Composition comprises a cyanobacterium, an anticancer agent, and selenium. An independent claim is included for obtaining the composition, comprising mixing the cyanobacteria with selenium based compound, and adding the anticancer agent to the resulting mixture. ACTIVITY : Cytostatic. MECHANISM OF ACTION : None given.Linvention a pour objet une composition comprenant une micro-algue séléniée et un agent actif, notamment anti-tumoral, comme médicament à usage humain, notamment pour le traitement du cancer.