10 research outputs found
Range margin reduction in carbon ion therapy: potential benefits of using radioactive ion beams
Radiotherapy with heavy ions, in particular, 12C beams, is one of the most
advanced forms of cancer treatment. Sharp dose gradients and high biological
effectiveness in the target region make them an ideal tool to treat deep-seated
and radioresistant tumors, however, at the same time, sensitive to small errors
in the range prediction. Safety margins are added to the tumor volume to
mitigate these uncertainties and ensure its uniform coverage, but during the
irradiation they lead to unavoidable damage to the surrounding healthy tissue.
To fully exploit the benefits of a sharp Bragg peak, a large effort is put into
establishing precise range verification methods for the so-called image-guided
radiotherapy. Despite positron emission tomography being widely in use for this
purpose in 12C ion therapy, the low count rates, biological washout, and broad
shape of the activity distribution still limit its precision to a few
millimeters. Instead, radioactive beams used directly for treatment would yield
an improved signal and a closer match with the dose fall-off, potentially
enabling precise in vivo beam range monitoring. We have performed a treatment
planning study to estimate the possible impact of the reduced range
uncertainties, enabled by radioactive 11C beams treatments, on sparing critical
organs in the tumor proximity. We demonstrate that (i) annihilation maps for
11C ions can in principle reflect even millimeter shifts in dose distributions
in the patient, (ii) outcomes of treatment planning with 11C beams are
significantly improved in terms of meeting the constraints for the organs at
risk compared to 12C plans, and (iii) less severe toxicities for serial and
parallel critical organs can be expected following 11C treatment with reduced
range uncertainties, compared to 12C treatments
HCV-genotype 3h, a difficult-to-diagnose sub-genotype in the DAA era
No data are available on the clinical presentation and virological pattern in the case of failure to IFN-free regimens in patients with genotype 3h. In this paper authors identified the virological and clinical characteristics of patients with genotype 3h treated with suboptimal or not indicated Interferon (IFN)-free regimens for the misclassification of HCV genotype METHODS: 87 consecutive patients with failure to an IFN-free regimen were re-tested for HCV genotype by HCV NS5B sequencing; the 26 patients identified as harboring HCV-3 were enrolled
Stereotactic Radiation Therapy for Brain Metastases: Factors Affecting Outcomes and Radiation Necrosis
Stereotactic radiation therapy (SRT) is a proven effective treatment for brain metastases (BM); however, symptomatic radiation necrosis (RN) is a late effect that may impact on patient’s quality of life. The aim of our study was to retrospectively evaluate survival outcomes and characterize the occurrence of RN in a cohort of BM patients treated with ablative SRT at Federico II University Hospital. Clinical and dosimetric factors of 87 patients bearing a total of 220 BMs treated with SRT from 2016 to 2022 were analyzed. Among them, 46 patients with 127 BMs having clinical and MRI follow-up (FUP) ≥ 6 months were selected for RN evaluation. Dosimetric parameters of the uninvolved brain (brain without GTV) were extracted. The crude local control was 91% with neither clinical factors nor prescription dose correlating with local failure (LF). At a median FUP of 9 (1–68) months, the estimated median overall survival (OS), progression-free survival (PFS), and brain progression-free survival (bPFS) were 16, 6, and 9 months, respectively. The estimated OS rates at 1 and 3 years were 59.8% and 18.3%, respectively; bPFS at 1 and 3 years was 29.9% and 13.5%, respectively; PFS at 1 and 3 years was 15.7% and 0%, respectively; and local failure-free survival (LFFS) at 1 and 3 years was 87.2% and 83.8%, respectively. Extracranial disease status was an independent factor related to OS. Fourteen (30%) patients manifested RN. At multivariate analysis, adenocarcinoma histology, left location, and absence of chemotherapy were confirmed as independent risk factors for any-grade RN. Nine (20%) patients developed symptomatic (G2) RN, which improved or stabilized after 1–16 months of steroid therapy. With prompt recognition and, when necessary, medical therapy, RN radiological and clinical amelioration can be obtained
Potential benefits of using radioactive ion beams for range margin reduction in carbon ion therapy
Abstract Sharp dose gradients and high biological effectiveness make ions such as 12C an ideal tool to treat deep-seated tumors, however, at the same time, sensitive to errors in the range prediction. Tumor safety margins mitigate these uncertainties, but during the irradiation they lead to unavoidable damage to the surrounding healthy tissue. To fully exploit the Bragg peak benefits, a large effort is put into establishing precise range verification methods. Despite positron emission tomography being widely in use for this purpose in 12C therapy, the low count rates, biological washout, and broad activity distribution still limit its precision. Instead, radioactive beams used directly for treatment would yield an improved signal and a closer match with the dose fall-off, potentially enabling precise in vivo beam range monitoring. We have performed a treatment planning study to estimate the possible impact of the reduced range uncertainties, enabled by radioactive 11C ions treatments, on sparing critical organs in tumor proximity. Compared to 12C treatments, (i) annihilation maps for 11C ions can reflect sub- millimeter shifts in dose distributions in the patient, (ii) outcomes of treatment planning with 11C significantly improve and (iii) less severe toxicities for serial and parallel critical organs can be expected
Low prevalence of HTLV1/2 infection in a population of immigrants living in southern Italy.
To assess the prevalence of HTLV-1 and HTLV-2 infections in a cohort of immigrants living in southern Italy.We screened for antibody to HTLV-1/2 infection 1,498 consecutive immigrants born in endemic areas (sub-Saharan Africa or southern-Asia) by a commercial chemiluminescent microparticle immunoassay. If confirmed in a Western blot assay, which differentiates anti-HTLV-1 from anti-HTLV-2, the positive sera were tested for specific HTLV RNA by a home-made PCR. The immigrants investigated were more frequently males (89.05%), young (median age 26 years), with a low level of education (median schooling 6 years), born in sub-Saharan Africa (79.70%). They had been living in Italy for a median period of 5 months. Only one (0.07%) subject was anti-HTLV-1 -positive/HTLV-1 RNA-negative; he was an asymptomatic 27-year-old male from Nigeria with 6 years' schooling who stated unsafe sexual habits and unsafe injection therapy.The data suggest screening for HTLV1 and HTLV-2 infections all blood donors to Italy from endemic countries at least on their first donation; however, a cost-effectiveness study is needed to clarify this topic
Demographic, virological and clinical characteristics of all patients.
<p>Demographic, virological and clinical characteristics of all patients.</p
Region of origin of 1,498 immigrants enrolled.
<p>Region of origin of 1,498 immigrants enrolled.</p
VIROLOGICAL PATTERNS OF HCV PATIENTS WITH FAILURE TO INTERFERON-FREE REGIMENS
The study characterized the virological patterns and the resistance-associated substitutions (RASs) in patients with failure to IFN-free regimens enrolled in the real-life setting