Erlotinib versus pemetrexed for pretreated non-squamous non-small cell lung cancer patients in clinical practice.

BACKGROUND/AIM: Erlotinib and chemotherapy have shown similar efficacy for pretreated non-small cell lung cancer (NSCLC) patients, but none of the large studies have selected patients based on histology. We present a retrospective single-center series of advanced non-squamous NSCLC patients treated with erlotinib or pemetrexed as second-line therapy. Our aim was to compare the efficacy and safety data under clinical practice conditions and to identify subgroups of patients who could benefit more from these therapies.

METHODS: A total of 88 patients were included. Squamous histology was our main exclusion criterion. EGFR mutation status was known for 54.5% of the patients; 6 patients treated with erlotinib and 2 with pemetrexed had EGFR-mutated tumors. Smoking history was analyzed as possible predictive factor of efficacy.

RESULTS: No significant differences in progression-free survival (PFS; 3 vs. 2.5 months, p = 0.06) or overall survival (OS; 4.9 vs. 7.4 months, p = 0.733) between the erlotinib and pemetrexed groups were found in the overall population. EGFR wild-type patients had a similar median PFS with erlotinib compared to pemetrexed (2.7 vs. 2.3 months, p = 0.42), with no statistical differences in OS. Statistically significant differences in OS in favor of pemetrexed for current smokers (3 vs. 7.1 months, p = 0.017) were found, while erlotinib achieved significantly better PFS in never-smokers compared to former smokers (3.5 vs. 2.7 months, p = 0.005). Serious adverse events were uncommon but more frequent with pemetrexed, and were mainly related to hematologic toxicity.

CONCLUSIONS: Erlotinib should be considered as another equal option in second-line treatment for EGFR wild-type patients as well as for subpopulations with unknown mutational status. Smoking history could be a useful clinical marker to choose a second-line treatment.