Effects of Afatinib on the Treatment and Prognosis of Brain Metastasis in Advanced EGFR Mutation (+) NSCLC

Abstract

Introduction Afatinib has shown encouraging results in EGFR mutation (+) patients. According to LUX-Lung trials, afatinib is known to be effective in delaying the occurrence of brain metastases, and it is also known to be effective in treating patients with brain metastases by penetrating the blood-brain barrier. We conducted a study on the effect on brain metastasis in EGFR M(+) patients who received afatinib as the 1st line from the KATRD EGFR cohort data.

Methods We retrospectively reviewed data from 422 patients who started afatinib therapy among patients enrolled in the KATRD EGFR cohort between April 2007 and August 2021. A total of 15 sites participated in patient registration.

Results The mean age was 64 (SD, 10.9). The progression free survival and overall survival (OS) of the KATRD afatinib cohort were 20.2 and 48.6 months, respectively. Compared to those with brain metastases, afatinib significantly prolonged overall survival in patients without brain metastases (65.6 vs. 32.2 months, P < 0.001). The best overall responses for all patients and those with brain metastasis were 65.3% and 64%, respectively. At the time of diagnosis of lung cancer, 34% (145/422) of patients had brain metastasis, of which 14% (60/422) were treated only with afatinib, and the remaining patients were treated with surgery, gamma knife, CyberKnife, whole brain radiation therapy or stereotactic radiosurgery. Especially, there was no difference in survival between the two groups in patients treated with afatinib alone compared with those who received radiotherapy or surgery (32.7 vs. 30.3 months, P=0.77).

Conclusions The OS of the cohort was promising, especially in patients without brain metastasis. Further studies are needed to determine whether afatinib monotherapy or afatinib treatment after surgery or radiotherapy is more appropriate in patients with brain metastases when diagnosed with lung cancer.