Skip to main content
Internal view of patient's torso demonstrating targeted accuracy of TheraSphere Y-90 Glass Microspheres in liver.

TheraSphere™ Y-90 Glass Microspheres

Ochsner tumor dose analysis

Ochsner study overview

Retrospective, single-center analysis of solitary HCC patients (n=56) treated with TheraSphere Y-90 Glass Microspheres.

Filename
Ochsner_Tumor_Dose_Analysis_datasheet_PI-1900506-AA.pdf
Size
771 KB
Format
application/pdf
Download Ochsner tumor dose analysis
See full manuscript

New TheraSphere analysis: Durable, reproducible outcomes demonstrated with high dose and high radiation per microsphere (RPM). 1

Single-center data builds on previously published radiation segmentectomy studies (LEGACY2 and RASER3) to demonstrate consistent outcomes with late first week/early second week dosing.

Sandow T, Gimenez J, Nunez K, Tramel R, Gilbert P, Oliver B, Cline M, Fowers K, Cohen A, Thevenot P, Using Voxel-based Dosimetry to evaluate sphere concentration and tumor dose in Hepatocellular Carcinoma treated with Y-90 Radiation Segmentectomy with glass microspheres, Journal of Vascular and Interventional Radiology (2024), doi: https://doi.org/10.1016/j.jvir.2024.05.020.

Study objective

Explore the relationship between microsphere deposition and distribution and various outcomes following radiation segmentectomy; validate current literature regarding efficacy, pathologic outcomes and adverse events.

Analysis design / methods

Post-treatment voxel-based dosimetry was evaluated using Simplicit90Y™ software and utilized to calculate sphere concentration to tumor. Time to progression (TTP), treatment response, pathologic response, and adverse events were studied.

""

Results

Strong radiologic and pathologic outcomes achieved in radiation segmentectomy with ablative dosing and high radiation per microsphere

474 Gy (177–1,290) Median targeted dose to perfused volume, 732 Gy (252–1,776) Median Tumor Absorbed Dose, 1,446 Bq Week 1 Thursday (217-2,621) Median RPM and Treatment Day.

Duration of Response and Response Rates in line with LEGACY2 and RASER3 TheraSphere Radiation Segmentectomy Data

97% durable response at 2 years.
97% durable response at 2 years.
As perfused volumes decreased, both tumor and normal tissue sphere concentration increased.
83% of patients had a tumor sphere concentration <20,000 spheres/mL.

Despite tumor heterogeneity, high RPM (Week 2 Tuesday or earlier) can achieve:

  • Reproducible high rates of complete radiologic response
  • Durable tumor control
  • Pathologic necrosis

Adverse events

Ablative radiation segmentectomy with high radiation per microsphere is well-tolerated with limited AEs in patients with preserved liver function.

0 grade less than or equal to 3 AEs at 60 day follow up; 2 grade less than or equal to 3 AEs at 180 day follow up.

Patient characteristics

All patients in this analysis received radiation segmentectomies.

Patient demographics and baseline characteristics

Ochsner study patient demographics and patient characteristics.

Abbreviations: 90Yittrium (90Y), hepatocellular carcinoma (HCC), interquartile range (IQR), hepatitis C virus (HCV), alcoholic liver

Conclusion

Ablative dosing for radiation segmentectomy with high RPM yields durable radiologic and pathologic outcomes with limited adverse events. The study further supports contemporary radiation segmentectomy techniques by targeting doses greater than 400 Gy to the perfused volume and treating within recommended treatment days (Week 1 Wednesday – Week 2 Tuesday). This approach optimizes radiation per microsphere and allows more critical hits in the “coldest” areas of the tumor, maximizing tumor dose coverage.

Analysis further supports results from previously published landmark trials by following Dosimetry Steering Committee Guidelines

Dosimetry Steering Committee recommended treatment days.

Patient/tumor characteristics and Outcomes

patient and tumor characteristics, and outcomes from Legacy, Raser, Ochsner studies.

References

  1. Radiation per microsphere (RPM) is a number that refers to the specific activity (SA) of a microsphere (Bq/Sphere).
  2. Salem R, Johnson GE, Kim E, Riaz A, Bishay V, Boucher E, Fowers K, Lewandowski R, Padia SA. Yttrium-90 Radioembolization for the Treatment of Solitary, Unresectable Hepatocellular Carcinoma: The LEGACY Study. Hepatology. 2021 Mar 19. doi: 10.1002/hep.31819.
  3. Kim E, Sher A, Abboud G, et al. Radiation segmentectomy for curative intent of unresectable very early to early stage hepatocellular carcinoma (RASER): a single-centre, single-arm study [published online ahead of print, 2022 May 23]. Lancet Gastroenterol Hepatol. 2022;S2468-1253(22)00091-7. doi:10.1016/S2468-1253(22)00091-7
  4. Radiation per microsphere (RPM) is a number that refers to the specific activity (SA) of a microsphere (Bq/Sphere). The RPM for TheraSphere is calculated based on targeted values and process means. Actual RPM can vary between microspheres. All numbers as of Noon Eastern Time. Ref Technical Report 97124387.
  5. Sandow T, Gimenez J, Nunez K, Tramel R, Gilbert P, Oliver B, Cline M, Fowers K, Cohen A, Thevenot P, Using Voxel-based Dosimetry to evaluate sphere concentration and tumor dose in Hepatocellular Carcinoma treated with Y-90 Radiation Segmentectomy with glass microspheres, Journal of Vascular and Interventional Radiology (2024), doi: https://doi.org/10.1016/j.jvir.2024.05.020.
  6. TheraSphere™ Y-90 Glass Microspheres RASER Study. Data on file.
  7. TheraSphere™ Y-90 Glass Microspheres LEGACY Study. Data on file.
  8. Salem, R., Padia, S.A., Lam, M. et al. Clinical, dosimetric, and reporting considerations for Y-90 glass microspheres in hepatocellular carcinoma: updated 2022 recommendations from an international multidisciplinary working group. Eur J Nucl Med Mol Imaging 50, 328 -343 (2023). https://doi.org/10.1007/s00259-022-05956-w

Boston Scientific is not responsible for the collection, analysis or reporting of the investigator-sponsored research output which is the sole responsibility of the investigators. Boston Scientific’s involvement in investigator-sponsored research is limited to providing financial support for research that advances medical and scientific knowledge about our products. Indications, contraindications, warnings and instructions for use can be found in the product labeling supplied with each device.

TheraSphere is a registered trademark of Theragenics Corporation used under license by Boston Scientific Medical Device Limited, a wholly owned indirect subsidiary of Boston Scientific Corporation.