Voxel-based dosimetry predicting treatment response and related toxicity in HCC patients treated with resin-based Y90 radioembolization: a prospective, single-arm study

Eur J Nucl Med Mol Imaging. 2023 May;50(6):1743-1752. doi: 10.1007/s00259-023-06111-9. Epub 2023 Jan 18.

Abstract

Background: There is an increasing body of evidence indicating Y90 dose thresholds for tumor response and treatment-related toxicity. These thresholds are poorly studied in resin Y90, particularly in hepatocellular carcinoma (HCC).

Purpose: To evaluate the efficacy of prospective voxel-based dosimetry for predicting treatment response and adverse events (AEs) in patients with HCC undergoing resin-based Y90 radioembolization.

Materials and methods: This correlative study was based on a prospective single-arm clinical trial (NCT04172714), which evaluated the efficacy of low/scout (555 MBq) activity of resin-based Y90 for treatment planning. Partition model was used with goal of tumor dose (TD) > 200 Gy and non-tumoral liver dose (NTLD) < 70 Gy for non-segmental therapies. Single compartment dose of 200 Gy was used for segmentectomies. Prescribed Y90 activity minus scout activity was administered for therapeutic Y90 followed by Y90-PET/CT. Sureplan® (MIM Software, Cleveland, OH) was used for dosimetry analysis. Treatment response was evaluated at 3 and 6 months. Receiver operating characteristic curve determined TD response threshold for objective response (OR) and complete response (CR) as well as non-tumor liver dose (NTLD) threshold that predicted AEs.

Results: N = 30 patients were treated with 33 tumors (19 segmental and 14 non-segmental). One patient died before the first imaging, and clinical follow-up was excluded from this analysis. Overall, 26 (81%) of the tumors had an OR and 23 (72%) had a CR. A mean TD of 253 Gy predicted an OR with 92% sensitivity and 83% specificity (area under the curve (AUC = 0.929, p < 0.001). A mean TD of 337 Gy predicted a CR with 83% sensitivity and 89% specificity (AUC = 0.845, p < 0.001). A mean NTLD of 81 and 87 Gy predicted grade 3 AEs with 100% sensitivity and 100% specificity in the non-segmental cohort at 3- and 6-month post Y90, respectively.

Conclusion: In patients with HCC undergoing resin-based Y90, there are dose response and dose toxicity thresholds directly affecting outcomes.

Clinical trial number: NCT04172714.

Keywords: HCC; Liver dose toxicity threshold; Resin microspheres; Tumor dose response threshold; Yttrium-90.

Publication types

  • Clinical Trial

MeSH terms

  • Carcinoma, Hepatocellular* / diagnostic imaging
  • Carcinoma, Hepatocellular* / radiotherapy
  • Embolization, Therapeutic* / adverse effects
  • Embolization, Therapeutic* / methods
  • Humans
  • Liver Neoplasms* / diagnostic imaging
  • Liver Neoplasms* / drug therapy
  • Liver Neoplasms* / radiotherapy
  • Microspheres
  • Positron Emission Tomography Computed Tomography
  • Prospective Studies
  • Treatment Outcome
  • Yttrium Radioisotopes / adverse effects

Substances

  • Yttrium Radioisotopes

Associated data

  • ClinicalTrials.gov/NCT04172714