The first- or second-line use of pemetrexed sequentially with EGFR-TKI did not differ in PFS for advanced NSCLC patients harboring EGFR-mutant tumors.

Abstract

e20531 Background: Both EGFR-TKI and pemetrexed doublet chemotherapy (P) are two effective therapies in advanced NSCLC patients with EGFR mutant tumors. But which one should be used in first-line remains controversial. Methods: This was a retrospective study where patients prescribed with EGFR-TKI (gefitinib or icotinib) from Jan 2013 to Jan 2016 were screened. Patients must have metastastic diseases harboring TKI-sensitizing EGFR mutation. They must be older than 18 years, and have evaluable target lesions. Whether TKI or P was used in the first line, it must be switched to the other in the second line. PFS in both first line (PFS1) and second line (PFS2) was collected. Results: We screened totally 550 patients (gefitinib n = 455, icotinib n = 95) to enroll a cohort of 36 patients. They were all adenocarcinoma except 1 adenosquamous carcinoma. Gender (M or F), PS (0 or 1), mutation type (Exon19Ddel or other) were equally distributed. The median age was 50.5 years. For the whole cohort, the total PFS (PFS1+PFS2) was 18.1 m (95%CI: 15.2-21.1 m). For those (n = 24) receiving first-line TKI, PFS1, PFS2, and total PFS were 10.3 m, 6.6 m, and 19.2 m. And for those receiving first-line P (n = 12), they were were 3.4 m, 11.5 m, and 16.5m. The total PFS in both groups did not differ significantly (p = 0.548). Conclusions: Our results argued the sequential usage of TKI and P achieve a comparable PFS irrespective of the sequence.