Metastasis-directed radiotherapy for non-small cell lung cancer failured under TKI: A case report and literature review

Although tyrosine kinase inhibitors (TKI) have revolutionized the treatment of anaplastic lymphoma kinase rearranged non-small cell lung cancer (ALKr-NSCLC), radiotherapy (RT) still plays an essential role for treatment of both intracranial and extracranial metastases, particularly for patients experienced a TKI-failure. We reported the case of a 38-year-old woman with metastatic ALKr-NSCLC who received whole-brain radiotherapy (RT) for multiple brain metastases (BMs), initially. After RT, alectinib was initiated and the patient had a good clinico-radiological response in both intracranial and extracranial regions. However, intracranial progression was developed and, stereotactic radiosurgery (SRS) was applied to the four progressed BMs. Two months after SRS, all BMs disappeared. While patient was using alectinib, a recurrent lung lesion, a hilar lymph node and bone metastasis were detected. Stereotactic body radiotherapy (SBRT) was applied to all metastatic sites and, alectinib was continued again. Three months after SBRT, a complete response was obtained. She has been alive with the initial systemic therapy agent for more than 4 years without evidence of neither disease nor toxicity. SRS/SBRT may eradicate the TKI-resistant tumoral clones and it may prevent switching the systemic therapy, even if there is a failure.