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Fassi A, Schaerer J, Riboldi M, Sarrut D, Baroni G. An image-based method to synchronize cone-beam CT and optical surface tracking. J Appl Clin Med Phys 2015; 16:5152. [PMID: 26103183 PMCID: PMC5690086 DOI: 10.1120/jacmp.v16i2.5152] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 11/26/2014] [Accepted: 11/24/2014] [Indexed: 12/25/2022] Open
Abstract
The integration of in-room X-ray imaging and optical surface tracking has gained increasing importance in the field of image guided radiotherapy (IGRT). An essential step for this integration consists of temporally synchronizing the acquisition of X-ray projections and surface data. We present an image-based method for the synchronization of cone-beam computed tomography (CBCT) and optical surface systems, which does not require the use of additional hardware. The method is based on optically tracking the motion of a component of the CBCT/gantry unit, which rotates during the acquisition of the CBCT scan. A calibration procedure was implemented to relate the position of the rotating component identified by the optical system with the time elapsed since the beginning of the CBCT scan, thus obtaining the temporal correspondence between the acquisition of X-ray projections and surface data. The accuracy of the proposed synchronization method was evaluated on a motorized moving phantom, performing eight simultaneous acquisitions with an Elekta Synergy CBCT machine and the AlignRT optical device. The median time difference between the sinusoidal peaks of phantom motion signals extracted from the synchronized CBCT and AlignRT systems ranged between -3.1 and 12.9 msec, with a maximum interquartile range of 14.4 msec. The method was also applied to clinical data acquired from seven lung cancer patients, demonstrating the potential of the proposed approach in estimating the individual and daily variations in respiratory parameters and motion correlation of internal and external structures. The presented synchronization method can be particularly useful for tumor tracking applications in extracranial radiation treatments, especially in the field of patient-specific breathing models, based on the correlation between internal tumor motion and external surface surrogates.
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Dias MF, Riboldi M, Seco J, Castelhano I, Pella A, Mirandola A, Peralta L, Ciocca M, Orecchia R, Baroni G. Scan path optimization with/without clustering for active beam delivery in charged particle therapy. Phys Med 2015; 31:130-6. [DOI: 10.1016/j.ejmp.2015.01.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 01/02/2015] [Accepted: 01/03/2015] [Indexed: 12/29/2022] Open
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Altomare C, Guglielmann R, Riboldi M, Bellazzi R, Baroni G. Optimal marker placement in hadrontherapy: intelligent optimization strategies with augmented Lagrangian pattern search. J Biomed Inform 2015; 53:65-72. [PMID: 25220865 DOI: 10.1016/j.jbi.2014.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Revised: 08/25/2014] [Accepted: 09/02/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE In high precision photon radiotherapy and in hadrontherapy, it is crucial to minimize the occurrence of geometrical deviations with respect to the treatment plan in each treatment session. To this end, point-based infrared (IR) optical tracking for patient set-up quality assessment is performed. Such tracking depends on external fiducial points placement. The main purpose of our work is to propose a new algorithm based on simulated annealing and augmented Lagrangian pattern search (SAPS), which is able to take into account prior knowledge, such as spatial constraints, during the optimization process. MATERIAL AND METHODS The SAPS algorithm was tested on data related to head and neck and pelvic cancer patients, and that were fitted with external surface markers for IR optical tracking applied for patient set-up preliminary correction. The integrated algorithm was tested considering optimality measures obtained with Computed Tomography (CT) images (i.e. the ratio between the so-called target registration error and fiducial registration error, TRE/FRE) and assessing the marker spatial distribution. Comparison has been performed with randomly selected marker configuration and with the GETS algorithm (Genetic Evolutionary Taboo Search), also taking into account the presence of organs at risk. RESULTS The results obtained with SAPS highlight improvements with respect to the other approaches: (i) TRE/FRE ratio decreases; (ii) marker distribution satisfies both marker visibility and spatial constraints. We have also investigated how the TRE/FRE ratio is influenced by the number of markers, obtaining significant TRE/FRE reduction with respect to the random configurations, when a high number of markers is used. CONCLUSIONS The SAPS algorithm is a valuable strategy for fiducial configuration optimization in IR optical tracking applied for patient set-up error detection and correction in radiation therapy, showing that taking into account prior knowledge is valuable in this optimization process. Further work will be focused on the computational optimization of the SAPS algorithm toward fast point-of-care applications.
