High response of second-line chemotherapy with pemetrexed or gemcitabine combined with carboplatin in patients with non-small-cell lung cancer experiencing progression following 6 months after concluding platinum-based chemotherapy.

Because of improved therapeutic results after first-line platinum-based chemotherapy in patients with stage IV non-small-cell lung cancer (NSCLC), second-line chemotherapy may be considered for a growing number of patients. Approximately, 10% of patients have an interval time after concluding first-line platinum-based chemotherapy greater than 6 months. These patients may achieve high tumor responses when platinum is again used in second-line treatment. Twenty-three patients experiencing progression following 6 months after concluding platinum-based chemotherapy were managed with second-line treatment with carboplatin combined with gemcitabine or pemetrexed. Overall response, progression-free survival (PFS), and overall survival (OS) after initiation of second-line treatment were calculated for all patients. Median PFS after first-line treatment was 12.6 months (95% confidence interval [95% CI], 10.4-14.7 months). Partial response was achieved in 7 of 23 patients, resulting in an overall response of 30.4% (95% CI, 11.6-49.0). Following initiation of second-line chemotherapy, median PFS was 5.9 months (95% CI, 1-10.9 months) and median OS was 12.5 months (95% CI, 3.5-21.5 months). The 1-year survival rate for all patients was 61.0% (95% CI, 29.5-82.0). Adding these results to those of the 10 previously published trials, 75 of 326 patients, 23%, (95% CI, 18.7-27.3) presented an overall response with the use of second-line platinum-based chemotherapy. The use of platinum combinations as second-line chemotherapy seems to have a place in the management of patients with advanced NSCLC, especially those with an interval time to progression greater than 6 months.