Background: The interest of first- and second-line treatments in non-small cell lung cancer (NSCLC) has been demonstrated by successive randomized trials. Improvements in lung cancer care have routinely allowed a significant proportion of patients to be considered for third-line treatment.
Methods: A retrospective analysis was performed, including all consecutive patients with advanced NSCLC, who received at least three lines of systemic antineoplastic treatment at our institution.
Results: From a population of 613 patients treated with first-line treatment, a total of 173 patients received third-line treatment (cytotoxic chemotherapy in 131 patients; epidermal growth factor (EGFR) tyrosine kinase inhibitors in 42 patients). Only 13 patients (8%) received less than 75% of the theoretical dose intensity; 22 patients (13%) presented with severe toxicities. Symptom relief and performance status (PS) improvement were observed in 121 (92% of the 131 patients with symptoms) and 90 patients (52%), respectively. Using multivariate analysis, survival after third-line treatment was significantly increased in patients younger than 70 years-old (hazard ratio [HR] = 0.73, 95% confidence interval [CI]: 0.53-0.99, p = 0.047), who smoked less than 10 pack-years (HR = 0.82, 95% CI: 0.57-0.93, p = 0.036), with no cancer-related symptoms (HR = 0.75, 95% CI: 0.61-0.92, p = 0.007), a weight loss inferior to 5 kg since the beginning of second-line (HR = 0.63, 95% CI: 0.52-0.75, p = 0.013), a PS 0 to 1 (HR = 0.81, 95% CI: 0.76-0.86, p = 0.008), and no extrathoracic tumor spread at initiation of third-line treatment (HR = 0.67, 95% CI: 0.47-0.94, p = 0.042). Disease control after both first- and second-line treatments was the strongest predictor of prolonged survival after third-line treatment (HR = 0.47, 95% CI: 0.33-0.67, p = 0.001).
Conclusions: Patients with advanced NSCLC may benefit from third-line treatment. The best candidates can be identified using standard prognostic factors, such as PS, and disease control after first- and second-line treatments.