-cell reactivation assay with SUVmax and their associations with overall survival (OS) time by hazards ratios calculated with a Cox proportional hazards regression model.

Results: SUVmax of the primary tumor at diagnosis was inversely associated with lymphocyte DRC ( r  = -0.175, P  = 0.032), particularly among patients with advanced disease ( r  = -0.218, P  = 0.015). However, ΔSUVmax of primary tumor was not significantly associated with DRC ( r  = 0.005, P  = 0.968). SUVmax of regional lymph nodes at diagnosis ( r  = -0.307, P  = 0.0008) and after (chemo)radiation treatment ( r  = -0.329, P  = 0.034) and SUVmax of the primary tumor after (chemo)radiation treatment ( r  = -0.253, P  = 0.045) were also inversely associated with OS time.

Conclusion: DRC was inversely associated with primary tumor SUVmax before treatment but not with ΔSUVmax after (chemo)radiation.