TY - JOUR
T1 - Estimation of yttrium-90 Zevalin tumor-absorbed dose in ocular adnexal lymphoma using quantitative indium-111 Zevalin radionuclide imaging
AU - Erwin, William D.
AU - Esmaeli, Bita
N1 - Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2009/9
Y1 - 2009/9
N2 - OBJECTIVE: The purpose of this investigation was to estimate radiation-absorbed dose in orbital tumors from yttrium-90 ibritumomab tiuxetan (Zevalin) radioimmunotherapy of ocular adnexal lymphoma. METHODS: Three patients participating in a prospective research protocol involving treatment of ocular adnexal lymphoma with yttrium-90 Zevalin consented to quantitative radionuclide imaging to estimate tumor radiation-absorbed doses. Each patient received 185 MBq of indium-111 Zevalin, followed by serial planar whole-body scanning, to derive an activity versus time curve for the tumor. Single photon emission computed tomography (SPECT) and computed tomography (CT) imaging, including a calibration source, were performed at 24 h on a SPECT/CT scanner, to obtain a SPECT estimate of the radioactivity (in megabequerels) in the tumor and correct the planar curve, as well as estimate the tumor mass (M) from CT. The curve was then converted to that for yttrium-90 at the prescribed activity, and absorbed dose estimated from the area under the curve multiplied by the Medical Internal Radiation Dose S value (Gy per MBq-h) for a sphere of mass M. RESULTS: A right orbital tumor in one patient was visualized in both the planar and SPECT/CT images, with an estimated absorbed dose of 3.57 Gy. Tumor uptake in the other two patients was not visualized. CONCLUSION: The radiation dose to the orbit and ocular structures during radioimmunotherapy of ocular adnexal lymphoma is well below the threshold for significant radiation-induced ocular toxicity and about 10 times lower than that delivered during external beam radiotherapy.
AB - OBJECTIVE: The purpose of this investigation was to estimate radiation-absorbed dose in orbital tumors from yttrium-90 ibritumomab tiuxetan (Zevalin) radioimmunotherapy of ocular adnexal lymphoma. METHODS: Three patients participating in a prospective research protocol involving treatment of ocular adnexal lymphoma with yttrium-90 Zevalin consented to quantitative radionuclide imaging to estimate tumor radiation-absorbed doses. Each patient received 185 MBq of indium-111 Zevalin, followed by serial planar whole-body scanning, to derive an activity versus time curve for the tumor. Single photon emission computed tomography (SPECT) and computed tomography (CT) imaging, including a calibration source, were performed at 24 h on a SPECT/CT scanner, to obtain a SPECT estimate of the radioactivity (in megabequerels) in the tumor and correct the planar curve, as well as estimate the tumor mass (M) from CT. The curve was then converted to that for yttrium-90 at the prescribed activity, and absorbed dose estimated from the area under the curve multiplied by the Medical Internal Radiation Dose S value (Gy per MBq-h) for a sphere of mass M. RESULTS: A right orbital tumor in one patient was visualized in both the planar and SPECT/CT images, with an estimated absorbed dose of 3.57 Gy. Tumor uptake in the other two patients was not visualized. CONCLUSION: The radiation dose to the orbit and ocular structures during radioimmunotherapy of ocular adnexal lymphoma is well below the threshold for significant radiation-induced ocular toxicity and about 10 times lower than that delivered during external beam radiotherapy.
KW - Ocular adnexal lymphoma
KW - Ocular radiotoxicity
KW - Quantitative radionuclide imaging
KW - Quantitative single photon emission computed tomography
KW - Radioimmunotherapy
KW - Tumor dosimetry
KW - Zevalin
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U2 - 10.1097/MNM.0b013e32832a6e4d
DO - 10.1097/MNM.0b013e32832a6e4d
M3 - Article
C2 - 19528874
AN - SCOPUS:68249133777
SN - 0143-3636
VL - 30
SP - 681
EP - 686
JO - Nuclear medicine communications
JF - Nuclear medicine communications
IS - 9
ER -