Technology in cancer research & treatment
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Technol. Cancer Res. Treat. · Aug 2012
Comparative StudyComparison of BOLD cerebrovascular reactivity mapping and DSC MR perfusion imaging for prediction of neurovascular uncoupling potential in brain tumors.
The coupling mechanism between neuronal firing and cerebrovascular dilatation can be significantly compromised in cerebral diseases, making it difficult to identify eloquent cortical areas near or within resectable lesions by using Blood Oxygen Level Dependent (BOLD) fMRI. Several metabolic and vascular factors have been considered to account for this lesion-induced neurovascular uncoupling (NVU), but no imaging gold standard exists currently for the detection of NVU. However, it is critical in clinical fMRI studies to evaluate the risk of NVU because the presence of NVU may result in false negative activation that may result in inadvertent resection of eloquent cortex, resulting in permanent postoperative neurologic deficits. ⋯ Our results demonstrate that while T2*MR perfusion maps and CVR maps are both adequate to map tumoral regions at risk of NVU in high grade gliomas, CVR maps can detect areas of decreased CVR also in low and intermediate grade gliomas where NVU may be caused by factors other than tumor neovascularity alone. Comparison of areas of abnormally decreased regional CVR with areas of absent BOLD task-based activation in expected eloquent cortical regions infiltrated by or adjacent to the tumors revealed overall 95% concordance, thus confirming the capability of BH CVR mapping to effectively demonstrate areas of NVU. ed by factors other than tumor neovascularity alone. Comparison of areas of abnormally decreased regional CVR with areas of absent BOLD task-based activation in expected eloquent cortical regions infiltrated by or adjacent to the tumors revealed overall 95% concordance, thus confirming the capability of BH CVR mapping to effectively demonstrate areas of NVU.
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Technol. Cancer Res. Treat. · Jun 2012
Cone beam CT (CBCT) evaluation of inter- and intra-fraction motion for patients undergoing brain radiotherapy immobilized using a commercial thermoplastic mask on a robotic couch.
Patients receiving fractionated intensity-modulated radiation therapy (IMRT) for brain tumors are often immobilized with a thermoplastic mask; however, masks do not perfectly re-orient the patient due to factors including the maximum pressure which can be applied to the face, deformations of the mask assembly, patient compliance, etc. Consequently, ~3-5mm PTV margins (beyond the CTV) are often recommended. We aimed to determine if smaller PTV margins are feasible using mask immobilization coupled with 1) a gantry mounted CBCT image guidance system and 2) position corrections provided by a full six-degree of freedom (6-DOF) robotic couch. ⋯ Robotic couch corrections reduced the 3D median error to 0.53 mm prior to treatment. Intra-fraction movement was responsible for increasing the median 3D positioning error to 0.86 mm, with 8% of fractions having a 3D positioning error greater than 2 mm. Clearly CBCT image guidance coupled with a robotic 6-DOF couch dramatically improved the positioning accuracy for patients immobilized in a thermoplastic mask system; however, such intra-fraction motion would be too large for single fraction radiosurgery.
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Technol. Cancer Res. Treat. · Apr 2012
Three-dimensional C-arm computed tomography combined with fluoroscopic guided pediculoplasty for treatment of vertebral body metastasis with lytic pedicle.
The aim of this retrospective study was to evaluate a percutaneous pediculoplasty (PP) technique, using 3-dimensional C-arm CT reformation combined with fluoroscopic guidance for patients presented vertebral body metastasis with lytic pedicle. Thirteen patients (average age 57.8 years) were treated through lytic pedicle approach in our study. ⋯ One patient died from underlying disease unrelated with the procedure at 5 month follow-up. PP through the lytic pedicle approach under 3-dimensional C-arm CT reformation combined with fluoroscopic guidance was a feasible, safe, and minimally invasive procedure that could provide both the precise control of needle placement and cement injection with one imaging system.
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Technol. Cancer Res. Treat. · Apr 2012
Prognostic value of 18F-FDG standard uptake value by integrated PET/CT in the staging of malignant pleural mesothelioma.
Malignant pleural mesothelioma (MPM) is a rare and aggressive tumor with generally disappointing results in terms of survival, however, there are occasional long-term survivors probably due to the biologic characteristics of the disease. Standard uptake value (SUV) of [(18)F] Fluorodeoxyglucose (FDG) evaluated by photon emission tomography (PET) is now widely accepted as an indicator of biologic behavior in several malignancies. The aim of this study was to verify whether SUV(max) and SUV(mean) are inversely associated with the prognosis of patients with MPM and whether there was a correlation between grading/disease stage and SUV value. ⋯ We observed a significant correlation only between high SUV(max) and high-grade disease. No other relationships between SUV(max) and SUV(mean) with biologic and clinical parameters were found. This is probably due to the patient characteristics and to the non-routine use of 18F-FDG PET/CT to stage rare tumors such as MPM.
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Technol. Cancer Res. Treat. · Feb 2012
Long term survival of mice with hepatocellular carcinoma after pulse power ablation with nanosecond pulsed electric fields.
Novel therapies are needed for treating hepatocellular carcinoma (HCC) without recurrence in a single procedure. In this work we evaluated anti-neoplastic effects of a pulse power ablation (PPA) with nanosecond pulsed electric fields (nsPEFs), a non-thermal, non-drug, local, regional method and investigated its molecular mechanisms for hepatocellular carcinoma tumor ablation in vivo. An ectopic tumor model was established using C57BL/6 mice with Hepa1-6 hepatocellular carcinoma cells. ⋯ NsPEF ablation eliminated hepatocellular carcinoma tumors by targeting two therapeutic sites, apoptosis induction and inhibition of angiogenesis, both important cancer hallmarks. These data indicate that PPA with nsPEFs is not limited to treating skin cancers and provide a rationale for continuing to investigate pulse power ablation for hepatocellular carcinoma using other models in pre-clinical applications and ultimately in clinical trials. Based on present treatments for specific HCC stages, it is anticipated that nsPEFs could be substituted for or used in combination with ablation therapies using heat, cold or chemicals.