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Time dependence of the activity concentration ratio of red marrow to blood and implications for red marrow dosimetry.

Hindorf, Cecilia LU ; Lindén, Ola LU ; Tennvall, Jan LU ; Wingårdh, Karin LU and Strand, Sven-Erik LU (2002) In Cancer 94(4 Suppl). p.1235-1239
Abstract
BACKGROUND: The method for red marrow dosimetry in radioimmunotherapy, in the absence of specific activity uptake in red marrow, is based on the activity measured in the blood or plasma. The activity concentration ratio of red marrow to blood is then assumed to be constant. The aim of the current study was to determine whether this ratio varies with time after injection. METHODS: Measurements were carried out with both animals and patients.Tumor-bearing rats were intravenously injected with iodine-131-, iodine-125-, indium-111-, or rhenium-188-labeled BR96, a chimeric immunoglobulin G1 monoclonal antibody. (All were chelate-labeled, except for iodine-131, which was iodogen-labeled.) Measurements were made of the activity concentration in... (More)
BACKGROUND: The method for red marrow dosimetry in radioimmunotherapy, in the absence of specific activity uptake in red marrow, is based on the activity measured in the blood or plasma. The activity concentration ratio of red marrow to blood is then assumed to be constant. The aim of the current study was to determine whether this ratio varies with time after injection. METHODS: Measurements were carried out with both animals and patients.Tumor-bearing rats were intravenously injected with iodine-131-, iodine-125-, indium-111-, or rhenium-188-labeled BR96, a chimeric immunoglobulin G1 monoclonal antibody. (All were chelate-labeled, except for iodine-131, which was iodogen-labeled.) Measurements were made of the activity concentration in blood and bone marrow at different points in time after injection, and the ratio of activity concentration in red marrow and blood as a function of time postinjection (RMBLR[t)]) was calculated. For patients treated with iodine-131-labeled monoclonal antibody (LL2, Immunomedics Inc., Morris Plains, NJ; anti-CD22; immunoglobulin G2 isotype of mouse origin), blood samples were drawn and scintillation camera images taken at different times after injection. The red marrow activity concentration in the sacrum was determined by activity quantification from regions of interest. The activity concentration in blood was also measured. The RMBLR(t) was calculated based on these data. RESULTS: For both patients and rats, the RMBLR(t) was increased 72 hours after injection. Furthermore, it was found that the use of a constant RMBLR can lead to an over- or underestimation of the absorbed dose in bone marrow. CONCLUSIONS: These data demonstrate the difficulty in using fixed values of the activity concentration ratio of red marrow to blood for dosimetry. (Less)
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organization
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Contribution to journal
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published
subject
keywords
Animal, Bone Marrow/*metabolism, Dose-Response Relationship, Radiation, Human, Models, Radiation Dosage, Radioisotopes/*blood/metabolism, Radioimmunotherapy/*methods, Radiometry/methods, Rats, Non-U.S. Gov't, Time Factors, Support
in
Cancer
volume
94
issue
4 Suppl
pages
1235 - 1239
publisher
John Wiley & Sons
external identifiers
  • pmid:11877751
  • wos:000173958100008
  • scopus:0037083396
ISSN
1097-0142
DOI
10.1002/cncr.10291
language
English
LU publication?
yes
id
77fce6e6-f63c-4cd4-b670-355627b7654b (old id 106386)
alternative location
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11877751&dopt=Abstract
date added to LUP
2007-07-19 16:12:45
date last changed
2017-01-01 04:19:53
@article{77fce6e6-f63c-4cd4-b670-355627b7654b,
  abstract     = {BACKGROUND: The method for red marrow dosimetry in radioimmunotherapy, in the absence of specific activity uptake in red marrow, is based on the activity measured in the blood or plasma. The activity concentration ratio of red marrow to blood is then assumed to be constant. The aim of the current study was to determine whether this ratio varies with time after injection. METHODS: Measurements were carried out with both animals and patients.Tumor-bearing rats were intravenously injected with iodine-131-, iodine-125-, indium-111-, or rhenium-188-labeled BR96, a chimeric immunoglobulin G1 monoclonal antibody. (All were chelate-labeled, except for iodine-131, which was iodogen-labeled.) Measurements were made of the activity concentration in blood and bone marrow at different points in time after injection, and the ratio of activity concentration in red marrow and blood as a function of time postinjection (RMBLR[t)]) was calculated. For patients treated with iodine-131-labeled monoclonal antibody (LL2, Immunomedics Inc., Morris Plains, NJ; anti-CD22; immunoglobulin G2 isotype of mouse origin), blood samples were drawn and scintillation camera images taken at different times after injection. The red marrow activity concentration in the sacrum was determined by activity quantification from regions of interest. The activity concentration in blood was also measured. The RMBLR(t) was calculated based on these data. RESULTS: For both patients and rats, the RMBLR(t) was increased 72 hours after injection. Furthermore, it was found that the use of a constant RMBLR can lead to an over- or underestimation of the absorbed dose in bone marrow. CONCLUSIONS: These data demonstrate the difficulty in using fixed values of the activity concentration ratio of red marrow to blood for dosimetry.},
  author       = {Hindorf, Cecilia and Lindén, Ola and Tennvall, Jan and Wingårdh, Karin and Strand, Sven-Erik},
  issn         = {1097-0142},
  keyword      = {Animal,Bone Marrow/*metabolism,Dose-Response Relationship,Radiation,Human,Models,Radiation Dosage,Radioisotopes/*blood/metabolism,Radioimmunotherapy/*methods,Radiometry/methods,Rats,Non-U.S. Gov't,Time Factors,Support},
  language     = {eng},
  number       = {4 Suppl},
  pages        = {1235--1239},
  publisher    = {John Wiley & Sons},
  series       = {Cancer},
  title        = {Time dependence of the activity concentration ratio of red marrow to blood and implications for red marrow dosimetry.},
  url          = {http://dx.doi.org/10.1002/cncr.10291},
  volume       = {94},
  year         = {2002},
}