Comparison of efficacy and safety of different chemotherapy regimens for progressive patients with brain metastasis of small cell lung cancer after radiotherapy

Abstract

Objective To analyze the efficacy and safety of different chemotherapy regimens for treatment of progressive patients with small cell lung cancer (SCLC) brain metastasis after radiotherapy. Methods 96 SCLC brain metastasis patients with progressive intracranial lesions after radiotherapy were divided into four groups: carmustine group (Group A, 28 cases), temozolomide group (Group B, 19 cases), topotecan group (Group C, 24 cases) and no chemotherapy group (Group D, 25 cases). Results In terms of brain metastases, there were no complete response cases in the whole groups. The rates of partial remission (PR), stable disease (SD) and progression of disease (PD) in Group A were 17.8% (5/28), 53.6% (15/28) and 28.6% (8/28), respectively, the response rate (RR) of intracranial lesions was 17.9% (5/28), and disease control (CR+ PR+ SD) rate was 71.4% (20/28). The rates of PR, SD and PD in Group B were 15.8% (3/19), 63.2% (12/19) and 21.1% (4/19), respectively, the RR of intracranial lesions was 15.8% (3/19), and disease control rate was 78.9% (15/19). The rates of PR, SD and PD in Group D were 8.3% (2/24), 54.2% (13/24) and 37.5% (9/24), respectively, the RR rate of intracranial lesions was 8.3% (2/24), and disease control rate was 62.5% (15/24). In Group D, there was no response case, and 20 patients with PD (80.0%) were found. The median progression-free survivals (PFSs) were (3.64±0.43) months, (4.68±0.49) months, (3.58±0.50) months, (2.60±0.31) months in Group A, B, C and D, respectively, and the median overall survivals (OSs) were (18.80±1.74) months, (18.76±1.85) months, (19.10±1.64) months and (9.64±0.84) months, respectively. The median OS of Group A, B or C was longer than that of Group D (P= 0.002). The differences of grade Ⅲ-Ⅳhematologic toxicities among the four subgroups were not statistically different. Patients in Group B had better tolerance to nausea and vomit. In Group D, the central nervous system symptoms such as fatigue and headache occurred frequently. Conclusions The response rate and OS of SCLC brain metastasis patients with progressive intracranial lesions after radiotherapy are improved after chemotherapy, however, PFS is not significantly prolonged. The efficacies of carmustine, temozolomide and topotecan are similar in short and long term, besides, temozolomide shows less adverse events and a higher disease control rate. The application of chemotherapy that could penetrate the blood-brain barrier can improve the efficacy on SCLC brain metastasis patients with progressive intracranial lesions after radiotherapy with well tolerance. Key words: Small cell lung carcinoma; Neoplasm metastases; Drug therapy, combination