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• Ion recombination, polarity and charge multiplication effect. • Carbon ions radiotherapy. • High dose per fraction proton eye treatments. • Dosimetry with small-gap plane-parallel ionization chamber. The aim of this work was the investigation of the ion recombination and polarity factors (k sat ad k pol) for a PTW Advanced Markus ionization chamber exposed to proton and carbon ion beams at the Centro Nazionale di Adroterapia Oncologica. Measurements with protons were specifically dedicated for ocular treatments, in the low energy range and for small, collimated scanning fields. For both protons and carbon ions, several measurements were performed by delivering a 2D single energy layer of 3x3 cm2 and homogeneous, biologically-optimized SOBPs. Data were collected at different depths in water, by varying the voltage values of the ionization chamber and for two different dose rates (the nominal one and one reduced to 20% of it). The k sat -values were determined from extrapolation of the saturation curves. Furthermore k pol -values were calculated using the recommendations from the International Atomic Energy Agency (IAEA) Technical Report Series (TRS)-398 Code of Practice. Results showed that the Advanced Markus performs optimally in this clinical scenario characterized by small treatment volumes and high dose gradients although for both particle types, but particularly for carbon ions, a charge multiplication effect up to 1.7% occurs at voltage higher than 150 V. For protons, both the ion recombination and polarity corrections were always smaller than 0.3%, for all the analysed cases and adopted dose rates, so not affecting the dosimetric measurements for clinical routine. For carbon ions the polarity effect can be neglected while ion recombination has to be carefully calculated and cannot be neglected since corrections even higher than 1% can be found, especially at high LET measuring points. [ABSTRACT FROM AUTHOR]

Purpose The aim of this study was to evaluate the dosimetric impact caused by recently introduced carbon fiber reinforced polyetheretherketone (CF/PEEK) stabilization devices, in comparison with conventional titanium (Ti) implants, for post-operative particle therapy (PT). Methods As a first step, protons and carbon ions Spread-Out Bragg Peaks (SOBPs) were delivered to CF/PEEK and Ti screws. Transversal dose profiles were acquired with EBT3 films to evaluate beam perturbation. Effects on image quality and reconstruction artifacts were then investigated. CT scans of CF/PEEK and Ti implants were acquired according to our clinical protocol and Hounsfield Unit (HU) mean values were evaluated in three regions of interest. Implants and artifacts were then contoured in the sample CT scans, together with a target volume to simulate a spine tumor. Dose calculation accuracy was assessed by comparing optimized dose distributions with Monte Carlo simulations. In the end, the treatment plans of nine real patients (seven with CF/PEEK and two with Ti stabilization devices) were retrospectively analyzed to evaluate the dosimetric impact potentially occurring if improper management of the spine implant was carried out. Results As expected, CF/PEEK screw caused a very slight beam perturbation in comparison with Ti ones, leading to a lower degree of dose degradation in case of contouring and/or set-up uncertainties. Furthermore, CF/PEEK devices did not determine appreciable HU artifacts on CT images thus improving image quality and, as a final result, dose calculation accuracy. Conclusions CF/PEEK spinal fixation devices resulted dosimetrically more suitable than commonly-used Ti implants for post-operative PT. [ABSTRACT FROM AUTHOR]

Introduction Pencil beam scanning technique used at CNAO requires beam characteristics to be carefully assessed and periodically checked to guarantee patient safety. This study aimed at characterizing the Lynx® detector (IBA Dosimetry) for commissioning and periodic quality assurance (QA) for proton and carbon ion beams, as compared to EBT3 films, currently used for QA checks. Methods and materials The Lynx® is a 2-D high-resolution dosimetry system consisting of a scintillating screen coupled with a CCD camera, in a compact light-tight box. The scintillator was preliminarily characterized in terms of short-term stability, linearity with number of particles, image quality and response dependence on iris setting and beam current; Lynx® was then systematically tested against EBT3 films. The detector response dependence on radiation LET was also assessed. Results Preliminary results have shown that Lynx is suitable to be used for commissioning and QA checks for proton and carbon ion scanning beams; the cross-check with EBT3 films showed a good agreement between the two detectors, for both single spot and scanned field measurements. The strong LET dependence of the scintillator due to quenching effect makes Lynx® suitable only for relative 2-D dosimetry measurements. Conclusion Lynx® appears as a promising tool for commissioning and periodic QA checks for both protons and carbon ion beams. This detector can be used as an alternative of EBT3 films, allowing real-time measurements and analysis, with a significant time sparing. [ABSTRACT FROM AUTHOR]

