13th Annual Global Embolization Symposium & Technologies
Purpose : The goal of this randomized multicentric study was to evaluate tumor absorbed dose (TD) and response rate (RR) of the index lesion after 90Y loaded glass microsphere SIRT in HCC patients using a standard or a personalized dosimetric approach.
Material and Methods : 56 HCC patients with at least one lesion larger than 7cm (index lesion) were included and treated by SIRT. Treatment arm was randomly assigned (1:1). In the standard dosimetric arm (SDA) the goal was to deliver 120±20Gy to the treated volume. In the personalized dosimetric arm (PDA) the goal was to deliver at least 205Gy to the index lesion, intensification with a dose >150Gy to the treated volume was allowed but without exceeding 120Gy to the healthy treated liver. Dosimetry was based on MAA SPECT/CT. Response of the index lesion was evaluated at 3 month using EASL criteria.
Results : RR was significantly increased in the PDA versus the SDA, respectively 71.4% and 35.7%, p=0.007. Mean tumor dose (MTD) was significantly higher in the PDA versus the SDA, respectively 324±131Gy and 221±110Gy, p=0.01. MTD was significantly higher for responding lesions vs non responding ones, respectively 329±145Gy and 225±110Gy, p<10-3. RR was significantly higher for TD >205Gy vs TD<205, respectively 73.3% and 36.8%, p=0.011. Two early deaths (occurring within 3m from SIRT) were reported in the SDA and none in the PDA.
Conclusions : MAA SPECT/CT based personalized dosimetry with intensification is safe and significantly highly increases the response rate of large HCC. MAA SPECT/CT based personalized dosimetry has to be used in new RCT trial evaluating SIRT efficacy.