Efficacy analysis and multi-factor retrospective study of third-line chemotherapy in 82 Chinese patients with small cell lung cancer

Objective As there is currently no clear recommendation for third-line chemotherapy for small cell lung cancer （SCLC）, its efficacy is unknown. To date, there have rarely been reports of Chinese patients with SCLC who received third-line chemotherapy. Therefore, we investigated the efficacy, safety, and prognostic factors of Chinese patients with SCLC treated with third-line chemotherapy. Methods A retrospective analysis of patients with SCLC who received third-line chemotherapy was performed. Results Between 2007 and 2013, 62 patients [62 men （75.6%）, 20 women （24.4%）; median age at the time of diagnosis, 55 years] received third-line chemotherapy at our center. Of these patients, 44 had limited-stage disease and 38 had extensive-stage disease. On third-line chemotherapy, 55 （67.1%） patients had an Eastern Cooperative Oncology Group performance status （ECOG PS） of 0-1, objective response rate of 15.9%, and median overall survival after third-line chemotherapy （OS-3） and median progres- sion-free survival after third-line chemotherapy （PFS-3） of 5.6 months and 3.0 months, respectively. On univariate analysis, PFS-3 was significantly related with ECOG PS （P = 0.005）, response to second-line chemotherapy （P = 0.002）, response to third-line chemotherapy （P 〈 0.001）, and PFS after second-line chemotherapy （P = 0.026）. OS-3 was significantly related with ECOG PS （P 〈 0.001）, response to third-line chemotherapy （P = 0.033）, PFS after first-line therapy （P = 0.044）, and PFS after second-line therapy （PFS-2） （P = 0.007）. On multivariate analysis, ECOG PS （P = 0.008） and response to third-line chemotherapy （P = 0.046） were independent prognostic factors for PFS-3, while ECOG PS （P = 0.007） and PFS-2 （P 〈 0.001） were independent prognostic factors for OS-3. Conclusion Few patients with SCLC receive third-line chemotherapy. Our findings suggest that patients with an ECOG PS 0-1 and PFS-2 for 〉3 months will be benefit from third-line chemotherapy, which should be actively offered to them.