Third-line therapy in the epidermal growth factor receptor mutation-positive advanced nonsmall-cell lung cancer

The treatment of lung cancer is not defined in the third-line setting and remains an unanswered question. Erlotinib is the only drug approved in the third-line setting. With the introduction of effective first- and second-line therapies, more and more patients warrant an effective third-line therapy. We did a post hoc analysis of our randomized trial for the epidermal growth factor receptor (EGFR)-positive patients who received third-line therapy.

The present series is of 85 patients who received third-line therapy. Demographic data were collected which included age, performance status, gender, stage, comorbidities, and sites of metastasis. Data were collected for the type of systemic treatment patients received and number of cycles received. Information related to the impact of treatment on the symptoms of patients and the imaging done for response evaluation was collected.

Of the 85 patients, there were 13 patients (15%) who achieved a partial response and 34 patients (40%) who had stable disease as best response. There were no complete response and 20 patients (24%) had disease progression at the time of first assessment. The median overall survival (OS) was 8.36 months (95% confidence interval [CI] 6.8-9.8 months) and median progression-free survival was 4.4 months (95% CI 3.3-4.9 months). Grade 3 or 4 toxicities were seen in 42.5% (n = 36) of the total patients.

The study provides the patterns and outcomes of systemic treatment in metastatic EGFR-mutated lung adenocarcinoma in patients who have progressed on two or more lines of systemic therapies. This data suggest that third-line systemic therapy may provide meaningful outcomes in these patients.