Methods and devices for improved targeting to a site in an organism, particularly to a tumor target site and for extracorporeal affinity adsorption, particularly in the treatment of cancer, atherosclerosis, including coronary artery disease, unstable angina, other acute ischemic syndromes and idiopathic dilated cardiac myopathy. In one aspect of the invention, a combination is provided comprising an extracorporeal device (1) having contained therein a binding compound (11) bound to a carrier (9), the binding compound having affinity for a binding partner, and a plurality of affinity binders (15), each of said affinity binders comprising a first portion (19) comprising the binding partner and a second portion (17) adapted to bind selectively with a species, the second portions of each of said affinity binders differing from each other.