Objective  To investigate the efficacy and safety of bevacizumab combined with chemotherapy in patients with retreated advanced non-squamous non-small cell lung cancer (NSNSCLC) and analyze its prognostic factors.

  Methods  Forty-one patients with previously treated advanced NSNSCLC in Beijing Chest Hospital from February 2013 to June 2017 were recruited. Clinical data of the patients were retrospectively analyzed. There were 38 cases of adenocarcinoma and 3 cases of other pathological types. Bevacizumab combined with chemotherapy served as second-line treatment for 19 patients, and it served as beyond second-line therapy for 22 patients. Eighteen patients harbored epidermal growth factor receptor (EGFR) gene mutations, while the other 23 patients harbored wild-type EGFR gene. The efficacy and safety of bevacizumab combined with chemotherapy were evaluated. To evaluate the prognostic factors, single and multiple factor analyses were conducted.

  Results  All patients received bevacizumab combined with chemotherapy and could be evaluated for response. The mean number of cycles of chemotherapy and chemotherapy combined with bevacizumab were 3.1 and 5.0, respectively. The objective response rate (ORR) of all recruited patients was 12.2%. The disease control rate (DCR) was 82.9%. Regarding the effect of second-line and beyond second-line therapy in patients, data were similar. The ORRs were 10.5% and 13.6%, respectively (P=0.572), and DCRs were 89.5% and 77.3%, respectively, without significantly statistical difference (P=0.271). The median progression-free survival (PFS) and overall survival (OS) were 4.6 months 95% confidence interval (CI) 3.619-5.581 and 11.9 months (95% CI 9.797-14.003), respectively. In the single factor analysis, patients with EGFR mutations, those who received > 4 cycles of bevacizumab administration, and women had longer OS (χ²=19.673, P=0.000; χ²=6.820, P=0.009; and χ²=6.374, P=0.012; respectively). The Cox regression analysis showed that EGFR mutation status and number of cycles of bevacizumab administration were independent prognostic factors hazard ratio (HR)=0.129, P=0.001 and HR=0.336, P=0.012; respectively. The common adverse reactions include bone marrow suppression, bleeding, hypertension, and proteinuria. Most of them were grade 1-2.

  Conclusions  Bevacizumab combined with chemotherapy provides good efficacy and controllable safety in patients with retreated advanced NSNSCLC. Patients with EGFR mutations and > 4 cycles of bevacizumab administration have superior prognosis.