Morgensztern D, et al. - Given that a wide range of changes in tumor size is included in a partial response according to the Response Evaluation Criteria in Solid Tumors, researchers investigated if further specification of tumor reduction based on the depth of response (DpR) would offer a more accurate relation to outcomes for patients who received first-line platinum-based chemotherapy for non–small cell lung cancer (NSCLC). They carried out a retrospective analysis of NSCLC patients who received carboplatin in combination with nab-paclitaxel or solvent-based paclitaxel. Based on the maximum tumor reduction from the baseline, four quartiles were defined: quartile 1 [Q1], >0% to 25%; quartile 2 [Q2], >25% to 50%; quartile 3 [Q3], >50% to 75%; and quartile 4 [Q4], >75%. These quartiles were compared with those patients with no tumor reduction (NTR). The patients in the NTR, Q1, Q2, Q3, and Q4 groups were found to have median overall survival (OS) values of 4.8, 10.4, 14.5, 19.3, and 23.5 months, respectively. Findings revealed a strong association of DpR with OS in patients with NSCLC taking first-line platinum-based therapy.