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Blakkisrud J, Peterson AB, Wildermann SJ, Kingkiner G, Wong KK, Wang C, Frey KA, Stokke C, Dewaraja YK. SPECT/CT Image-Derived Absorbed Dose to Red Marrow Correlates with Hematologic Toxicity in Patients Treated with [ 177Lu]Lu-DOTATATE. J Nucl Med 2024; 65:753-760. [PMID: 38548350 PMCID: PMC11064826 DOI: 10.2967/jnumed.123.266843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 02/21/2024] [Indexed: 05/03/2024] Open
Abstract
Hematologic toxicity, although often transient, is the most common limiting adverse effect during somatostatin peptide receptor radionuclide therapy. This study investigated the association between Monte Carlo-derived absorbed dose to the red marrow (RM) and hematologic toxicity in patients being treated for their neuroendocrine tumors. Methods: Twenty patients each receiving 4 treatment cycles of [177Lu]Lu-DOTATATE were included. Multiple-time-point 177Lu SPECT/CT imaging-based RM dosimetry was performed using an artificial intelligence-driven workflow to segment vertebral spongiosa within the field of view (FOV). This workflow was coupled with an in-house macroscale/microscale Monte Carlo code that incorporates a spongiosa microstructure model. Absorbed dose estimates to RM in lumbar and thoracic vertebrae within the FOV, considered as representations of the whole-body RM absorbed dose, were correlated with hematologic toxicity markers at about 8 wk after each cycle and at 3- and 6-mo follow-up after completion of all cycles. Results: The median of absorbed dose to RM in lumbar and thoracic vertebrae within the FOV (D median,vertebrae) ranged from 0.019 to 0.11 Gy/GBq. The median of cumulative absorbed dose across all 4 cycles was 1.3 Gy (range, 0.6-2.5 Gy). Hematologic toxicity was generally mild, with no grade 2 or higher toxicity for platelets, neutrophils, or hemoglobin. However, there was a decline in blood counts over time, with a fractional value relative to baseline at 6 mo of 74%, 97%, 57%, and 97%, for platelets, neutrophils, lymphocytes, and hemoglobin, respectively. Statistically significant correlations were found between a subset of hematologic toxicity markers and RM absorbed doses, both during treatment and at 3- and 6-mo follow-up. This included a correlation between the platelet count relative to baseline at 6-mo follow up: D median,vertebrae (r = -0.64, P = 0.015), D median,lumbar (r = -0.72, P = 0.0038), D median,thoracic (r = -0.58, P = 0.029), and D average,vertebrae (r = -0.66, P = 0.010), where D median,lumbar and D median,thoracic are median absorbed dose to the RM in the lumbar and thoracic vertebrae, respectively, within the FOV and D average,vertebrae is the mass-weighted average absorbed dose of all vertebrae. Conclusion: This study found a significant correlation between image-derived absorbed dose to the RM and hematologic toxicity, including a relative reduction of platelets at 6-mo follow up. These findings indicate that absorbed dose to the RM can potentially be used to understand and manage hematologic toxicity in peptide receptor radionuclide therapy.
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Affiliation(s)
- Johan Blakkisrud
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, Michigan;
- Department of Physics and Computational Radiology, Oslo University Hospital, Oslo, Norway
| | - Avery B Peterson
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, Michigan
- Department of Radiation Oncology, Wayne State University, Detroit, Michigan
| | - Scott J Wildermann
- Department of Nuclear Engineering and Radiologic Science, University of Michigan, Ann Arbor, Michigan
| | - Griffen Kingkiner
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Ka Kit Wong
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Chang Wang
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, Michigan
- Department of Biostatistics, University of Michigan, Ann Arbor, Michigan; and
| | - Kirk A Frey
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Caroline Stokke
- Department of Physics and Computational Radiology, Oslo University Hospital, Oslo, Norway
- Department of Physics, University of Oslo, Oslo, Norway
| | - Yuni K Dewaraja
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Michigan, Ann Arbor, Michigan
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Quantification of the volume fraction of fat, water and bone mineral in spongiosa for red marrow dosimetry in molecular radiotherapy by using a dual-energy (SPECT/)CT. Z Med Phys 2022; 32:428-437. [PMID: 35292186 PMCID: PMC9948840 DOI: 10.1016/j.zemedi.2022.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/26/2022] [Accepted: 01/30/2022] [Indexed: 11/22/2022]
Abstract
