Effectiveness of crizotinib in a patient with ALK IHC-positive/FISH-negative metastatic lung adenocarcinoma

We report a case of crizotinib effectiveness in a heavily pretreated patient with a metastatic NSCLC initially considered IHC-positive and FISH-negative for ALK rearrangement. After repeated analyses of tumor samples, borderline ALK FISH-positivity (18.5% positive cells) was demonstrated.