Publications by authors named "Giacomo Feliciani"

9 Publications

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Exploratory Analysis of F-3'-deoxy-3'-fluorothymidine (F-FLT) PET/CT-Based Radiomics for the Early Evaluation of Response to Neoadjuvant Chemotherapy in Patients With Locally Advanced Breast Cancer.

Front Oncol 2021 24;11:601053. Epub 2021 Jun 24.

Nuclear Medicine Unit, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) "Dino Amadori," Meldola, Italy.

Purpose: The objective of this study was to evaluate a set of radiomics-based advanced textural features extracted from F-FLT-PET/CT images to predict tumor response to neoadjuvant chemotherapy (NCT) in patients with locally advanced breast cancer (BC).

Materials And Methods: Patients with operable (T2-T3, N0-N2, M0) or locally advanced (T4, N0-N2, M0) BC were enrolled. All patients underwent chemotherapy (six cycles every 3 weeks). Surgery was performed within 4 weeks of the end of NCT. The MD Anderson Residual Cancer Burden calculator was used to evaluate the pathological response. F-FLT-PET/CT was performed 2 weeks before the start of NCT and approximately 3 weeks after the first cycle. The evaluation of PET response was based on EORTC criteria. Standard uptake value (SUV) statistics (SUV, SUV, SUV), together with 148 textural features, were extracted from each lesion. Indices that are robust against contour variability (ICC test) were used as independent variables to logistically model tumor response. LASSO analysis was used for variable selection.

Results: Twenty patients were included in the study. Lesions from 15 patients were evaluable and analyzed: 9 with pathological complete response (pCR) and 6 with pathological partial response (pPR). Concordance between PET response and histological examination was found in 13/15 patients. LASSO logistic modelling identified a combination of SUV and the textural feature index IVH_VolumeIntFract_90 as the most useful to classify PET response, and a combination of PET response, ID range, and ID_Coefficient of Variation as the most useful to classify pathological response.

Conclusions: Our study suggests the potential usefulness of FLT-PET for early monitoring of response to NCT. A model based on PET radiomic characteristics could have good discriminatory capacity of early response before the end of treatment.
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http://dx.doi.org/10.3389/fonc.2021.601053DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8264651PMC
June 2021

The potential role of MR based radiomic biomarkers in the characterization of focal testicular lesions.

Sci Rep 2021 Feb 10;11(1):3456. Epub 2021 Feb 10.

Department of Morphology Surgery and Experimental Medicine, University of Ferrara, Via L. Ariosto 34, 44121, Ferrara, Italy.

How to differentiate with MRI-based techniques testicular germ (TGCTs) and testicular non-germ cell tumors (TNGCTs) is still under debate and Radiomics may be the turning key. Our purpose is to investigate the performance of MRI-based Radiomics signatures for the preoperative prediction of testicular neoplasm histology. The aim is twofold: (i), differentiating TGCTs and TNGCTs status and (ii) differentiating seminomas (SGCTs) from non-seminomatous (NSGCTs). Forty-two patients with pathology-proven testicular neoplasms and referred for pre-treatment MRI, were retrospectively enrolled. Thirty-two out of 44 lesions were TGCTs. Twelve out of 44 were TNGCTs or other histologies. Two radiologists segmented the volume of interest on T2-weighted images. Approximately 500 imaging features were extracted. Least Absolute Shrinkage and Selection Operator (LASSO) was applied as method for variable selection. A linear model and a linear support vector machine (SVM) were trained with selected features to assess discrimination scores for the two endpoints. LASSO identified 3 features that were employed to build fivefold validated linear discriminant and linear SVM classifiers for the TGCT-TNGCT endpoint giving an overall accuracy of 89%. Four features were employed to build another SVM for the SGCT-SNGCT endpoint with an overall accuracy of 86%. The data obtained proved that T2-weighted-based Radiomics is a promising tool in the diagnostic workup of testicular neoplasms by discriminating germ cell from non-gem cell tumors, and seminomas from non-seminomas.
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http://dx.doi.org/10.1038/s41598-021-83023-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7875983PMC
February 2021

Radiation protection and dosimetry issues for patients with prostate cancer after I-125 low-dose-rate brachytherapy permanent implant.