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Fattori G, Riboldi M, Pella A, Peroni M, Cerveri P, Desplanques M, Fontana G, Tagaste B, Valvo F, Orecchia R, Baroni G. Image guided particle therapy in CNAO room 2: Implementation and clinical validation. Phys Med 2015; 31:9-15. [DOI: 10.1016/j.ejmp.2014.10.075] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 10/10/2014] [Accepted: 10/11/2014] [Indexed: 01/24/2023] Open
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Belfatto A, Riboldi M, Ciardo D, Cattani F, Cecconi A, Lazzari R, Jereczek-Fossa BA, Orecchia R, Baroni G, Cerveri P. Modeling the Interplay Between Tumor Volume Regression and Oxygenation in Uterine Cervical Cancer During Radiotherapy Treatment. IEEE J Biomed Health Inform 2015; 20:596-605. [PMID: 25647734 DOI: 10.1109/jbhi.2015.2398512] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This paper describes a patient-specific mathematical model to predict the evolution of uterine cervical tumors at a macroscopic scale, during fractionated external radiotherapy. The model provides estimates of tumor regrowth and dead-cell reabsorption, incorporating the interplay between tumor regression rate and radiosensitivity, as a function of the tumor oxygenation level. Model parameters were estimated by minimizing the difference between predicted and measured tumor volumes, these latter being obtained from a set of 154 serial cone-beam computed tomography scans acquired on 16 patients along the course of the therapy. The model stratified patients according to two different estimated dynamics of dead-cell removal and to the predicted initial value of the tumor oxygenation. The comparison with a simpler model demonstrated an improvement in fitting properties of this approach (fitting error average value <5%, p < 0.01), especially in case of tumor late responses, which can hardly be handled by models entailing a constant radiosensitivity, failing to model changes from initial severe hypoxia to aerobic conditions during the treatment course. The model predictive capabilities suggest the need of clustering patients accounting for cancer cell line, tumor staging, as well as microenvironment conditions (e.g., oxygenation level).
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156
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Fassi A, Seregni M, Riboldi M, Cerveri P, Sarrut D, Ivaldi GB, de Fatis PT, Liotta M, Baroni G. Surrogate-driven deformable motion model for organ motion tracking in particle radiation therapy. Phys Med Biol 2015; 60:1565-82. [DOI: 10.1088/0031-9155/60/4/1565] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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157
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Molteni R, Bianchi E, Patete P, Fabbri M, Baroni G, Dubini G, Pardi R. A novel device to concurrently assess leukocyte extravasation and interstitial migration within a defined 3D environment. LAB ON A CHIP 2015; 15:195-207. [PMID: 25337693 DOI: 10.1039/c4lc00741g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Leukocyte extravasation and interstitial migration are key events during inflammation. Traditional in vitro techniques address only specific steps of cell recruitment to tissues and fail to recapitulate the whole process in an appropriate three-dimensional (3D) microenvironment. Herein, we describe a device that enables us to qualitatively and quantitatively assess in 4D the interdependent steps underlying leukocyte trafficking in a close-to-physiology in vitro context. Real-time tracking of cells, from initial adhesion to the endothelium and subsequent diapedesis to interstitial migration towards the source of the chemoattractant within the 3D collagen matrix, is enabled by the use of optically transparent porous membranes laid over the matrix. Unique features of the device, such as the use of non-planar surfaces and the contribution of physiological flow to the establishment of a persistent chemoattractant gradient, were assessed by numerical simulations and validated by proof-of-concept, simultaneous testing of differentially treated primary mouse neutrophils. This microfluidic platform offers new and versatile tools to thoroughly investigate the stepwise process of circulating cell recruitment to target tissues in vitro and to test novel therapeutics targeting various steps of the process.