A patient-specific absorbed dose calculation for red marrow dosimetry requires quantifying patient-specific volume fractions of the red marrow, yellow marrow, and trabecular bone in the spongiosa of several skeletal sites. This quantification allows selecting appropriate S values calculated from the parameterized radiation transport models for bone and bone marrow dosimetry. Currently, no comprehensive, individualized, and non-invasive procedure is available for quantifying the volume fractions of red marrow, yellow marrow, and trabecular bone in the spongiosa. This study aims to provide a new quantitative method based on dual-energy computed tomography to fill this gap in red marrow dosimetry using a (SPECT/)CT system. METHODS First, a method for parametrizing the photon attenuation coefficients relative to water was implemented. Next, a method to calculate the effective atomic number (Zeff) and effective mass density (ρeff) using dual-energy CT (DECT) was employed. Lastly, two- and three-material decomposition using a dual-energy quantitative CT method (DEQCT) was performed in an anthropomorphic spine phantom and two bone samples of a boar, respectively. The measurements of Zeff and ρeff were compared with the syngo.CT DE Rho/Z tool (Siemens Healthineers). Furthermore, the DEQCT method implemented in this study (DEQCT-I) was compared with a second DEQCT method based on the use of external material standards (DEQCT-II). DEQCT-II was used as reference method for calculating relative errors. RESULTS The two-material decomposition in the anthropomorphic spine phantom presented a maximum relative error of -10% for the bone mineral density quantification. Furthermore, Zeff and ρeff calculated by DEQCT-I differed from syngo.CT DE Rho/Z tool by less than 4.4% and 1.9%, respectively. The three-material decomposition in the two bone samples showed a maximum relative error of 21%, -17%, and 15% for the quantification of the volume fractions of fat, water, and bone mineral equivalent materials. Lastly, Zeff and ρeff calculated by DEQCT-I differed from syngo.CT DE Rho/Z tool by less than 8.2% and 7.0%, respectively. CONCLUSION This study shows that quantifying the volume fraction of fat, water, and bone mineral using a phantom-independent and post-reconstruction DEQCT method is feasible. DEQCT-I has the advantage of not requiring prior information about the X-ray spectra or the detector sensitivity function, as is the case with spectral-based DEQCT methods. Instead, DEQCT-I, similar to other DEQCT methods depends on the chemical description of reference materials and a beam hardening correction function. DEQCT-I method provides an individualized and non-invasive procedure using a (SPECT/)CT system to apply S values based on the patient-specific volume fractions of yellow marrow, red marrow, and bone mineral in red marrow dosimetry.
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Warrell GR, Colussi VC, Swanson WL, Caimi PF, Mansur DB, de Lima MJG, Pereira GC. Organ sparing of linac-based targeted marrow irradiation over total body irradiation. J Appl Clin Med Phys 2019; 20:69-79. [PMID: 31605462 PMCID: PMC6839384 DOI: 10.1002/acm2.12742] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/09/2019] [Accepted: 09/11/2019] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Targeted marrow irradiation (TMI) is an alternative conditioning regimen to total body irradiation (TBI) before bone marrow transplantation in hematologic malignancies. Intensity-modulation methods of external beam radiation therapy are intended to permit significant organ sparing while maintaining adequate target coverage, improving the therapeutic ratio. This study directly compares the dose distributions to targets and organs at risk from TMI and TBI, both modalities conducted by general-use medical linacs at our institution. METHODS TMI treatments were planned for 10 patients using multi-isocentric feathered volumetric arc therapy (VMAT) plans, delivered by 6 MV photon beams of Elekta Synergy linacs. The computed tomography (CT) datasets used to obtain these plans were also used to generate dose distributions of TBI treatments given in the AP/PA extended-field method. We compared dose distributions normalized to the same prescription for both plan types. The generalized equivalent uniform dose (gEUD) of Niemierko for organs and target volumes was used to quantify effective whole structure dose and dose savings. RESULTS For the clinical target volume (CTV), no significant differences were found in mean dose or gEUD, although the radical dose homogeneity index (minimum dose divided by maximum dose) was 31.7% lower (P = 0.002) and the standard deviation of dose was 28.0% greater (P = 0.027) in the TMI plans than in the TBI plans. For the TMI plans, gEUD to the lungs, brain, kidneys, and liver was significantly lower (P < 0.001) by 47.8%, 33.3%, 55.4%, and 51.0%, respectively. CONCLUSION TMI is capable of maintaining CTV coverage as compared to that achieved in TBI, while significantly sparing organs at risk. Improvement on sparing organs at risk permits a higher prescribed dose to the target or the maximum number of times marrow conditioning may be delivered to a patient while maintaining similar typical tissue complication rates.
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Affiliation(s)
| | | | - Wayne L. Swanson
- Department of Radiation OncologyUniversity HospitalsClevelandOHUSA
| | - Paolo F. Caimi
- Department of Medicine–Hematology and OncologyUniversity HospitalsClevelandOHUSA
| | - David B. Mansur
- Department of Radiation OncologyUniversity HospitalsClevelandOHUSA
| | - Marcos J. G. de Lima
- Department of Medicine–Hematology and OncologyUniversity HospitalsClevelandOHUSA
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Salas-Ramirez M, Tran-Gia J, Gbureck U, Kosmala A, Lassmann M. Quantification of the trabecular bone volume fraction for bone marrow dosimetry in molecular radiotherapy by using a dual-energy (SPECT/)CT. Phys Med Biol 2019; 64:205014. [PMID: 31519000 DOI: 10.1088/1361-6560/ab4476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A complete characterization of spongiosa (bone marrow plus trabecular bone) is required to calculate the absorbed dose to active bone marrow. Due to the complex microanatomy, it is necessary to apply non-conventional imaging methods in nuclear medicine. The aim of this study is validating a phantomless quantification method using dual-energy quantitative computed tomography (DEQCT) for the quantification of trabecular bone volume fraction for bone marrow dosimetry in molecular radiotherapy. First, a phantomless quantification method (mass fraction method) based on x-ray beam and detector sensitivity was validated in an integrated dual energy SPECT/CT and in a dual source computed tomography (DSCT) system for comparison. The validation was performed in a phantom consisting of different water, fat and hydroxyapatite compositions. Moreover, the European spine phantom (ESP) was used to simulate the spine geometry. Bone mineral content (BMC) of the whole vertebra and bone mineral density (BMD) in the spongiosa region of each phantom vertebra were measured using DEQCT and dual energy x-ray absorptiometry (DEXA). Lastly, BMC was measured in a patient using DEQCT and DEXA. Measured values of hydroxyapatite fraction and nominal values in the homemade phantom showed a good correlation. The relative error remained below 14.2%. Quantification of BMC (in whole vertebra) and BMD (in spongiosa) in the ESP showed a good agreement between measured values and nominal values. The relative error remained between 0.7% and 7.5% for BMCSPECT/CT, 1.1% and 7.7% for BMCDSCT, 5.4% and 32.0 for BMDSPECT/CT, and 59.4% and 10.0% for BMDDSCT. Quantification of BMC in lumbar vertebrae 1 and 2 of a patient showed relative errors of 7.6% and -8.4% between DEXA and DSCT. Our study shows that DEQCT using a mass fraction method (phantomless) enables quantification of hydroxyapatite in a clinical nuclear medicine setting. An overestimation of the hydroxyapatite volume fraction was observed in all quantified regions, in particular in the spongiosa region of ESP. This result might be related to insufficient information about the x-ray spectra and the detector sensitivity function.
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Salas-Ramirez M, Tran-Gia J, Kesenheimer C, Weng AM, Kosmala A, Heidemeier A, Köstler H, Lassmann M. Quantification of fat fraction in lumbar vertebrae: correlation with age and implications for bone marrow dosimetry in molecular radiotherapy. ACTA ACUST UNITED AC 2018; 63:025029. [DOI: 10.1088/1361-6560/aa9a28] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Geyer AM, Schwarz BC, Hobbs RF, Sgouros G, Bolch WE. Quantitative impact of changes in marrow cellularity, skeletal size, and bone mineral density on active marrow dosimetry based upon a reference model. Med Phys 2017; 44:272-283. [PMID: 28102950 DOI: 10.1002/mp.12002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 09/14/2016] [Accepted: 10/30/2016] [Indexed: 11/10/2022] Open
Abstract
PURPOSE The hematopoietically active tissues of skeletal bone marrow are a prime target for computational dosimetry given potential risks of leukemia and, at higher dose levels, acute marrow toxicity. The complex three-dimensional geometry of trabecular spongiosa, however, complicates schema for dose assessment in such a way that only a few reference skeletal models have been developed to date, and which are based upon microimaging of a limited number of cadaveric bone spongiosa cores. The question then arises as to what degree of accuracy is achievable from reference skeletal dose models when applied to individual patients or specific exposed populations? METHODS Patient variability in marrow dosimetry were quantified for three skeletal sites - the ribs, lumbar vertebrae, and cranium - for the beta-emitters 45 Ca, 153 Sm, and 90 Y, and the alpha-particle emitters 223 Ra, 219 Rn, and 215 Po, the latter two being the immediate progeny of the former. For each radionuclide and bone site, three patient parameters were altered from their values in the reference model: (1) bone size as a surrogate for patient stature, (2) marrow cellularity as a surrogate for age- or disease-related changes in marrow adiposity, and (3) the trabecular bone volume fraction as a surrogate for bone mineral density. Marrow dose variability is expressed as percent differences in the radionuclide S value given by the reference model and the patient-parameterized model. The impact of radionuclide biokinetics on marrow dosimetry was not considered. RESULTS Variations in overall bone size play a very minor role in active marrow dose variability. Marrow cellularity is a significant factor in dose variability for active marrow self-irradiation, but it plays no role for radionuclides localized to the trabecular bone matrix. Variations in trabecular bone volume fractions impact the active marrow dose variability for short-range particle emitters 45 Ca, 223 Ra, 219 Rn, and 215 Po in the vertebrae and ribs, skeletal sites with small spongiosa proportions of trabecular bone. In the cranium, with its relative high proportion of trabecular bone, significant differences in marrow dosimetry from the reference model were noted for all radionuclides. CONCLUSIONS Skeletal models of active marrow dosimetry should be more fully parameterized to permit closer matching to patient bone density and marrow cellularity, particularly when considering short-range particle emitters localized to either the bone trabeculae or active marrow, respectively.
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Affiliation(s)
- Amy M Geyer
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, 32611-6131, USA
| | - Bryan C Schwarz
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, 32611-6131, USA
| | - Robert F Hobbs
- Department of Radiation Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
| | - George Sgouros
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
| | - Wesley E Bolch
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, 32611-6131, USA
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Goodsitt MM, Shenoy A, Shen J, Howard D, Schipper MJ, Wilderman S, Christodoulou E, Chun SY, Dewaraja YK. Evaluation of dual energy quantitative CT for determining the spatial distributions of red marrow and bone for dosimetry in internal emitter radiation therapy. Med Phys 2014; 41:051901. [PMID: 24784380 DOI: 10.1118/1.4870378] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To evaluate a three-equation three-unknown dual-energy quantitative CT (DEQCT) technique for determining region specific variations in bone spongiosa composition for improved red marrow dose estimation in radionuclide therapy. METHODS The DEQCT method was applied to 80/140 kVp images of patient-simulating lumbar sectional body phantoms of three sizes (small, medium, and large). External calibration rods of bone, red marrow, and fat-simulating materials were placed beneath the body phantoms. Similar internal calibration inserts were placed at vertebral locations within the body phantoms. Six test inserts of known volume fractions of bone, fat, and red marrow were also scanned. External-to-internal calibration correction factors were derived. The effects of body phantom size, radiation dose, spongiosa region segmentation granularity [single (∼17 × 17 mm) region of interest (ROI), 2 × 2, and 3 × 3 segmentation of that single ROI], and calibration method on the accuracy of the calculated volume fractions of red marrow (cellularity) and trabecular bone were evaluated. RESULTS For standard low dose DEQCT x-ray technique factors and the internal calibration method, the RMS errors of the estimated volume fractions of red marrow of the test inserts were 1.2-1.3 times greater in the medium body than in the small body phantom and 1.3-1.5 times greater in the large body than in the small body phantom. RMS errors of the calculated volume fractions of red marrow within 2 × 2 segmented subregions of the ROIs were 1.6-1.9 times greater than for no segmentation, and RMS errors for 3 × 3 segmented subregions were 2.3-2.7 times greater than those for no segmentation. Increasing the dose by a factor of 2 reduced the RMS errors of all constituent volume fractions by an average factor of 1.40 ± 0.29 for all segmentation schemes and body phantom sizes; increasing the dose by a factor of 4 reduced those RMS errors by an average factor of 1.71 ± 0.25. Results for external calibrations exhibited much larger RMS errors than size matched internal calibration. Use of an average body size external-to-internal calibration correction factor reduced the errors to closer to those for internal calibration. RMS errors of less than 30% or about 0.01 for the bone and 0.1 for the red marrow volume fractions would likely be satisfactory for human studies. Such accuracies were achieved for 3 × 3 segmentation of 5 mm slice images for: (a) internal calibration with 4 times dose for all size body phantoms, (b) internal calibration with 2 times dose for the small and medium size body phantoms, and (c) corrected external calibration with 4 times dose and all size body phantoms. CONCLUSIONS Phantom studies are promising and demonstrate the potential to use dual energy quantitative CT to estimate the spatial distributions of red marrow and bone within the vertebral spongiosa.
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Affiliation(s)
- Mitchell M Goodsitt
- Department of Radiology, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109
| | - Apeksha Shenoy
- Department of Radiology, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109
| | - Jincheng Shen
- Department of Biostatistics, University of Michigan, 1415 Washington Heights, Ann Arbor, Michigan 48109
| | - David Howard
- Department of Radiology, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109
| | - Matthew J Schipper
- Department of Radiation Oncology, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109
| | - Scott Wilderman
- Department of Nuclear Engineering, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109
| | - Emmanuel Christodoulou
- Department of Radiology, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109
| | - Se Young Chun
- Ulsan National Institute of Science and Technology (UNIST), School of Electrical and Computer Engineering, Ulsan 689-798, Republic of Korea
| | - Yuni K Dewaraja
- Department of Radiology, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109
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Dewaraja YK, Schipper MJ, Shen J, Smith LB, Murgic J, Savas H, Youssef E, Regan D, Wilderman SJ, Roberson PL, Kaminski MS, Avram AM. Tumor-Absorbed Dose Predicts Progression-Free Survival Following (131)I-Tositumomab Radioimmunotherapy. J Nucl Med 2014; 55:1047-53. [PMID: 24842891 PMCID: PMC4237694 DOI: 10.2967/jnumed.113.136044] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 03/21/2014] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The study aimed at identifying patient-specific dosimetric and nondosimetric factors predicting outcome of non-Hodgkin lymphoma patients after (131)I-tositumomab radioimmunotherapy for potential use in treatment planning. METHODS Tumor-absorbed dose measures were estimated for 130 tumors in 39 relapsed or refractory non-Hodgkin lymphoma patients by coupling SPECT/CT imaging with the Dose Planning Method (DPM) Monte Carlo code. Equivalent biologic effect was calculated to assess the biologic effects of nonuniform absorbed dose including the effects of the unlabeled antibody. Evaluated nondosimetric covariates included histology, presence of bulky disease, and prior treatment history. Tumor level outcome was based on volume shrinkage assessed on follow-up CT. Patient level outcome measures were overall response (OR), complete response (CR), and progression-free survival (PFS), determined from clinical assessments that included PET/CT. RESULTS The estimated mean tumor-absorbed dose had a median value of 275 cGy (range, 94-711 cGy). A high correlation was observed between tracer-predicted and therapy-delivered mean tumor-absorbed doses (P < 0.001; r = 0.85). In univariate tumor-level analysis, tumor shrinkage correlated significantly with almost all of the evaluated dosimetric factors, including equivalent biologic effect. Regression analysis showed that OR, CR, and PFS were associated with the dosimetric factors and equivalent biologic effect. Both mean tumor-absorbed dose (P = 0.025) and equivalent biologic effect (P = 0.035) were significant predictors of PFS whereas none of the nondosimetric covariates were found to be statistically significant factors affecting PFS. The most important finding of the study was that in Kaplan-Meier curves stratified by mean dose, longer PFS was observed in patients receiving mean tumor-absorbed doses greater than 200 cGy than in those receiving 200 cGy or less (median PFS, 13.6 vs. 1.9 mo for the 2 dose groups; log-rank P < 0.0001). CONCLUSION A higher mean tumor-absorbed dose was significantly predictive of improved PFS after (131)I-tositumomab radioimmunotherapy. Hence tumor-absorbed dose, which can be estimated before therapy, can potentially be used to design radioimmunotherapy protocols to improve efficacy.
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Affiliation(s)
- Yuni K Dewaraja
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Matthew J Schipper
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
| | - Jincheng Shen
- Department of Biostatistics, University of Michigan, Ann Arbor, Michigan
| | - Lauren B Smith
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Jure Murgic
- Department of Oncology and Nuclear Medicine, University Hospital Center Sestre Milosrdnice, Zagreb, Croatia
| | - Hatice Savas
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Ehab Youssef
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Denise Regan
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Scott J Wilderman
- Department of Nuclear Engineering, University of Michigan, Ann Arbor, Michigan; and
| | - Peter L Roberson
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
| | - Mark S Kaminski
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
| | - Anca M Avram
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
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