HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH RSS TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JNM Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Shen, S. Articles by DeNardo, G. L. Search for Related Content PubMed PubMed Citation Articles by Shen, S. Articles by DeNardo, G. L.

Planning Time for Peripheral Blood Stem Cell Infusion After High-Dose Targeted Radionuclide Therapy Using Dosimetry

¹ Department of Radiation Oncology, University of Alabama, Birmingham, Alabama
² Department of Internal Medicine, Hematology/Oncology Division, University of California Davis, Sacramento, California
³ Lawrence Livermore National Laboratory, Livermore, California
⁴ Veteran’s Administration Northern California Healthcare System, Mather, California

Myelotoxicity can be ameliorated by peripheral blood stem cell (PBSC) infusion. Continuous irradiation by radioactivity retained in the body after high-dose radioimmunotherapy can damage PBSCs if they are transfused too early. Previously, infusion time was predetermined using the radioactivity concentration in the blood. This study proposes to plan PBSC infusion time based on noninvasive dosimetry that considers damage of PBSCs during PBSC circulation and residence in organs with high radioactivity. Methods: The method considers a time-varying distribution of PBSCs and radioactivity in tissues. Five breast cancer patients received ¹¹¹In-2IT-BAD-m170 for imaging, and 3 of the 5 received high doses of ⁹⁰Y-2IT-BAD-m170 therapy followed by PBSC infusion. ⁹⁰Y concentrations in tissues were extrapolated from quantitative imaging of ¹¹¹In, and ⁹⁰Y blood concentrations were determined from ⁹⁰Y in serial blood samples. The radiation dose to PBSCs was determined by time integration of the organ dose rate and PBSC distribution rate. The radiosensitivity of PBSCs was determined by measuring survival of granulocyte-macrophage colony-forming units with ⁹⁰Y in cell culture. Results: The mean effective half-life of ⁹⁰Y within the imaging period (up to 6 d) was 3.7 d for liver, 2.4 d for spleen, 2.1 d for kidneys, 1.8 d for lungs, and 1.6 d for blood. The survival fractions of PBSCs in patients were determined as functions of the infusion time and the injected dose of ⁹⁰Y-2IT-BAD-m170. To achieve 90% PBSC survival rate for a 2.0-GBq injection dose, PBSC dosimetry suggested a time interval of 13 d after radioimmunotherapy for PBSC infusion. In contrast, the simple blood concentration method suggested an interval about 7 d for the same PBSC survival rate. In our clinical practice, an interval of 2 wk has been used and worked well. Conclusion: A noninvasive dosimetry method was developed for optimizing the time interval for PBSC infusion after high-dose radionuclide therapy. Our studies suggested that the PBSC dosimetry method was more effective than the blood concentration method in determining the optimal time to reinfuse PBSCs for radiopharmaceuticals that have much a higher activity concentration in organs than that in the blood.

Key Words: treatment planning • peripheral blood stem cell • bone marrow • radiation dosimetry • radioimmunotherapy

Related articles in JNM:

THIS MONTH IN JNM

JNM 2005 46: 11a-12a. [Full Text]  

This article has been cited by other articles:

				L. Devizzi, A. Guidetti, C. Tarella, M. Magni, P. Matteucci, E. Seregni, C. Chiesa, E. Bombardieri, M. Di Nicola, C. Carlo-Stella, et al. High-Dose Yttrium-90-Ibritumomab Tiuxetan With Tandem Stem-Cell Reinfusion: An Outpatient Preparative Regimen for Autologous Hematopoietic Cell Transplantation J. Clin. Oncol., November 10, 2008; 26(32): 5175 - 5182. [Abstract] [Full Text] [PDF]