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Landry G, Dedes G, Zöllner C, Handrack J, Janssens G, Orban de Xivry J, Reiner M, Paganelli C, Riboldi M, Kamp F, Söhn M, Wilkens JJ, Baroni G, Belka C, Parodi K. Phantom based evaluation of CT to CBCT image registration for proton therapy dose recalculation. Phys Med Biol 2014; 60:595-613. [PMID: 25548912 DOI: 10.1088/0031-9155/60/2/595] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The ability to perform dose recalculation on the anatomy of the day is important in the context of adaptive proton therapy. The objective of this study was to investigate the use of deformable image registration (DIR) and cone beam CT (CBCT) imaging to generate the daily stopping power distribution of the patient. We investigated the deformation of the planning CT scan (pCT) onto daily CBCT images to generate a virtual CT (vCT) using a deformable phantom designed for the head and neck (H & N) region. The phantom was imaged at a planning CT scanner in planning configuration, yielding a pCT and in deformed, treatment day configuration, yielding a reference CT (refCT). The treatment day configuration was additionally scanned at a CBCT scanner. A Morphons DIR algorithm was used to generate a vCT. The accuracy of the vCT was evaluated by comparison to the refCT in terms of corresponding features as identified by an adaptive scale invariant feature transform (aSIFT) algorithm. Additionally, the vCT CT numbers were compared to those of the refCT using both profiles and regions of interest and the volumes and overlap (DICE coefficients) of various phantom structures were compared. The water equivalent thickness (WET) of the vCT, refCT and pCT were also compared to evaluate proton range differences. Proton dose distributions from the same initial fluence were calculated on the refCT, vCT and pCT and compared in terms of proton range. The method was tested on a clinical dataset using a replanning CT scan acquired close in time to a CBCT scan as reference using the WET evaluation. Results from the aSIFT investigation suggest a deformation accuracy of 2-3 mm. The use of the Morphon algorithm did not distort CT number intensity in uniform regions and WET differences between vCT and refCT were of the order of 2% of the proton range. This result was confirmed by proton dose calculations. The patient results were consistent with phantom observations. In conclusion, our phantom study suggests the vCT approach is adequate for proton dose recalculation on the basis of CBCT imaging.
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Peroni M, Golland P, Sharp GC, Baroni G. Stopping Criteria for Log-Domain Diffeomorphic Demons Registration: An Experimental Survey for Radiotherapy Application. Technol Cancer Res Treat 2014; 15:77-90. [PMID: 24000996 DOI: 10.7785/tcrtexpress.2013.600269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 06/26/2013] [Indexed: 11/06/2022] Open
Abstract
A crucial issue in deformable image registration is achieving a robust registration algorithm at a reasonable computational cost. Given the iterative nature of the optimization procedure an algorithm must automatically detect convergence, and stop the iterative process when most appropriate. This paper ranks the performances of three stopping criteria and six stopping value computation strategies for a Log-Domain Demons Deformable registration method simulating both a coarse and a fine registration. The analyzed stopping criteria are: (a) velocity field update magnitude, (b) mean squared error, and (c) harmonic energy. Each stoping condition is formulated so that the user defines a threshold ∊, which quantifies the residual error that is acceptable for the particular problem and calculation strategy. In this work, we did not aim at assigning a value to e, but to give insights in how to evaluate and to set the threshold on a given exit strategy in a very popular registration scheme. Experiments on phantom and patient data demonstrate that comparing the optimization metric minimum over the most recent three iterations with the minimum over the fourth to sixth most recent iterations can be an appropriate algorithm stopping strategy. The harmonic energy was found to provide best trade-off between robustness and speed of convergence for the analyzed registration method at coarse registration, but was outperformed by mean squared error when all the original pixel information is used. This suggests the need of developing mathematically sound new convergence criteria in which both image and vector field information could be used to detect the actual convergence, which could be especially useful when considering multi-resolution registrations. Further work should be also dedicated to study same strategies performances in other deformable registration methods and body districts.
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Gianoli C, Riboldi M, Fontana G, Giri MG, Grigolato D, Ferdeghini M, Cavedon C, Baroni G. Optimized PET Imaging for 4D Treatment Planning in Radiotherapy: the Virtual 4D PET Strategy. Technol Cancer Res Treat 2014; 14:99-110. [DOI: 10.7785/tcrt.2012.500393] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The purpose of the study is to evaluate the performance of a novel strategy, referred to as “virtual 4D PET”, aiming at the optimization of hybrid 4D CT-PET scan for radiotherapy treatment planning. The virtual 4D PET strategy applies 4D CT motion modeling to avoid time-resolved PET image acquisition. This leads to a reduction of radioactive tracer administered to the patient and to a total acquisition time comparable to free-breathing PET studies. The proposed method exploits a motion model derived from 4D CT, which is applied to the free-breathing PET to recover respiratory motion and motion blur. The free-breathing PET is warped according to the motion model, in order to generate the virtual 4D PET. The virtual 4D PET strategy was tested on images obtained from a 4D computational anthropomorphic phantom. The performance was compared to conventional motion compensated 4D PET. Tests were also carried out on clinical 4D CT-PET scans coming from seven lung and liver cancer patients. The virtual 4D PET strategy was able to recover lesion motion, with comparable performance with respect to the motion compensated 4D PET. The compensation of the activity blurring due to motion was successfully achieved in terms of spill out removal. Specific limitations were highlighted in terms of partial volume compensation. Results on clinical 4D CT-PET scans confirmed the efficacy in 4D PET count statistics optimization, as equal to the free-breathing PET, and recovery of lesion motion. Compared to conventional motion compensation strategies that explicitly require 4D PET imaging, the virtual 4D PET strategy reduces clinical workload and computational costs, resulting in significant advantages for radiotherapy treatment planning.
