Evaluating the effectiveness and safety of first-line tyrosine kinase inhibitor with or without radiotherapy for the treatment of patients with oligometastatic EGFR-mutated NSCLC.

This study evaluated the effectiveness and safety of first-line tyrosine kinase inhibitors (TKIs) with or without radiotherapy (RT) for the treatment of patients with oligometastatic (OM) non-small-cell lung cancer (NSCLC) having genetic mutations in the epidermal growth factor receptor (EGFR). The data showed that TKI plus RT was safe and significantly improved overall survival and survival without cancer worsening compared to TKI alone for these patients.

NSCLC is the most common form of lung cancer. NSCLC is responsible for around 85% of all lung cancer diagnoses. Oligometastatic (OM) cancer is cancer that has spread away from the original (primary) organ and has formed a small number of new tumors in one or 2 different organs. Treatments for OM cancer involve systemic (whole-body) treatments such as chemotherapy (CT). However, systemic therapies also increase the risk of side effects on healthy organs and tissues.

Genetic mutations (changes) in EGFR can lead to NSCLC. EGFR TKIs, such as gefitinib (Iressa) and erlotinib (Tarceva), are targeted therapies that block these mutations. This causes cancer cells to stop growing and spreading and are found to be effective in advanced NSCLC. Adding radiotherapy (RT) to systemic therapy has been previously shown to improve survival outcomes in oligometastatic non-small cell lung cancer (NSCLC). However, whether first-line TKIs plus RT are safe and effective for the treatment of patients with OM EGFR-mutant NSCLC is still unclear.

This study involved 133 patients with OM NSCLC who had mutations in the EGFR gene. Patients were divided into 2 groups. Group 1 included 65 patients who received TKI only. Group 2 included 68 patients who received TKIs plus RT. The average follow-up time was 23.6 months.

The average survival without cancer worsening was 12.5 months in group 1 compared to 20.2 months in group 2. After 6 months, 95.2% of the patients in group 1 were alive compared to 99.1% of the patients in group 2. Patients in group 2 were 78% more likely to survive without cancer worsening than patients in group 1.

The average overall survival was 17.6 months in group 1 compared to 25.5 months in group 2. Patients in group 2 were 56% more likely to have a better survival than patients in group 1.

Treatment did not result in severe side effects. The most common side effects in both groups were skin rash. 7.4% of the patients in group 2 experienced inflammation of the lung tissue.

This study concluded that TKIs plus RT was safe and significantly improved overall survival and survival without cancer worsening compared to TKI alone for the treatment of patients with OM EGFR-mutated NSCLC.

The study did not evaluate up-front RT versus RT at the time of cancer progression. RT in this study was not standardized.