Brachytherapy 2021 Jan-Feb;20(1):272-278. Epub 2020 Oct 9.

Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola FC, Italy.

Purpose: The aim of this work was to analyze the exposure rates measured in the proximity of patients who underwent prostate low-dose-rate brachytherapy with I-125 implant. Effective doses to relatives and to population were computed to estimate the time to reach radioprotection dose constraints.

Methods And Materials: Measurements were obtained from 180 patients, whereas the body mass index was calculated and reported for 77 patients. The day after the implant, K˙ measurements were conducted at various skin distances and positions and converted to effective doses. A theoretical model was developed to estimate effective doses from total implanted activity. The latter was approximated with a 10-mL vial inside the patient.

Results: The K˙ measurements showed a low correlation with the total implanted activity, albeit an increasing trend of K˙ was observed on increasing the activity. A stronger correlation was found between body mass index and K˙ measurements. The effective dose to population is in general lower than dose constraints as well as the effective doses to relatives, with the exception of children and pregnant women, who command special precautions. We report differences between the experimental model- and theoretical model-based dose evaluation together with their comparison with previous studies found in literature.

Conclusions: Based on the K˙ measurements and the results of the present analysis, it is possible to provide the patient with radiation safety instructions specifically tailored to his relatives' habits and working environment.
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http://dx.doi.org/10.1016/j.brachy.2020.09.003DOI Listing
October 2020

Clinical evidence of abscopal effect in cutaneous squamous cell carcinoma treated with diffusing alpha emitters radiation therapy: a case report.

J Contemp Brachytherapy 2019 Oct 30;11(5):449-457. Epub 2019 Oct 30.

Skin Cancer Unit, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola (FC), Italy.

Purpose: Alpha particle treatments could enhance the probability of an immune response, which can lead to abscopal effects (AE). We report a case of a patient affected by multiple cutaneous squamous cell carcinoma (cSCC). After the treatment with diffusing alpha emitters radiation therapy (DaRT) of one lesion, an AE was observed on at least two distant ones.

Material And Methods: We investigated a case of a 65-year-old female patient with multiple synchronous lesions of the skin of lower limbs confirmed by a biopsy. Patient was enrolled in a clinical trial N.CTP-SCC-00 (NCT03015883), with the objective to assess effectiveness of DaRT technique. DaRT is based on the insertion of locally Ra-loaded seeds in a clinical target volume (CTV). Treatment plan with positron emission tomography/computed tomography (PET/CT) was used to entirely cover the CTV. Follow-up and biopsy evaluations were employed to outline the patient outcome.

Results: We performed seeds implantation according to the Paris system. At 28 day, an evident lesion shrinkage with a persistent minimal area of hyperkeratosis was noted. 76 days after implantation, a complete remission of the treated lesion was observed and an evident reduction of the area with two more distant lesion, which could be associated to an immune-mediated response. One year after the treatment, a complete remission of treated lesion was observed as well as spontaneous regression of untreated distant ones.

Conclusions: In this study, we reported evidences of an AE in cSCC stimulated by radiation and possibly mediated by immune system. In the next DaRT treatments, our intent is to monitor T-lymphocytes variations in peripheral blood in order to demonstrate indirect activation of the immune system mediated by radiation also in patients with solitary lesions, in which, by definition, an AE cannot be observed.
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http://dx.doi.org/10.5114/jcb.2019.88138DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6854861PMC
October 2019

Texture analysis in 177Lu SPECT phantom images: Statistical assessment of uniformity requirements using texture features.

PLoS One 2019 31;14(7):e0218814. Epub 2019 Jul 31.

Nuclear Medicine Unit, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola, Forli-Cesena, Italy.