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Bert C, Graeff C, Riboldi M, Nill S, Baroni G, Knopf AC. Advances in 4D treatment planning for scanned particle beam therapy - report of dedicated workshops. Technol Cancer Res Treat 2014; 13:485-95. [PMID: 24354749 PMCID: PMC4527425 DOI: 10.7785/tcrtexpress.2013.600274] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 09/27/2013] [Accepted: 10/01/2013] [Indexed: 11/25/2022] Open
Abstract
We report on recent progress in the field of mobile tumor treatment with scanned particle beams, as discussed in the latest editions of the 4D treatment planning workshop. The workshop series started in 2009, with about 20 people from 4 research institutes involved, all actively working on particle therapy delivery and development. The first workshop resulted in a summary of recommendations for the treatment of mobile targets, along with a list of requirements to apply these guidelines clinically. The increased interest in the treatment of mobile tumors led to a continuously growing number of attendees: the 2012 edition counted more than 60 participants from 20 institutions and commercial vendors. The focus of research discussions among workshop participants progressively moved from 4D treatment planning to complete 4D treatments, aiming at effective and safe treatment delivery. Current research perspectives on 4D treatments include all critical aspects of time resolved delivery, such as in-room imaging, motion detection, beam application, and quality assurance techniques. This was motivated by the start of first clinical treatments of hepato cellular tumors with a scanned particle beam, relying on gating or abdominal compression for motion mitigation. Up to date research activities emphasize significant efforts in investigating advanced motion mitigation techniques, with a specific interest in the development of dedicated tools for experimental validation. Potential improvements will be made possible in the near future through 4D optimized treatment plans that require upgrades of the currently established therapy control systems for time resolved delivery. But since also these novel optimization techniques rely on the validity of the 4DCT, research focusing on alternative 4D imaging technique, such as MRI based 4DCT generation will continue.
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Bianchi S, Caini S, Paglierani M, Saieva C, Vezzosi V, Baroni G, Simoni A, Palli D. Accuracy and Reproducibility of HER2 Status in Breast Cancer Using Immunohistochemistry: A Quality Control Study in Tuscany Evaluating the Impact of Updated 2013 ASCO/CAP Recommendations. Pathol Oncol Res 2014; 21:477-85. [PMID: 25367072 DOI: 10.1007/s12253-014-9852-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 10/14/2014] [Indexed: 01/12/2023]
Abstract
The correct identification of HER2-positive cases is a key point to provide the most appropriate therapy to breast cancer (BC) patients. We aimed at investigating the reproducibility and accuracy of HER2 expression by immunohistochemistry (IHC) in a selected series of 35 invasive BC cases across the pathological anatomy laboratories in Tuscany, Italy. Unstained sections of each BC case were sent to 12 participating laboratories. Pathologists were required to score according to the Food and Drug Administration (FDA) four-tier scoring system (0, 1+, 2+, 3+). Sixteen and nineteen cases were HER2 non-amplified and amplified respectively on fluorescence in situ hybridization. Among 192 readings of the 16 HER2 non-amplified samples, 153 (79.7%) were coded as 0 or 1+, 39 (20.3%) were 2+, and none was 3+ (false positive rate 0%). Among 228 readings of the 19 HER2 amplified samples, 56 (24.6%) were scored 0 or 1+, 79 (34.6%) were 2+, and 93 (40.8%) were 3+. The average sensitivity was 75.4%, ranging between 47% and 100%, and the overall false negative rate was 24.6%. Participation of pathological anatomy laboratories performing HER2 testing by IHC in external quality assurance programs should be made mandatory, as the system is able to identify laboratories with suboptimal performance that may need technical advice. Updated 2013 ASCO/CAP recommendations should be adopted as the widening of IHC 2+ "equivocal" category would improve overall accuracy of HER2 testing, as more cases would be classified in this category and, consequently, tested with an in situ hybridisation method.
