The vast intratumoral and intertumoral heterogeneity and dynamic changes in an ALK tumor temporally, particularly at each drug relapse, suggest that treatment approaches to manage these tumors in an individual seek also to use a personalized tumor approach moving away from the ‘one size fits all’ empirical practice of switching from drug A to drug B with diminishing benefit from each sequential therapy, as is largely practiced in the clinic to date. Here, ALK is linked to neoplasm.