The purpose of this study was to apply texture analysis (TA) to evaluate the uniformity of SPECT images reconstructed with the 3D Ordered Subsets Expectation Maximization (3D-OSEM) algorithm. For this purpose, a cylindrical homogeneous phantom filled with 177Lu was used and a total of 24 spherical volumes of interest (VOIs) were considered inside the phantom. The location of the VOIs was chosen in order to define two different configurations, i.e. gravity and radial configuration. The former configuration was used to investigate the uniformity of distribution of 177Lu inside the phantom, while the latter configuration was used to investigate the lack of uniformity from center towards edge of the images. For each VOI, the trend of different texture features considered as a function of 3D-OSEM updates was investigated in order to evaluate the influence of reconstruction parameters. TA was performed using CGITA software. The equality of the average texture feature trends in both spatial configurations was assumed as the null hypothesis and was tested by functional analysis of variance (fANOVA). With regard to the gravity configuration, no texture feature rejected the null hypothesis when the number of subsets increased. For the radial configuration, the statistical analysis revealed that, depending on the 3D-OSEM parameters used, a few texture features were capable of detecting the non-uniformity of 177Lu distribution inside the phantom moving from the center of the image towards its edge. Finally, cross-correlation coefficients were calculated to better identify the features that could play an important role in assessing quality assurance procedures performed on SPECT systems.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0218814PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6668785PMC
February 2020

Influence of gray level discretization on radiomic feature stability for different CT scanners, tube currents and slice thicknesses: a comprehensive phantom study.

Acta Oncol 2017 Nov 8;56(11):1544-1553. Epub 2017 Sep 8.

a Department of Radiation Oncology (MAASTRO, the D-Lab), GROW-School for Oncology and Developmental Biology , Maastricht University Medical Centre , Maastricht , The Netherlands.

Background: Radiomic analyses of CT images provide prognostic information that can potentially be used for personalized treatment. However, heterogeneity of acquisition- and reconstruction protocols influences robustness of radiomic analyses. The aim of this study was to investigate the influence of different CT-scanners, slice thicknesses, exposures and gray-level discretization on radiomic feature values and their stability.

Material And Methods: A texture phantom with ten different inserts was scanned on nine different CT-scanners with varying tube currents. Scans were reconstructed with 1.5 mm or 3 mm slice thickness. Image pre-processing comprised gray-level discretization in ten different bin widths ranging from 5 to 50 HU and different resampling methods (i.e., linear, cubic and nearest neighbor interpolation to 1 × 1 × 3 mm voxels) were investigated. Subsequently, 114 textural radiomic features were extracted from a 2.1 cm sphere in the center of each insert. The influence of slice thickness, exposure and bin width on feature values was investigated. Feature stability was assessed by calculating the concordance correlation coefficient (CCC) in a test-retest setting and for different combinations of scanners, tube currents and slice thicknesses.

Results: Bin width influenced feature values, but this only had a marginal effect on the total number of stable features (CCC > 0.85) when comparing different scanners, slice thicknesses or exposures. Most radiomic features were affected by slice thickness, but this effect could be reduced by resampling the CT-images before feature extraction. Statistics feature 'energy' was the most dependent on slice thickness. No clear correlation between feature values and exposures was observed.

Conclusions: CT-scanner, slice thickness and bin width affected radiomic feature values, whereas no effect of exposure was observed. Optimization of gray-level discretization to potentially improve prognostic value can be performed without compromising feature stability. Resampling images prior to feature extraction decreases the variability of radiomic features.
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http://dx.doi.org/10.1080/0284186X.2017.1351624DOI Listing
November 2017

Cold pressor test using strain-gauge plethysmography.

Adv Physiol Educ 2016 Sep;40(3):410-7

Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy; and.

