Dosimetric evaluation of nanotargeted 188Re-liposome with the MIRDOSE3 and OLINDA/EXM programs

Objective The OLINDA/EXM computer code was created as a replacement for the widely used MIRDOSE3 code for radiation dosimetry in nuclear medicine. A dosimetric analysis with these codes was performed to evaluate nanoliposomes as carriers of radionuclides ( 188 Re-liposomes) in colon carcinoma-bearing mice. Methods Pharmacokinetic data for 188 Re- N , N -bis (2-mercaptoethyl)- N ′, N ′-diethylethylenediamine ( 188 Re-BMEDA) and 188 Re-liposome were obtained for estimation of absorbed doses in normal organs. Radiation dose estimates for normal tissues were calculated using the MIRDOSE3 and OLINDA/EXM programs for a colon carcinoma solid tumor mouse model. Results Mean absorbed doses derived from 188 Re-BMEDA and 188 Re-liposome in normal tissues were generally similar as calculated by MIRDOSE3 and OLINDA/EXM programs. One notable exception to this was red marrow, wherein MIRDOSE3 resulted in higher absorbed doses than OLINDA/EXM (1.53- and 1.60-fold for 188 Re-BMEDA and 188 Re-liposome, respectively). Conclusions MIRDOSE3 and OLINDA have very similar residence times and organ doses. Bone marrow doses were estimated by designating cortical bone rather than bone marrow as a source organ. The bone marrow doses calculated by MIRDOSE3 are higher than those by OLINDA. If the bone marrow is designated as a source organ, the doses estimated by MIRDOSE3 and OLINDA programs will be very similar.