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Gianoli C, Bauer J, Riboldi M, De Bernardi E, Fattori G, Baselli G, Debus J, Parodi K, Baroni G. Regional MLEM reconstruction strategy for PET-based treatment verification in ion beam radiotherapy. Phys Med Biol 2014; 59:6979-95. [DOI: 10.1088/0031-9155/59/22/6979] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Jereczek-Fossa BA, Piperno G, Ronchi S, Catalano G, Fodor C, Cambria R, Fossati Ing P, Gherardi F, Alterio D, Zerini D, Garibaldi C, Baroni G, De Cobelli O, Orecchia R. Linac-based stereotactic body radiotherapy for oligometastatic patients with single abdominal lymph node recurrent cancer. Am J Clin Oncol 2014; 37:227-33. [PMID: 22992626 DOI: 10.1097/coc.0b013e3182610878] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVES To evaluate stereotactic body radiotherapy (SBRT) for single abdominal lymph node cancer recurrence. METHODS Inclusion criteria for this retrospective study were as follows: adult oligometastatic cancer patients with single abdominal lymph node recurrence that underwent SBRT but not other local therapy, written informed consent for treatment. Previous radiotherapy or concomitant systemic therapy were allowed. Toxicity and tumor response were evaluated using Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Scale and Response Evaluation Criteria in Solid Tumors. RESULTS Sixty-nine patients (94 lesions) underwent SBRT (median 24 Gy/3 fractions). Primary diagnosis included urological, gastrointestinal, gynecologic, and other malignancies. Concomitant systemic therapy was performed in 35 cases. Median follow-up was 20 months. Two grade 3 acute and 1 grade 4 late toxicity events were registered. Complete radiologic response, partial response, stabilization, and progressive disease were observed in 36 (44%), 21 (26%), 20 (25%), and 4 (5%) lesions, respectively, out of 81 evaluable lesions. Response rates were similar when analysis was restricted to lesions treated with exclusive SBRT (no concomitant therapy). Actuarial 3-year in-field progression-free interval, progression-free survival and overall-survival rates were 64.3%, 11.7%, and 49.9%, respectively. Overall-survival rates were significantly higher in favorable histology cases (prostate and kidney tumors). Pattern of failure was predominantly out-field. CONCLUSIONS SBRT is a feasible approach for single abdominal lymph node recurrence, offering excellent in-field tumor control with low-toxicity profile. Future studies are warranted to identify the patients that benefit most from this treatment. The optimal combination with systemic treatment should also be defined.
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Conti V, Pantaleo M, Barba C, Baroni G, Mei D, Buccoliero AM, Giglio S, Giordano F, Baek ST, Gleeson JG, Guerrini R. Focal dysplasia of the cerebral cortex and infantile spasms associated with somatic 1q21.1-q44 duplication including the AKT3 gene. Clin Genet 2014; 88:241-7. [PMID: 25091978 DOI: 10.1111/cge.12476] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/15/2014] [Accepted: 07/30/2014] [Indexed: 02/01/2023]
Abstract
Somatic and germline duplications or activating mutations of AKT3 have been reported in patients with hemimegalencephaly and megalencephaly. We performed array comparative genomic hybridization on brain tissue and blood in 16 consecutive patients with symptomatic epilepsy due to focal or multilobar malformations of cortical development who underwent surgical treatment of epilepsy. One patient with infantile spasms and a dysplastic left frontal lobe harboured a somatic trisomy of the 1q21.1-q44 chromosomal region, encompassing the AKT3 gene, in the dysplastic brain tissue but not in blood and saliva. Histopathology revealed severe cortical dyslamination, a thin cortex in the premotor area with microgyri and microsulci, immature neurons with disoriented dendrites and areas of cortical heterotopia in the sub-cortical white matter. These cytoarchitectural changes are close to those defining type Ib focal cortical dysplasia. Immunohistochemistry in brain specimens showed hyperactivation of the PI3K/AKT/mTOR pathway. These findings indicate that AKT3 upregulation may cause focal malformations of cortical development. There appears to be an etiologic continuum between hemimegalencephaly and focal cortical dysplastic lesions. The extent of brain malformations due to AKT3 upregulation may be related to the embryonic stage when the post-zygotic gene alteration occurs.
