- Patients must have documented ALK positivity at the time of initial crizotinib monotherapy using the Vysis Break-Apart FISH assay (or other Food and Drug Administration [FDA]-approved diagnostic test); samples are deemed to be FISH-positive if greater than or equal to 15% of scored tumor cells had split ALK 5' and 3' probe signals or had isolated 3' signal; FISH status must be documented on the Onstudy Form and a copy of the pathology report from the Vysis Break-Apart FISH assay (or other FDA-approved diagnostic test) must be submitted