Smoking history as a predictive factor of treatment response in advanced non-small-cell lung cancer: a systematic review

Recent trials in patients with advanced non-small-cell lung cancer (NSCLC) suggest that nonsmokers may benefit more from epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapy than will smokers. The aim of this systematic review was to assess smoking history as a predictive factor for treatment outcomes in patients with NSCLC. Relevant published literature was identified through systematic searches of databases (MEDLINE, EMBASE, Cochrane Library), oncology and thoracic journals, and abstracts from major oncology conferences using prespecified criteria. Articles reporting treatment outcomes (overall survival [OS], progression-free survival [PFS], and/or response rate) in smoking history subgroups from randomized controlled trials of targeted therapy and/or chemotherapy were reviewed. Data from 30 trials (32 articles, 4 abstracts) were included. Of these, 23 trials tested first-line therapy. Treatment arms included EGFR TKIs (13 trials), EGFR monoclonal antibodies (2 trials), non-EGFR targeted treatments (9 trials), chemotherapy (27 trials), and placebo or best supportive care only (3 trials). Smoking history definitions and analyses of its effect on treatment outcomes varied widely. Only 11 trials reported testing for a treatment-by-smoking history interaction. The available evidence supports but does not confirm smoking history as a predictive factor for the response to TKIs, particularly in previously treated patients. The evidence does not support smoking history as a predictor of response to non-EGFR-targeted therapies or chemotherapy. Smoking history and its effect on treatment response are inadequately reported. More rigorous collection, analysis, and reporting may clarify whether smoking history is a predictor of treatment response in advanced NSCLC.

Gemcitabine administered as a short infusion versus a fixed dose rate in combination with cisplatin for the treatment of patients with advanced non-small cell lung cancer

Previous studies have indicated that, in combination with cisplatin, fixed dose rate gemcitabine may be more efficacious than standard infusion gemcitabine. This open-label, randomised phase II study was aimed to compare the efficacy and safety of these regimens as treatment for advanced non-small cell lung cancer (NSCLC) in Latin American patients. Sixty-four patients were randomised to receive up to six cycles of treatment with cisplatin 75 mg/m(2) on Day 1 plus either gemcitabine 1000 mg/m(2) over 30 min on Days 1 and 8 of a 21-day cycle (standard arm, N=33) or gemcitabine 1000 mg/m(2) at a fixed dose rate of 10 mg/m(2)/min on Days 1 and 8 of a 21-day cycle (FDR arm, N=31). In the standard arm, 9 of 33 (27%) patients responded compared with 6 of 30 (20%) patients in the FDR arm (odds ratio: 0.67, 95% CI, 0.21-2.2; p=0.56). Median overall survival was 7.5 months in the standard arm and 9.9 months in the FDR arm. One-year survival rates were 35% and 37% in the standard arm and the FDR arm, respectively. Patients in the FDR arm experienced more grade 3/4 haematological toxicity than those in the standard arm (48% versus 21%). The results of this trial do not support FDR administration of gemcitabine in preference to the standard administration in Latin American patients with NSCLC.

Erlotinib in previously treated non-small-cell lung cancer

BACKGROUND

We conducted a randomized, placebo-controlled, double-blind trial to determine whether the epidermal growth factor receptor inhibitor erlotinib prolongs survival in non-small-cell lung cancer after the failure of first-line or second-line chemotherapy.

METHODS

Patients with stage IIIB or IV non-small-cell lung cancer, with performance status from 0 to 3, were eligible if they had received one or two prior chemotherapy regimens. The patients were stratified according to center, performance status, response to prior chemotherapy, number of prior regimens, and prior platinum-based therapy and were randomly assigned in a 2:1 ratio to receive oral erlotinib, at a dose of 150 mg daily, or placebo.

RESULTS

The median age of the 731 patients who underwent randomization was 61.4 years; 49 percent had received two prior chemotherapy regimens, and 93 percent had received platinum-based chemotherapy. The response rate was 8.9 percent in the erlotinib group and less than 1 percent in the placebo group (P<0.001); the median duration of the response was 7.9 months and 3.7 months, respectively. Progression-free survival was 2.2 months and 1.8 months, respectively (hazard ratio, 0.61, adjusted for stratification categories; P<0.001). Overall survival was 6.7 months and 4.7 months, respectively (hazard ratio, 0.70; P<0.001), in favor of erlotinib. Five percent of patients discontinued erlotinib because of toxic effects.

CONCLUSIONS

Erlotinib can prolong survival in patients with non-small-cell lung cancer after first-line or second-line chemotherapy.