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Fattori G, Riboldi M, Scifoni E, Krämer M, Pella A, Durante M, Ronchi S, Bonora M, Orecchia R, Baroni G. Dosimetric effects of residual uncertainties in carbon ion treatment of head chordoma. Radiother Oncol 2014; 113:66-71. [DOI: 10.1016/j.radonc.2014.08.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 07/19/2014] [Accepted: 08/02/2014] [Indexed: 01/03/2023]
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Pennati F, Salito C, Baroni G, Woods J, Aliverti A. Comparison between multivolume CT-based surrogates of regional ventilation in healthy subjects. Acad Radiol 2014; 21:1268-75. [PMID: 25126974 DOI: 10.1016/j.acra.2014.05.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 05/22/2014] [Accepted: 05/27/2014] [Indexed: 01/14/2023]
Abstract
RATIONALE AND OBJECTIVES The assessment of regional ventilation is of critical importance when investigating lung function during disease progression and planning of pulmonary interventions. Recently, different computed tomography (CT)-based parameters have been proposed as surrogates of lung ventilation. The aim of the present study was to compare these parameters, namely variations of density (ΔHU), specific volume (sVol), and specific gas volume (ΔSVg) between different lung volumes, in relation to their topographic distribution within the lung. MATERIALS AND METHODS Ten healthy volunteers were scanned via high-resolution CT at residual volume (RV) and total lung capacity (TLC); ΔHU, sVol, and ΔSVg were mapped voxel by voxel after registering TLC onto RV. Variations of the three parameters along the vertical and horizontal directions were analyzed. RESULTS Along the vertical direction (from ventral to dorsal regions), a strong dependence on gravity was found in ΔHU and sVol, with greater values in the dorsal regions of the lung (P < .001), whereas ΔSVg was more homogeneously distributed within the lung. Conversely, along the caudocranial direction (from lung bases to apexes) where no gravitational gradient is present, the three parameters behaved similarly, with lower values at the apices. CONCLUSIONS ΔHU, sVol, and ΔSVg behave differently along the gravity direction. As the greater amount of air delivered to the dependent portion of the lung supplies a larger number of alveoli, the amount of gas delivered to alveoli compared to the mass of tissue is not gravity dependent. The minimization of gravity dependence in the distribution of ventilation when using ΔSVg suggests that this parameter is more reliable to discriminate healthy from pathologic regions.
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Cerveri P, Manzotti A, Confalonieri N, Baroni G. Automating the design of resection guides specific to patient anatomy in knee replacement surgery by enhanced 3D curvature and surface modeling of distal femur shape models. Comput Med Imaging Graph 2014; 38:664-74. [PMID: 25262320 DOI: 10.1016/j.compmedimag.2014.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 08/25/2014] [Accepted: 09/03/2014] [Indexed: 10/24/2022]
Abstract
Personalized resection guides (PRG) have been recently proposed in the domain of knee replacement, demonstrating clinical outcome similar or even superior to both manual and navigated interventions. Among the mandatory pre-surgical steps for PRG prototyping, the measurement of clinical landmarks (CL) on the bony surfaces is recognized as a key issue due to lack of standardized methodologies, operator-dependent variability and time expenditure. In this paper, we focus on the reliability and repeatability of an anterior-posterior axis, also known as Whiteside line (WL), of the distal femur proposing automatic surface processing and modeling methods aimed at overcoming some of the major concerns related to the manual identification of such CL on 2D images and 3D models. We show that the measurement of WL, exploiting the principle of mean-shifting surface curvature, is highly repeatable and coherent with clinical knowledge.
