Accurate non-tumoral 99mTc-MAA absorbed dose prediction to plan optimized activities in liver radioembolization using resin microspheres. (September 2021)

• Record Type: Journal Article
• Authors: d'Abadie, Philippe; Walrand, Stephan; Hesse, Michel; Amini, Nadia; Lhommel, Renaud; Sawadogo, Kiswendsida; Jamar, François
• Is Part Of: Physica medica. Volume 89(2021)
• Page Start: 250
• Page End: 257
• Publication Date: 2021-09
• Subjects: Radioembolization -- Dosimetry -- Partition model -- 99Tc-MAA SPECT/CT -- 90Y PET/CT; Medical physics -- Periodicals; Biophysics -- Periodicals; Biophysics -- Periodicals; Imagerie médicale -- Périodiques; Radiothérapie -- Périodiques; Rayons X -- Sécurité -- Mesures -- Périodiques; Physique -- Périodiques; Médecine -- Périodiques; 610.153
• DOI: 10.1016/j.ejmp.2021.07.032
• Languages: English
• ISSNs: 1120-1797

Abstract

Highlights: 99m Tc- MAA based dosimetry accurately predicts non-tumoral liver absorbed doses. 99m Tc-MAA based dosimetry predicts with more approximations tumor absorbed doses. Activity planning using the BSA method is suboptimal with frequent underdosing. Activity planning using 99m Tc-MAA imaging optimizes the treatment. Abstract: Aim: The manufacturers' recommended methods to calculate delivered activities in liver radioembolization are simplistic and only slightly personalized. Activity planning could also be based on a 99m Tc-macroaggregated albumin SPECT/CT (MAA) using the partition model but its accuracy is controversial. This study evaluates the dose parameters in the normal liver and in the tumor compartments using MAA SPECT/CT (pre-therapeutic imaging) and 90 Y TOF-PET/CT (post-therapy imaging). Finally, we propose a prescription of the activity as a function of the normal liver MAA distribution. Method: 66 procedures of RE (with resin microspheres) corresponding to 171 lesions were analyzed. Tumor to normal targeted liver uptake (T/NTL), tumor absorbed dose (TD) and whole normal liver absorbed (WNLD) were assessed with MAA and 90 Y imaging. Secondly, activities were recalculated using the MAA distribution in the normal liver compartment to reach the maximal tolerable liver dose. These Activities were compared to activities defined with the BSA method. Results: Compared to 90 Y imaging, our study demonstrated an accurate estimation of the WNLD using MAA imaging (Pearson's R = 0.97, p < 0.001). On the contrary, significant variations were found for TD (R = 0.65, p < 0.001). The MAA T/NTL ratio has a 85% positive predictive value in identifying patients who will get a 90 Y T/NTL ratio above 1.5. Moreover, activities calculated using the MAA distribution in the normal liver compartment were significantly higher to activities defined with the BSA method. Conclusion: Whole normal liver absorbed doses are accurately predicted with MAA imaging and could be used to optimize the activity planning.