Use of medium molecular weight polymer contrast media to differentiate benign and malignant tumors using modern imaging techniques

摘要

It has been found surprisingly that by using metal complex-conjugates with a polymeric basic structure and a mean molecular weight of between 10,000 and 40,000 dalton, it is possible to otbtain excellent differentiation between malignant and benign tumours in areas of the body without a blood-brain barrier. Contrast agents of this type not only permit reliable differentiation between malignant and benign tumours, they are also characterised by the fact that they can be completely eliminated from the body and thus have good tolerability. Suitable metal complex-conjugates with a polymeric basic structure and a means molecular weight in the range indicated above are disclosed in the German patent applications DE 39 38 992 and DE 195 25 924, as well as in the US patents US 5,338,532; 4,507,466; 4,631,337; 4,587,329; 4,568,737 and 4,507,466. Such polymeric basic structures are referred to as cascades or dendrimers, and contrast agents containing conjugates of these polymers with metal complexes can be referred to as cascade or dendrimeric contrast agents. Preference is given in particular to metal complex-conjugates carrying between 24 and 36 paramagnetic metal complexes, in particular metal complexes of gadolinium, at the end-position groups of the polymeric basic structure.