¹⁶⁹Yb-cisdichlordimethionine platinum is an oncophilic radiopharmaceutical, particularly useful in staging and monitoring the therapy of malignant lymphomas.
Our previous paper in this journal on kinetics of whole body and organ retention of ¹⁶⁹Yb-PtCl₂Meth₂ and on effective dose for man, presented the details of the kinetics of retention and excretion of the examined compound in rat and in man. Now, additional measurements of whole body and organ retention in rats, which were intravenously injected with ¹⁶⁹Yb-Cl₃ has been carried out.
The results obtained in the study indicate that the effective whole body retention of ¹⁶⁹Yb is declining faster when administered in the chemical form of ¹⁶⁸Yb-PtCl₂Meth₂ complex than after administration of simple compound, like ¹⁶⁹Yb-Cl₃. The ¹⁶⁹Yb radiopharmaceutical is retained to a much less degree in skeleton, muscles, liver and spleen, which makes the tumour/background ratio in scintigraphic images much higher. It seems that these specific characteristics of ¹⁶⁹Yb-PtCl₂Meth₂ complex, regarding kinetics of whole body and organ retention, differentiating it from a simple compounds of ¹⁶⁹Yb, are highly beneficial for patients.