In {HEAD ~ one aspect}, the invention includes a composition for treating a tumor in a subject, comprising liposomes composed of a vesicle forming lipid and between {TAIL ~ about 1 20 mole percent} of a vesicle forming lipid derivatized with a hydrophilic polymer 
In { HEAD ~ one aspect } , the invention includes a composition for treating a tumor in a subject , comprising liposomes composed of a vesicle forming lipid and between { TAIL ~ about 1 20 mole percent } of a vesicle forming lipid derivatized with a hydrophilic polymer
OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH