Bradford J Wood

National Institutes of Health, 베서스다, Maryland, United States

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Publications (281)1048.76 Total impact

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    ABSTRACT: Purpose: Patients with metastatic or relapsed pediatric sarcomas receive cytotoxic regimens that induce high remission rates associated with profound lymphocyte depletion, but ultimately few survive long-term. We administered adjuvant immunotherapy to patients with metastatic and recurrent pediatric sarcomas in an effort to improve outcomes. Experimental design: Mononuclear cells were collected via apheresis and tumor lysate was acquired via percutaneous biopsy at enrollment. Participants received standard anti-neoplastic therapy, followed by autologous lymphocytes, tumor lysate/KLH pulsed dendritic cell vaccinations ± recombinant human interleukin-7. Primary outcomes were toxicity and vaccine responses. Secondary outcomes were immune reconstitution, EFS and OS. Results: Forty-three patients enrolled and 29 received immunotherapy. The regimen was well tolerated. Intent-to-treat analysis demonstrated 5-yr OS of 51% with significant differences based upon histologic group (63% vs 0% for Ewing/rhabdomyosarcoma vs other sarcomas) and response to standard therapy (74% no residual disease vs 0% residual disease). 5-yr intent-to-treat OS of patients with newly diagnosed metastatic Ewing/rhabdomyosarcoma was 77%, higher than previously reported in this population and higher than observed in a similar group treated with an earlier adjuvant immunotherapy regimen (25% 5-yr OS). T cell responses to autologous tumor lysate were identified in 62% of immunotherapy recipients and survival was higher in those patients (73% 5-yr OS with vs 37% without immune response, p=.017). Immune reconstitution, measured by CD4 count recovery, was significantly enhanced in subjects treated with recombinant human interleukin-7. Conclusion: Adjuvant immunotherapy may improve survival in patients with metastatic pediatric sarcoma.
    No preview · Article · Jan 2016 · Clinical Cancer Research
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    ABSTRACT: Introduction: As the adoption of MRI/US fusion-guided biopsy (FB) expands, the reproducibility of outcomes from expert centers becomes essential. The objective of our study was to validate the comprehensive National Cancer Institute (NCI) experience of multiparametric MRI and FB with an external, independent, matched cohort of patients. Methods: We compared 620 patients enrolled in a prospective trial comparing systematic biopy (SB) to FB at the NCI to 310 patients that underwent a similar procedure at Long Island Jewish Hospital (LIJ). The propensity score, defined as the probability of being treated outside NCI, was calculated using the estimated logistic regression model. Patients from LIJ were matched 1:1 for age, PSA, MRI suspicion score, and prior negative biopsies. Clinically significant (CS) disease was defined as Gleason ≥3+4. Results: Prior to matching, we found differences between cohorts in age (p<0.001), MRI suspicion score (p<0.001), the number of patients with prior negative biopsies (p=0.01), and both overall CDR (<0.001) and CDR by FB (p<0.001). No difference was found in the rates of upgrading by FB (p=0.28) and upgrading to CS disease (p=0.95). After matching, a statistically significant difference remained in CDR and CDR by FB. On subgroup analysis, we found a difference in CDR (p<0.001) and CDR by FB (p=0.003) in patients with prior negative SB and no difference in CDR (p=0.39) and CDR by FB (p=0.51) in biopsy naïve patients. Conclusions: Improved detection of CS cancer by MRI and FB is reproducible with an experienced multi-disciplinary team consisting of dedicated radiologists and urologists.
    Full-text · Article · Jan 2016 · The Journal of urology
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    ABSTRACT: Objective: The aim of this study was to evaluate the value of quantitative diffusion and perfusion parameters to aid in discriminating between transition zone carcinomas and benign prostatic hyperplasia (BPH). Materials and methods: Twenty-four transition zone cancers and BPH nodules were contoured on T2-weighted magnetic resonance imaging (MRI), apparent diffusion coefficient (ADC) maps, and raw dynamic contrast-enhanced (DCE) MRI. Benign prostatic hyperplasia nodules were then stratified into 2 groups based on the presence or absence of a capsule. Apparent diffusion coefficient values, per-voxel Ktrans, kep, vp, and ve were all compared across all groups. Results: Average ADCs (×10 mm/s) were 1019.22, 1338.11, and 1272.46 for cancer, encapsulated BPH, and nonencapsulated BPH, respectively. Both subgroups of BPH were found to be significantly different than that of cancer (P < 0.05). No individual DCE-MRI parameter was significantly different between cancer and either BPH group. The area under the curve for ADC alone was 0.83, and no individual DCE imaging parameter improved the area under the curve of ADC. Conclusions: Apparent diffusion coefficient may play a role in distinguishing TZ cancers from non-encapsulated BPH nodules that closely resemble cancer.
    Full-text · Article · Jan 2016 · Journal of computer assisted tomography
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    ABSTRACT: DCE MRI is an established component of multi-parametric MRI of the prostate. The sequence highlights the vascularization of cancerous lesions, allowing readers to corroborate suspicious findings on T2W and DW MRI and to note subtle lesions not visible on the other sequences. In this article, we review the technical aspects, methods of evaluation, limitations, and future perspectives of DCE MRI.
    Full-text · Article · Jan 2016
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    ABSTRACT: Purpose: Embolotherapy using microshperes is currently performed with soluble contrast to aid in visualization. However, administered payload visibility dimishes soon after delivery due to soluble contrast washout, leaving the radiolucent bead's location unknown. The objective of our study was to characterize inherently radiopaque beads (RO Beads) in terms of physicomechanical properties, deliverability and imaging visibility in a rabbit VX2 liver tumor model. Materials and Methods: RO Beads, which are based on LC Bead (R) platform, were compared to LC Bead. Bead size (light microscopy), equilibrium water content (EWC), density, X-ray attenuation and iodine distribution (micro-CT), suspension (settling times), deliverability and in vitro penetration were investigated. Fifteen rabbits were embolized with either LC Bead or RO Beads + soluble contrast (iodixanol-320), or RO Beads+dextrose. Appearance was evaluated with fluoroscopy, X-ray single shot, cone-beam CT (CBCT). Results: Both bead types had a similar size distribution. RO Beads had lower EWC (60-72%) and higher density (1.21-1.36 g/cc) with a homogeneous iodine distribution within the bead's interior. RO Beads suspension time was shorter than LC Bead, with durable suspension (>5 min) in 100% iodixanol. RO Beads <= 300 mu m were deliverable through a 2.3-Fr microcatheter. Both bead types showed similar penetration. Soluble contrast could identify target and non-target embolization on fluoroscopy during administration. However, the imaging appearance vanished quickly for LC Bead as contrast washed-out. RO Beads+contrast significantly increased visibility on X-ray single shot compared to LC Bead+contrast in target and non-target arteries (P=0.0043). Similarly, RO beads demonstrated better visibility on CBCT in target arteries (P=0.0238) with a trend in non-target arteries (P=0.0519). RO Beads+dextrose were not sufficiently visible to monitor embolization using fluoroscopy. Conclusion: RO Beads provide better conspicuity to determine target and non-target embolization compared to LC Bead which may improve intra-procedural monitoring and post-procedural evaluation of transarterial embolization.
    Full-text · Article · Jan 2016 · Theranostics
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    ABSTRACT: Purpose To assess the visibility of radiopaque microspheres during transarterial embolization (TAE) in the VX2 rabbit liver tumor model by using multimodality imaging, including single-snapshot radiography, cone-beam computed tomography (CT), multidetector CT, and micro-CT. Materials and Methods The study was approved by the institutional animal care and use committee. Fifteen VX2-tumor-bearing rabbits were assigned to three groups depending on the type of embolic agent injected: 70-150-μm radiopaque microspheres in saline (radiopaque microsphere group), 70-150-μm radiopaque microspheres in contrast material (radiopaque microsphere plus contrast material group), and 70-150-μm radiolucent microspheres in contrast material (nonradiopaque microsphere plus contrast material group). Rabbits were imaged with single-snapshot radiography, cone-beam CT, and multidetector CT. Three to 5 weeks after sacrifice, excised livers were imaged with micro-CT and histologic analysis was performed. The visibility of the embolic agent was assessed with all modalities before and after embolization by using a qualitative three-point scale score reading study and a quantitative assessment of the signal-to-noise ratio (SNR) change in various regions of interest, including the tumor and its feeding arteries. The Kruskal-Wallis test was used to compare the rabbit characteristics across groups, and the Wilcoxon signed rank test was used to compare SNR measurements before and after embolization. Results Radiopaque microspheres were qualitatively visualized within tumor feeding arteries and targeted tissue with all imaging modalities (P < .05), and their presence was confirmed with histologic examination. SNRs of radiopaque microsphere deposition increased after TAE on multidetector CT, cone-beam CT, and micro-CT images (P < .05). Similar results were obtained when contrast material was added to radiopaque microspheres, except for additional image attenuation due to tumor enhancement. For the group with nonradiopaque microspheres and contrast material, retained tumoral contrast remained qualitatively visible with all modalities except for micro-CT, which demonstrated soluble contrast material washout over time. Conclusion Radiopaque microspheres were visible with all imaging modalities and helped increase conspicuity of the tumor as well as its feeding arteries after TAE in a rabbit VX2 liver tumor model. (©) RSNA, 2015.
    Full-text · Article · Dec 2015 · Radiology
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    ABSTRACT: Clinical use of DC Bead™ loaded with doxorubicin (DEBDOX™) or irinotecan (DEBIRI™), for the treatment of primary and secondary tumours of the liver respectively, is showing great promise. Recently there has been a tendency to select smaller bead size ranges to treat tumours in an effort to allow more drug dose to be administered, improve tumoural penetration and resultant drug delivery and tumour coverage. Herein we describe the development and performance characterisation of a new DC Bead size range (DC BeadM1 TM, 70–150 μm) capable of an increased bead delivery in the distal vasculature, corresponding to greater tumour coverage and drug dose delivered. Both unloaded and drug loaded DC BeadM1 were shown to have a greater density of distal volume of penetration although the ultimate distal level of penetration was the same as that of the 100–300 µm beads in an in vitro penetration model. Elution of doxorubicin was slower than irinotecan elution, but it was similar when comparing the same drug elution from 70 to 150 µm compared to 100–300 µm beads. Radiopaque versions of 70–150 and 100–300 µm beads were prepared in order to evaluate distribution ex vivo using µ-CT and doxorubicin distribution using epifluorescent microscopy. Liver distribution of the radiopaque versions of the beads was shown to be more distal and efficient at filling smaller vessels with the DC BeadM1 and correspondingly more beads were found per vessel histologically with a larger area of drug coverage with the smaller size range. This study indicates that the smaller (70–150 μm) beads should permit an increased dose of drug to be administered to both hypervascular and hypovascular tumours as compared to 100–300 µm beads.
    Full-text · Article · Dec 2015 · Journal of Materials Science Materials in Medicine
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    ABSTRACT: Objectives: To validate the use of biparametric (T2- and diffusion weighted) magnetic resonance imaging (B-MRI) and prostate-specific antigen (PSA)/PSA density (PSAD) in a biopsy naïve cohort at risk for prostate cancer (PCa). Methods: All patients (n=59) underwent PSA screening and digital rectal exam (DRE) prior to a B-MRI followed by MRI/transrectal ultrasound (TRUS) fusion-guided targeted biopsy. Previously reported composite formulas incorporating screen positive lesions (SPL) on B-MRI and PSA or PSAD were developed to maximize PCa detection. For PSA, a patient was considered screen positive if PSA level + 6 x (the number of SPL) >14. For PSAD, screening was positive if PSAD x 14 + (the number of SPL) >4.25. These were employed in this new test set to validate the initial formulae. Performance assessment of these formulas was determined for all cancer detection and for tumors with Gleason ≥3+4. Results: SPL on B-MRI had the highest sensitivity (95.5%) and negative predictive value (NPV) of 71.4% compared to PSA and PSAD. B-MRI significantly improved sensitivity (43.2 to 72.7%, p=0.0002) when combined with PSAD. The NPV of PSA increased with B-MRI, achieving 91.7% for B-MRI and PSA for Gleason ≥3+4. Overall accuracy of the composite equations was 81.4% (B-MRI and PSA) and 78.0% (B-MRI and PSAD). Conclusions: Validation with a biopsy naïve cohort demonstrates the parameter SPL performed better than PSA or PSAD alone in accurately detecting PCa. The combined use of B-MRI, PSA, and PSAD resulted in improved accuracy for detecting clinically significant PCa.
    Full-text · Article · Dec 2015 · Urology
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    ABSTRACT: In order to ensure safe magnetic resonance-guided, high-intensity focused, ultrasound ablation of uterine leiomyomas, the ultrasound beam path should be free of intervening scar and bowel. Pre-treatment MRI of a 9-cm long and 7.7-cm wide leiomyomatous uterus in a 39-year-old woman with menorrhagia and abdominopelvic pain initially demonstrated a focused ultrasound treatment path without a bowel between the uterus and the abdominal wall. On the day of ablation, however, multiple loops of bowel were observed in the ultrasound beam path by MRI. Uterine repositioning was accomplished with a 76-mm donut vaginal pessary, which anteverted the fundus and successfully displaced the bowel. A vaginal pessary may aid in repositioning an axial or retroverted uterus to enable ablation of uterine leiomyomas.
    No preview · Article · Nov 2015 · Gynecologic and Obstetric Investigation
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    Full-text · Dataset · Nov 2015
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    ABSTRACT: Purpose: To develop a simple method to produce radiopaque drug-eluting microspheres (drug-eluting beads [DEBs]) that could be incorporated into the current clinical transcatheter arterial chemoembolization workflow and evaluate their performance in vitro and in vivo. Materials and methods: An ethiodized oil (Lipiodol; Guerbet, Villepinte, France) and ethanol solution was added to a lyophilized 100-300 µm bead before loading with doxorubicin. These radiopaque drug-eluting beads (DEBs; Biocompatibles UK Ltd, Farnham, United Kingdom) were evaluated in vitro for x-ray attenuation, composition, size, drug loading and elution, and correlation between attenuation and doxorubicin concentration. In vivo conspicuity was evaluated in a VX2 tumor model. Results: Lipiodol was loaded into lyophilized beads using two glass syringes and a three-way stopcock. Maximum bead attenuation was achieved within 30 minutes. X-ray attenuation of radiopaque beads increased linearly (21-867 HU) with the amount of beads (0.4-12.5 vol%; R(2) = 0.9989). Doxorubicin loading efficiency and total amount eluted were similar to DC Bead (Biocompatibles UK Ltd); however, the elution rate was slower for radiopaque DEBs (P < .05). Doxorubicin concentration linearly correlated with x-ray attenuation of radiopaque DEBs (R(2) = 0. 99). Radiopaque DEBs were seen in tumor feeding arteries after administration by fluoroscopy, computed tomography, and micro-computed tomography, and their location was confirmed by histology. Conclusions: A simple, rapid method to produce radiopaque DEBs was developed. These radiopaque DEBs provided sufficient conspicuity to be visualized with x-ray imaging techniques.
    No preview · Article · Nov 2015 · Journal of vascular and interventional radiology: JVIR
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    ABSTRACT: Imaging has traditionally played a minor role in the diagnosis and staging of prostate cancer. However, recent controversies generated by the use of prostate-specific antigen (PSA) screening followed by random biopsy have encouraged the development of new imaging methods for prostate cancer. Multiparametric magnetic resonance imaging (mpMRI) has emerged as the imaging method best able to detect clinically significant prostate cancers and to guide biopsies. Here, the authors explain what mpMRI is and how it is used clinically, especially with regard to high-risk populations, and we discuss the impact of mpMRI on treatment decisions for men with prostate cancer. CA Cancer J Clin 2015. © 2015 American Cancer Society.
    Full-text · Article · Nov 2015 · CA A Cancer Journal for Clinicians
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    ABSTRACT: Purpose: We propose a systematic approach to correlate MRI and digital histopathology in prostate. Methods: T2-weighted (T2W) MRI and diffusion-weighted imaging (DWI) are acquired, and a patient-specific mold (PSM) is designed from the MRI. Following prostatectomy, a whole mount tissue specimen is placed in the PSM and sectioned, ensuring that tissue blocks roughly correspond to MRI slices. Rigid body and thin plate spline deformable registration attempt to correct deformation during image acquisition and tissue preparation and achieve a more complete one-to-one correspondence between MRIs and tissue sections. Each tissue section is stained with hematoxylin and eosin and segmented by adopting a machine learning approach. Utilizing this tissue segmentation and image registration, the density of cellular and tissue components (lumen, nucleus, epithelium, and stroma) is estimated per MR voxel, generating density maps for the whole prostate. Results: This study was approved by the local IRB, and informed consent was obtained from all patients. Registration of tissue specimens and MRIs was aided by the PSM and subsequent image registration. Tissue segmentation was performed using a machine learning approach, achieving [Formula: see text]0.98 AUCs for lumen, nucleus, epithelium, and stroma. Examining the density map of tissue components, significant differences were observed between cancer, benign peripheral zone, and benign prostatic hyperplasia (p value [Formula: see text]5e[Formula: see text]2). Similarly, the signal intensity of the corresponding areas in both T2W MRI and DWI was significantly different (p value [Formula: see text]1e[Formula: see text]10). Conclusions: The proposed approach is able to correlate MRI and digital histopathology of the prostate and is promising as a potential tool to facilitate a more cellular and zonal tissue-based analysis of prostate MRI, based upon a correlative histopathology perspective.
    Full-text · Article · Sep 2015 · International Journal of Computer Assisted Radiology and Surgery
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    ABSTRACT: Approximately 15% of patients who undergo radical prostatectomy (RP) for prostate cancer develop local recurrence, which is heralded by a rise in serum prostate-specific antigen (PSA) levels. Early detection and treatment of recurrence improves the outcome of salvage treatment. We investigated the ability of multiparametric magnetic resonance imaging (mpMRI)-transrectal ultrasound (TRUS) fusion-guided biopsy (FGB) combined with "cognitive biopsy" to confirm local recurrence of prostate cancer after RP. In this retrospective study conducted between January 2010 and December 2014, patients with rising PSA levels after RP who had no known evidence of distant metastases underwent mpMRI including T2-weighted (T2W) imaging, diffusion-weighted imaging, dynamic contrast-enhanced (DCE) MRI at 3 Tesla, and subsequent MRI-ultrasound fusion biopsy with cognitive assistance. The detection rate of locally recurrent disease was determined. A total of 10 patients (mean age = 67y, mean PSA level = 3.44ng/ml) met the inclusion criteria. Of the 10 patients, all had positive findings suspicious for local recurrence on mpMRI per entrance criterion. The most important features on mpMRI were early enhancement on DCE MR images and hypointensity on T2W images. The average lesion diameter on mpMRI was 1.12cm (range: 0.40-2.20cm). All suspicious lesions (16/16, 100%) were positive on T2W MR images, 14 (89%) showed positive features on apparent diffusion coefficient maps of diffusion-weighted images, and 16 (100%) were positive on DCE MR images. MRI-TRUS FGBs were positive in 10/16 lesions (62.5%) and 8/10 (80%) patients. MRI-TRUS FGB with cognitive assistance is able to detect and diagnose locally recurrent lesions after RP, even at low PSA levels. This may facilitate early detection of recurrent disease and improve salvage treatment outcomes. Published by Elsevier Inc.
    Full-text · Article · Aug 2015 · Urologic Oncology

  • No preview · Article · Aug 2015 · CardioVascular and Interventional Radiology
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    ABSTRACT: (18)F-FDG PET/CT is used to characterize many malignancies, but is not recommended for localized prostate cancer. This study explores the value of multi-parametric MRI (mpMRI) in characterizing incidental prostate (18)F-FDG uptake. Thirty-one patients who underwent (18)F-FDG PET/CT for reasons unrelated to prostate cancer and prostate mpMRI were eligible for this retrospective study. The mpMRI included T2-weighted (T2W), dynamic contrast enhancement (DCE), apparent diffusion coefficient (ADC), and MR spectroscopy (MRS) sequences. Fourteen patients were excluded (n = 8 insufficient histopathology, n = 6 radical prostatectomy before PET), and final analysis included 17 patients. A nuclear medicine physician, blinded to clinicopathologic findings, identified suspicious areas and maximum standardized uptake values (SUVmax) on (18)F-FDG PET/CT. Sector-based imaging findings were correlated with annotated histopathology from whole-mount or MRI/transrectal ultrasound fusion biopsy samples. Positive predictive values (PPVs) were estimated using generalized estimating equations with logit link. Results were evaluated with Kruskal-Wallis and Dunn's multiple comparisons tests. The PPV of (18)F-FDG PET alone in detecting prostate cancer was 0.65. Combining (18)F-FDG PET as a base parameter with mpMRI (T2W, DCE, ADC, and MRS) increased the PPV to 0.82, 0.83, 0.83, and 0.94, respectively. All benign lesions had SUVmax < 6. Malignant lesions had higher SUVmax values that correlated with Gleason scores. There was a significant difference in SUVmax per prostate between the Gleason ≥ 4 + 5 and benign categories (p = 0.03). Focal incidental prostate (18)F-FDG uptake has low clinical utility alone, but regions of uptake may harbor high-grade prostate cancer, especially if SUVmax > 6. Using mpMRI to further evaluate incidental (18)F-FDG uptake aids the diagnosis of prostate cancer.
    Full-text · Article · Aug 2015 · Abdominal Imaging
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    ABSTRACT: To quantify changes in tumor microvascular (< 1 mm) perfusion relative to commonly used angiographic endpoints. Rabbit Vx2 liver tumors were embolized with 100-300-μm LC Bead particles to endpoints of substasis or complete stasis (controls were not embolized). Microvascular perfusion was evaluated by delivering two different fluorophore-conjugated perfusion markers (ie, lectins) through the catheter before embolization and 5 min after reaching the desired angiographic endpoint. Tumor microvasculature was labeled with an anti-CD31 antibody and analyzed with fluorescence microscopy for perfusion marker overlap/mismatch. Data were analyzed by analysis of variance and post hoc test (n = 3-5 per group; 18 total). Mean microvascular density was 70 vessels/mm(2) ± 17 (standard error of the mean), and 81% ± 1 of microvasculature (ie, CD31(+) structures) was functionally perfused within viable Vx2 tumor regions. Embolization to the extent of substasis eliminated perfusion in 37% ± 9 of perfused microvessels (P > .05 vs baseline), whereas embolization to the extent of angiographic stasis eliminated perfusion in 56% ± 8 of perfused microvessels. Persistent microvascular perfusion following embolization was predominantly found in the tumor periphery, adjacent to normal tissue. Newly perfused microvasculature was not detected at complete stasis but was observed following embolization to complete angiographic stasis. Nearly half of tumor microvasculature remained patent despite embolization to complete angiographic stasis. The observed preservation of tumor microvasculature perfusion with angiographic endpoints of substasis and stasis may have implications for tumor response to embolotherapy. Published by Elsevier Inc.
    No preview · Article · Aug 2015 · Journal of vascular and interventional radiology: JVIR

  • No preview · Article · Aug 2015 · Cancer Research
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    ABSTRACT: The imaging features of unresectable hepatic malignancies in patients who underwent radiofrequency ablation (RFA) in combination with lyso-thermosensitive liposomal doxorubicin (LTLD) were determined. A phase I dose escalation study combining RFA with LTLD was performed with peri- and post- procedural CT and MRI. Imaging features were analyzed and measured in terms of ablative zone size and surrounding penumbra size. The dynamic imaging appearance was described qualitatively immediately following the procedure and at 1-month follow-up. The control group receiving liver RFA without LTLD was compared to the study group in terms of imaging features and post-ablative zone size dynamics at follow-up. Post-treatment scans of hepatic lesions treated with RFA and LTLD have distinctive imaging characteristics when compared to those treated with RFA alone. The addition of LTLD resulted in a regular or smooth enhancing rim on T1W MRI which often correlated with increased attenuation on CT. The LTLD-treated ablation zones were stable or enlarged at follow-up four weeks later in 69 % of study subjects as opposed to conventional RFA where the ablation zone underwent involution compared to imaging acquired immediately after the procedure. The imaging features following RFA with LTLD were different from those after standard RFA and can mimic residual or recurrent tumor. Knowledge of the subtle findings between the two groups can help avoid misinterpretation and proper identification of treatment failure in this setting. Increased size of the LTLD-treated ablation zone after RFA suggests the ongoing drug-induced biological effects.
    No preview · Article · Jul 2015 · CardioVascular and Interventional Radiology
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    ABSTRACT: To evaluate the effect of embolic diameter on achievement of hypoxia after embolization in an animal model of liver tumors. Inoculation of VX2 tumors in the left liver lobe was performed successfully in 12 New Zealand white rabbits weighing 3.7 kg ± 0.5 (mean ± SD). Tumors were deemed eligible for oxygen measurements when the maximum transverse diameter measured 15 mm or more by ultrasound examination. Direct monitoring of oxygenation of implanted rabbit hepatic VX2 tumors was performed with a fiberoptic electrode during and after transarterial embolization of the proper hepatic artery to angiographic flow stasis with microspheres measuring 70-150 μm, 100-300 μm, or 300-500 μm in diameter. Failure to achieve tumor hypoxia as defined despite angiographic flow stasis was observed in 10 of 11 animals. Embolization microsphere size effect failed to demonstrate a significant trend on hypoxia outcome among the diameters tested, and pair-wise comparisons of different embolic diameter treatment groups showed no difference in hypoxia outcome. All microsphere diameters tested resulted in similar absolute reduction (24.3 mm Hg ± 18.3, 29.1 mm Hg ± 1.8, and 19.9 mm Hg ± 9.3, P = .66) and percentage decrease in oxygen (56.0 mm Hg ± 23.9, 56.0 mm Hg ± 6.4, and 35.8 mm Hg ± 20.6, P = .65). Pair-wise comparisons for percent tumor area occupied by embolic agents showed a significantly reduced fraction for 300-500 μm diameters compared with 70-150 μm diameters (P < .05). In the rabbit VX2 liver tumor model, three tested microsphere diameters failed to cause tumor hypoxia as measured by a fiberoptic probe sensor according to the adopted hypoxia definitions. Copyright © 2015. Published by Elsevier Inc.
    No preview · Article · Jul 2015 · Journal of vascular and interventional radiology: JVIR

Publication Stats

7k Citations
1,048.76 Total Impact Points


  • 2002-2016
    • National Institutes of Health
      • • Branch of Urologic Oncology
      • • Center for Clinical Research
      • • Radiology and Imaging Sciences Department
      • • Branch of Surgery
      • • Center for Interventional Oncology
      베서스다, Maryland, United States
  • 2011-2015
    • NCI-Frederick
      Фредерик, Maryland, United States
  • 2004-2015
    • Georgetown University
      Washington, Washington, D.C., United States
    • Wayne State University
      • School of Medicine
      Detroit, Michigan, United States
  • 2001-2015
    • National Cancer Institute (USA)
      • • Molecular Imaging Program
      • • Center for Cancer Research
      • • Surgery Branch
      베서스다, Maryland, United States
  • 2013
    • Philips
      Eindhoven, North Brabant, Netherlands
  • 2010
    • National Eye Institute
      Maryland, United States
  • 2007
    • Northern Inyo Hospital
      BIH, California, United States
  • 2003
    • University of California, Davis
      Davis, California, United States
  • 2000-2002
    • Massachusetts General Hospital
      • Department of Radiology
      Boston, Massachusetts, United States
    • Harvard Medical School
      Boston, Massachusetts, United States
  • 1999-2002
    • Harvard University
      Cambridge, Massachusetts, United States