This laboratory activity is designed to teach students how to measure forearm muscle blood flow (FBF) to describe the mechanisms of peripheral blood flow thermal regulation in healthy subjects. The cold pressor test (CPT) is the clinical procedure used in the experiment to induce arterial vasoconstriction. Strain-gauge plethysmography is applied on the patient's forearm to noninvasive monitor vasoconstriction effects on local blood perfusion and physiological parameters such as blood pressure (BP) and heart rate (HR). Patients with an altered peripheral vascular resistance (e.g., in hypertension) have different responses to the CPT from healthy subjects. To date, experimental evidence remains unexplained, as we do not know if the BP and HR increase is caused by a decrease in flow rate or an increase in peripheral vascular resistance during the test. To clarify this situation, we have to quantify the parameter we assume is being conditioned by the regulatory physiological intervention, i.e., peripheral vascular resistance. Peripheral vascular resistance quantification can be calculated as the ratio between muscle flow and mean arterial pressure. Students will learn how to apply the instrumental procedure to collect and analyze data before, during, and after the CPT and to describe the physiological responses of the peripheral vascular system to external stressors. They will also learn how to distinguish healthy from pathological responses on the basis of how sympathetic nervous system reactions influence the biomechanics of peripheral vessels.
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http://dx.doi.org/10.1152/advan.00096.2015DOI Listing
September 2016

Multiscale 3-D + T intracranial aneurysmal flow vortex detection.

IEEE Trans Biomed Eng 2015 May 6;62(5):1355-62. Epub 2015 Jan 6.

Objective: Characteristics of vortices within intracranial aneurysmal flow patterns have been associated with increased risk of rupture. The classifications of these vortex characteristics are commonly based upon qualitative scores, and are, therefore, subjective to user interpretation. We present a quantitative method for automatic time-resolved characterization of 3-D flow patterns and vortex detection within aneurysms.

Methods: Our approach is based upon the combination of kernel deconvolution and Jacobian analysis of the velocity field. The deconvolution approach is accurate in detecting vortex centers but cannot discriminate between vortices and high-shear regions. Therefore, this approach is combined with analysis of the Jacobian of the velocity field. Scale-space theory is used to evaluate aneurysmal flow velocity fields at various scales.

Results: The proposed algorithm is applied to computational fluid dynamics and time-resolved 3-D phase-contrast magnetic resonance imaging of aneurysmal flow.

Conclusion: Results show that the proposed algorithm efficiently detects, visualizes, and quantifies vortices in intracranial aneurysmal velocity patterns at multiple scales and follows the temporal evolution of these patterns.

Significance: Quantitative analysis performed with this method has the potential to reduce interobserver variability in aneurysm classification.
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http://dx.doi.org/10.1109/TBME.2014.2387874DOI Listing
May 2015

Mechanical aspects of CO₂ angiography.

Phys Med 2013 Jan 3;29(1):33-8. Epub 2011 Dec 3.

Cardiovascular Dept., University of Bologna, Via Massarenti 9, 40138 Bologna, Italy.

The aim of this paper is to clarify some physical-mechanical aspects involved in the carbon dioxide angiography procedure (CO₂ angiography), with a particular attention to a possible damage of the vascular wall. CO₂ angiography is widely used on patients with iodine intolerance. The injection of a gaseous element, in most cases manually performed, requires a long training period. Automatic systems allow better control of the injection and the study of the mechanical behaviour of the gas. CO₂ injections have been studied by using manual and automatic systems. Pressures, flows and jet shapes have been monitored by using a cardiovascular mock. Photographic images of liquid and gaseous jet have been recorded in different conditions, and the vascular pressure rises during injection have been monitored. The shape of the liquid jet during the catheter washing phase is straight in the catheter direction and there is no jet during gas injection. Gas bubbles are suddenly formed at the catheter's hole and move upwards: buoyancy is the only governing phenomenon and no bubbles fragmentation is detected. The pressure rise in the vessel depends on the injection pressure and volume and in some cases of manual injection it may double the basal vascular pressure values. CO₂ angiography is a powerful and safe procedure which diffusion will certainly increase, although some aspects related to gas injection and chamber filling are not jet well known. The use of an automatic system permits better results, shorter training period and limitation of vascular wall damage risk.
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http://dx.doi.org/10.1016/j.ejmp.2011.11.003DOI Listing
January 2013
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