Highlights • The patient complained of dysphagia and respiratory difficulty. • He had not shown any signs of systemic amyloidosis. • The patient underwent total thyroidectomy. • Based on morphological and histochemical features, the diagnosis of "amyloid goiter" was rendered. Abstract Introduction Amyloid goiter is due to the deposition of amyloid in the thyroid, resulting with enlargement of the gland and compressive symptoms. Case We herein present a case of a 45-year-old male patient who complained of a big swelling in the neck. Ultrasound showed an enlarged thyroid gland with mediastinal involvement. The multinodular appearance was consistent with the diagnosis of multinodular goiter. He had a history of multiple myeloma but no sign of systemic amyloidosis. Discussion Thyroid gland was removed and the histopathological examination revealed a diffuse deposition of amyloid associated with metaplastic lipomatosis of the stroma. Conclusions The treatment of choice in patients with amyloid goiter is total thyroidectomy to solve compression symptoms. [ABSTRACT FROM AUTHOR]

Improved conformity in carbon-ion radiation therapy (CIRT) with respect to photon RT comes at the cost of a potential reduced delivery robustness due to patient setup uncertainties, approximations in dose calculations and carbon-ion range uncertainties. This work presents preliminary results of a study aiming to address these challenges using 3D polymer gel dosimetry in anthropomorphic and inhomogeneous geometry. All irradiations were performed at a synchrotron facility, in one of the treatment rooms equipped with a horizontal fixed beam line and pencil beam scanning (PBS) modality. For basic dosimetric characterization, carbon pristine Bragg peaks (BP) (ranges 30, 70, 90 mm in water) and a spread-out BP (SOBP) (range 115 mm and modulation 40 mm) were delivered on a cylindrical PMMA container filled with VIPAR polymer gel. An anthropomorphic phantom equipped with a cylindrical polymer gel insert was used for the irradiation of a pseudo-clinical CIRT plan, following all the steps of the standard clinical workflow, from simulation CT to irradiation. Two contralateral beams were optimized with a TPS (v.8b) to deliver 15 Gy (RBE) on a target located approximately at the center of the brain, in proximity of critical OARs such as brainstem and optical pathways. The phantom was then MRI scanned post-irradiation to retrieve the irradiated brain volume in 3D. The measured irradiated volume was compared against corresponding TPS derived data. Carbon-ion range was spatially verified with an accuracy of < 1 mm. For both the pristine BP and the SOBP irradiations. A significant deviation of the polymer gels' response on high-LET has been observed, as expected from previous studies with proton irradiations. For the pseudo-clinical treatment plan, a qualitative comparison between doses measured in polymer gels, against the corresponding TPS calculations, revealed a satisfying geometric accuracy of dose delivery in 3D, thus showing a high 3D geometrical accuracy of dose delivery in a typical standard clinical workflow. In this work, we showed that patient-specific 3D polymer gel dosimetry is applicable to CIRT, as a valid tool to evaluate dosimetric and spatial plan accuracy in the clinical environment. As expected, the LET dependence of polymer gel's response, especially in the high-LET region, poses severe limitations for accurate dose measurements. Nevertheless, the proposed methodology is a promising efficient and safe clinical way for verifying such a complex RT technique. [ABSTRACT FROM AUTHOR]

Purpose Around 10 centers worldwide treat ocular tumors with proton therapy, all with dedicated eyelines. Our synchrotron-based facility is equipped with general-purpose fixed beamlines; proton and carbon ion treatments are delivered with pencil beam scanning modality (range in water 3 ÷ 32 cm). Recently, our proton beamline was adapted to treat also ocular diseases. The main dosimetric properties of this new eyeline are described in this work. Methods A 3 cm water-equivalent range shifter (RS) was placed along the beamline to reach shallower penetration depths. In order to achieve steep lateral dose gradients, the position of the RS and patient-specific collimator were simulated using MonteCarlo (MC) FLUKA code. Lateral dose profiles were measured with gafchromic EBT3 films to evaluate lateral penumbra width and dose homogeneity. Several beam scanning patterns were tested. Depth-dose distributions (DDDs) were measured with the Peakfinder system. To obtain uniform dose distributions (Spread-Out Bragg Peaks, SOBPs), the weights of each DDD were optimized simulating different targets. Absorbed doses were then measured in water with an advanced Markus chamber. Neutron dose at the contralateral eye was also evaluated with passive bubble dosimeters. Results MC simulations and experimental results showed that maximizing the distance between RS and collimator reduces the lateral dose penumbra of the collimated beam and increases field transversal dose homogeneity. Therefore, RS and patient-specific collimator were placed at about 98 cm (behind beam monitors) and 6 cm from the isocenter, respectively. The lateral penumbra (distal fall-off) ranged between 1.0 and 1.8 mm (1.0 and 1.6 mm). The measured SOBP doses were in very good agreement with MC simulations, as shown in Fig. 1. The mean neutron dose at the contralateral eye was 68.8 ± 10.2 μSv/Gy. Conclusions Our eyeline satisfied the requirements to treat ocular tumors. The first ocular patient was treated in August 2016. Around 60 patients have been treated so far. [ABSTRACT FROM AUTHOR]