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Massi D, Brusa D, Merelli B, Ciano M, Audrito V, Serra S, Buonincontri R, Baroni G, Nassini R, Minocci D, Cattaneo L, Tamborini E, Carobbio A, Rulli E, Deaglio S, Mandalà M. PD-L1 marks a subset of melanomas with a shorter overall survival and distinct genetic and morphological characteristics. Ann Oncol 2014; 25:2433-2442. [PMID: 25223485 DOI: 10.1093/annonc/mdu452] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Programmed cell death ligand 1 (PD-L1) is a cell surface molecule that plays a critical role in suppressing immune responses, mainly through binding of the PD-1 receptor on T lymphocytes. PD-L1 may be expressed by metastatic melanoma (MM). However, its clinical and biological significance remains unclear. Here, we investigated whether expression of PD-L1 in MM identifies a biologically more aggressive form of the disease, carrying prognostic relevance. PATIENTS AND METHODS PD-L1 expression was analyzed by immunohistochemistry using two different antibodies in primary tumors and paired metastases from 81 melanoma patients treated at a single institution. Protein expression levels were correlated with PD-L1 mRNA, BRAF mutational status and clinical outcome. PD-L1(+) and PD-L1(-) subsets of the A375 cell line were stabilized in vitro and compared using gene expression profiling and functional assays. Results were confirmed using xenograft models. RESULTS PD-L1 membrane positivity was detected in 30/81 (37%) of patients. By multivariate analysis, Breslow thickness and PD-L1 membrane positivity were independent risk factors for melanoma-specific death {PD-L1 5% cutoff [hazard ratio (HR) 3.92, confidence interval (CI) 95% 1.61-9.55 P < 0.003], PD-L1 as continuous variable (HR 1.03, 95% CI 1.02-1.04 P < 0.002)}. PD-L1 expression defined a subset of the BRAF-mutated A375 cell line characterized by a highly invasive phenotype and by enhanced ability to grow in xenograft models. CONCLUSIONS PD-L1 is an independent prognostic marker in melanoma. If confirmed, our clinical and experimental data suggest that PD-L1(+) melanomas should be considered a disease subset with distinct genetic and morpho-phenotypic features, leading to enhanced aggressiveness and invasiveness.
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Mancosu P, Baroni G, Alongi F, Esposito L, Stasi M, Strigari L. Crowd knowledge based community in radiotherapy: In response to Yartev et al. Radiother Oncol 2014; 112:453. [DOI: 10.1016/j.radonc.2014.02.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 02/20/2014] [Indexed: 10/25/2022]
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Knopf A, Nill S, Yohannes I, Graeff C, Dowdell S, Kurz C, Sonke JJ, Biegun AK, Lang S, McClelland J, Champion B, Fast M, Wölfelschneider J, Gianoli C, Rucinski A, Baroni G, Richter C, van de Water S, Grassberger C, Weber D, Poulsen P, Shimizu S, Bert C. Challenges of radiotherapy: report on the 4D treatment planning workshop 2013. Phys Med 2014; 30:809-15. [PMID: 25172392 DOI: 10.1016/j.ejmp.2014.07.341] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 07/23/2014] [Accepted: 07/28/2014] [Indexed: 01/27/2023] Open
Abstract
This report, compiled by experts on the treatment of mobile targets with advanced radiotherapy, summarizes the main conclusions and innovations achieved during the 4D treatment planning workshop 2013. This annual workshop focuses on research aiming to advance 4D radiotherapy treatments, including all critical aspects of time resolved delivery, such as in-room imaging, motion detection, motion managing, beam application, and quality assurance techniques. The report aims to revise achievements in the field and to discuss remaining challenges and potential solutions. As main achievements advances in the development of a standardized 4D phantom and in the area of 4D-treatment plan optimization were identified. Furthermore, it was noticed that MR imaging gains importance and high interest for sequential 4DCT/MR data sets was expressed, which represents a general trend of the field towards data covering a longer time period of motion. A new point of attention was work related to dose reconstructions, which may play a major role in verification of 4D treatment deliveries. The experimental validation of results achieved by 4D treatment planning and the systematic evaluation of different deformable image registration methods especially for inter-modality fusions were identified as major remaining challenges. A challenge that was also suggested as focus for future 4D workshops was the adaptation of image guidance approaches from conventional radiotherapy into particle therapy. Besides summarizing the last workshop, the authors also want to point out new evolving demands and give an outlook on the focus of the next workshop.
