TACR1 and cancer: In other words, the surgical procedure increases the release of SP, which, through the NK-1R, could promote after surgery the growth, migration, spreading and metastasis of the remaining local or distant cancer cells (in which the SP/NK-1R system is up-regulated), and as aprepitant blocks these mechanisms, we suggest the blockade of NK-1Rs (before and after the surgical procedure) with the NK-1R antagonist aprepitant to prevent recurrence and metastasis.