Adenosine triphosphate-based chemotherapy response assay (ATP-CRA)-guided versus empirical chemotherapy in unresectable non-small cell lung cancer

Background: We retrospectively compared adenosine triphosphate-based chemotherapy response assay (ATP-CRA)- guided and empirical chemotherapies for unresectable non- small cell lung cancer (NSCLC) in this case-control study. Patients and Methods: Unresectable NSCLC patients receiving ATP-CRA-guided platinum-based doublets as first-line therapy were enrolled as cases (n=27; 14 platinum-sensitive and 13 platinum-resistant patients). Performance status, stage, and chemotherapeutic regimen-matched patients receiving empirical chemotherapy were selected from the retrospective database as controls (n=93) in a case to control ratio of ~1:3. Results: Response rate and survival (progression-free; overall) in both groups were not significantly different. However, the platinum- sensitive subgroup by ATP-CRA showed a higher response rate than the empirical group (71 versus 38% ; p=0.023) with a trend toward longer progression-free survival (8.7 versus 4.8 months for platinum-sensitive versus empirical; p=0.223) and overall survival (not reached versus 12.6 months for platinum- sensitive versus empirical for p=0.134). Conclusion: ATP-CRA may be helpful in selecting platinum-responsive patients in unresectable NSCLC. We consider that nonplatinum doublets in platinum-resistant patients by ATP-CRA may be a more adapted approach than platinum-based doublets in future clinical trials. Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death around the world (1). Most patients with NSCLC eventually succumb to distant metastasis. Despite advances in palliative chemotherapy, however, the prognosis of advanced NSCLC is still very poor. To overcome this limitation, attention is turning to developing of techniques that could provide predictive information regarding a particular tumors chemosensitivity, as a means of enhancing patient selection for a specific chemotherapy option. This is based on the concept developed 30 years ago of selecting chemotherapeutic agents for an individual patient by in vitro drug sensitivity testing (2).