Several studies have shown that platelets can sequester tumor RNA by taking up circulating micro-vesicles . These tumor-educated platelets can be isolated and constitute an enriched source of tumor RNA for detection of EML4-ALK rearrangements. A recent study showed that this approach, while being very specific, is more sensitive than those used for plasma RNA . It is noteworthy that the persistence of EML4-ALK rearrangements in platelets of patients treated with crizotinib is associated with tumor progression and poor prognosis . Moreover, the reappearance of this fusion transcript in platelets is a sign of resistance to crizotinib and it occurs several months before progression is detected on radiological examination.