Room: Exhibit Hall | Forum 5
Purpose: Transarterial radioembolization (TARE) using yttrium-90 (Y90) microspheres is an effective treatment for hepatocellular carcinoma (HCC). Current imaging assessment occurs one to two months post-treatment to determine effectiveness due to radical tissue changes in response to radiation. This delay may negatively affect patient outcomes, motivating identification of earlier biomarkers for treatment outcome. Prior to receiving TARE, all patients at UMMC undergo 99mTc-macroaggregated albumin single-photon emission computerized tomography (99mTc-MAA SPECT). Our goal in this work was to use multimodal imaging to assess radiation delivery and patient outcomes. Specifically, we investigated the relationship between dose volume histograms (DVH) and dosimetric maps generated from the 99mTc-MAA SPECT/CT/MRI scans and treatment outcomes.
Methods: Nine patients who received TARE with Y90 as their first treatment of HCC were retrospectively analyzed. Radiation dosage maps and DVH using pre-treatment 99mTc-MAA SPECT/CT/MRI data and post-treatment CT and MRI were generated. Patients were stratified into 3 categories (3 Complete Response, 5 Partial Response, 1 Progressive Disease) based on treatment response as determined by modified Response Evaluation Criteria in Solid Tumors (mRECIST).
Results: Area under the curve (AUC) values were generated and used to quantify information from the DVH. TAUC values were then compared with treatment response as determined by mRECIST.
Conclusion: Analysis of dosage distribution maps calculated from 99mTc-MAA SPECT/CT/MRI may enable us to optimize dose delivery methods and prove useful as a planning tool to predict tumor response to TARE. However, data obtained from the 99mTc-MAA SPECT/CT scans of nine patients who underwent TARE do not show any obvious relationship with their treatment responses as determined by mRECIST.