ALK, squamous cell carcinoma, brain metastases, crizotinib
Anaplastic lymphoma kinase (ALK) gene-rearrangement in non-small-cell lung cancer (NSCLC) was first reported in 2007 (1). EML4-ALK oncogene fusion is the most common form and has been identified in 2-5% patients with NSCLC, especially adenocarcinoma (2-5). It has defined a molecular subgroup of NSCLC that is susceptible to targeted kinase inhibition. Crizotinib, a specific ALK inhibitor, has shown marked clinical response to ALK rearranged NSCLC (6, 7), but it has been reported its poor blood brain barrier penetration (8). How about the efficacy and safety of crizotinib in NSCLC with brain metastases? How to treat brain metastasis patients with ALK sensitive mutation? What could be the best therapeutic strategy, ALK inhibitor, radiotherapy, chemotherapy or combination? This case shows that second line of crizotinib is effective against advanced squamous cell carcinoma (SCC) with brain metastases carrying EML4-ALK oncogene fusion.