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Spadea MF, Verburg JM, Baroni G, Seco J. The impact of low-Z and high-Z metal implants in IMRT: a Monte Carlo study of dose inaccuracies in commercial dose algorithms. Med Phys 2014; 41:011702. [PMID: 24387494 DOI: 10.1118/1.4829505] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The aim of the study was to evaluate the dosimetric impact of low-Z and high-Z metallic implants on IMRT plans. METHODS Computed tomography (CT) scans of three patients were analyzed to study effects due to the presence of Titanium (low-Z), Platinum and Gold (high-Z) inserts. To eliminate artifacts in CT images, a sinogram-based metal artifact reduction algorithm was applied. IMRT dose calculations were performed on both the uncorrected and corrected images using a commercial planning system (convolution/superposition algorithm) and an in-house Monte Carlo platform. Dose differences between uncorrected and corrected datasets were computed and analyzed using gamma index (Pγ<1) and setting 2 mm and 2% as distance to agreement and dose difference criteria, respectively. Beam specific depth dose profiles across the metal were also examined. RESULTS Dose discrepancies between corrected and uncorrected datasets were not significant for low-Z material. High-Z materials caused under-dosage of 20%-25% in the region surrounding the metal and over dosage of 10%-15% downstream of the hardware. Gamma index test yielded Pγ<1>99% for all low-Z cases; while for high-Z cases it returned 91% < Pγ<1< 99%. Analysis of the depth dose curve of a single beam for low-Z cases revealed that, although the dose attenuation is altered inside the metal, it does not differ downstream of the insert. However, for high-Z metal implants the dose is increased up to 10%-12% around the insert. In addition, Monte Carlo method was more sensitive to the presence of metal inserts than superposition/convolution algorithm. CONCLUSIONS The reduction in terms of dose of metal artifacts in CT images is relevant for high-Z implants. In this case, dose distribution should be calculated using Monte Carlo algorithms, given their superior accuracy in dose modeling in and around the metal. In addition, the knowledge of the composition of metal inserts improves the accuracy of the Monte Carlo dose calculation significantly.
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Pella A, Riboldi M, Tagaste B, Bianculli D, Desplanques M, Fontana G, Cerveri P, Seregni M, Fattori G, Orecchia R, Baroni G. Commissioning and Quality Assurance of an Integrated System for Patient Positioning and Setup Verification in Particle Therapy. Technol Cancer Res Treat 2014; 13:303-14. [DOI: 10.7785/tcrt.2012.500386] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In an increasing number of clinical indications, radiotherapy with accelerated particles shows relevant advantages when compared with high energy X-ray irradiation. However, due to the finite range of ions, particle therapy can be severely compromised by setup errors and geometric uncertainties. The purpose of this work is to describe the commissioning and the design of the quality assurance procedures for patient positioning and setup verification systems at the Italian National Center for Oncological Hadrontherapy (CNAO). The accuracy of systems installed in CNAO and devoted to patient positioning and setup verification have been assessed using a laser tracking device. The accuracy in calibration and image based setup verification relying on in room X-ray imaging system was also quantified. Quality assurance tests to check the integration among all patient setup systems were designed, and records of daily QA tests since the start of clinical operation (2011) are presented. The overall accuracy of the patient positioning system and the patient verification system motion was proved to be below 0.5 mm under all the examined conditions, with median values below the 0.3 mm threshold. Image based registration in phantom studies exhibited sub-millimetric accuracy in setup verification at both cranial and extra-cranial sites. The calibration residuals of the OTS were found consistent with the expectations, with peak values below 0.3 mm. Quality assurance tests, daily performed before clinical operation, confirm adequate integration and sub-millimetric setup accuracy. Robotic patient positioning was successfully integrated with optical tracking and stereoscopic X-ray verification for patient setup in particle therapy. Sub-millimetric setup accuracy was achieved and consistently verified in daily clinical operation.
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Fassi A, Ivaldi GB, Meaglia I, Porcu P, de Fatis PT, Liotta M, Riboldi M, Baroni G. Response to: Reproducibility of the external surface position in left-breast DIBH radiotherapy with spirometer-based monitoring: methodological mistake. J Appl Clin Med Phys 2014; 15:401. [PMID: 25207425 PMCID: PMC5875500 DOI: 10.1120/jacmp.v15i4.4954] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 03/04/2014] [Indexed: 12/04/2022] Open
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Gianoli C, Riboldi M, Kurz C, De Bernardi E, Bauer J, Fontana G, Ciocca M, Parodi K, Baroni G. PET-CT scanner characterization for PET raw data use in biomedical research. Comput Med Imaging Graph 2014; 38:358-68. [DOI: 10.1016/j.compmedimag.2014.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 03/11/2014] [Accepted: 03/24/2014] [Indexed: 11/27/2022]
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