Pencil beam scanning technique used at CNAO requires beam characteristics to be carefully and periodically checked to guarantee patient safety. Radiochromic films are used within daily QA checks. This study aimed at characterizing the Lynx PT system (IBA Dosimetry) and assessing its suitability for QA tests, for proton and carbon ion beams. The Lynx PT is a 2D high-resolution dosimetry system consisting of a scintillating screen coupled with a CCD camera, in a compact light-tight box. A dedicated software is used for image acquisition, raw data correction and fast data analysis. Lynx was characterized in terms of short-term stability, image geometrical distortion, uniformity, signal proportionality, response dependence on IRIS and on particle intensity, particle energy and type. Irradiations were performed at the Centro Nazionale di Adroterapia Oncologica (CNAO) for both protons and carbon ions. Measurements with Lynx were compared to those made with EBT3 reference films. The detector response dependence on radiation LET was also investigated. Lynx basic characterization results have shown a proportional behavior with delivered number of particles. Strong dependence of the acquired signal on beam energy and particle type was found. No significant differences in the investigated beam parameters measured with Lynx and EBT3 film were observed. The detector also showed good performances in term of image uniformity and geometrical distortion. The Lynx PT system appears as a promising tool for measurements for both single pencil beam and scanned beam, enabling fast QA and beam optics optimization checks. [ABSTRACT FROM AUTHOR]

Abstract: Isolated chloromas (granulocytic sarcomas) are rare tumours. Chloromas are masses composed of immature granulocytic cells. Granulocytic sarcoma occurs primarily in patients with acute myelogenous leukaemia, but can also arise in patients with other myeloproliferative disorders. We present an adult case of chloroma in HIV patient, which occurred as sudden death. Skin examination of right thigh showed dyschromia. Longitudinal incision of muscle revealed a “dark green” infiltration. Pathology showed in muscle fragments a infiltrate of granulocytes. The histologic sections of the excised tumour confirmed the cytologic diagnosis of chloroma. [Copyright &y& Elsevier]

Abstract: Splenectomized patients are likely to suffer from severe infections, such as sepsis and meningitis. This syndrome is called overwhelming postsplenectomy infection (OPSI) in Europe and America. We present an adult case of OPSI syndrome, which occurred as respiratory insufficiency, and thrombocytopenia. The course is rapid, the clinical symptoms are serious, and the prognosis is very poor. Clinical examination showed cyanosis, mandibular hypertonia, psychomotor anxiety and purpura. Laboratory findings were thrombocytopenia, leukocytosis, hypoglycemia and altered coagulation parameters. A chest X-ray showed right pulmonary aspecific thickening. The autopsy findings occurred as Waterhouse–Friderichsen syndrome. [Copyright &y& Elsevier]

Twenty-nine strains of mastitis pathogens were used to study the antibacterial activity of the cell-free supernatants (CFS) of 25 strains of Lactococcus lactis ssp. lactis. Out of the tested strains, only the CFS of L. lactis LL11 and SL153 were active, inhibiting and killing most of the pathogens. By means of ultraperformance liquid chromatography/high resolution mass spectrometry, they were shown to produce nisin A, a class I bacteriocin. A variable sensitivity to nisin A-containing CFS was observed among Streptococcus uberis and Enterococcus faecalis strains. Nonetheless, Streptococcus agalactiae, Strep. uberis, and E. faecalis displayed high minimum inhibitory concentration values, reaching 384 arbitrary units/mL. Interestingly, the minimum inhibitory values and the bactericidal concentrations were almost identical among them for each of the 2 stains, LL11 and SL153. Staphylococci were, on average, less sensitive than streptococci, but the 2 CFS inhibited and killed, at different dilutions, strains of methicillin-resistant Staphylococcus aureus. The immune response to nisin A-containing CFS was tested using the bovine mammary epithelial cell line BME-UV1. Application of CFS did not damage epithelial integrity, as demonstrated by the higher activity of N-acetyl-β-d-glucosaminidase (NAGase) and lysozyme inside the cells, in both treated and control samples. On the other hand, the increase of released NAGase after 15 to 24 h of treatment with LL11 or SL153 live cultures demonstrated an inflammatory response of epithelial cells. Similarly, a significantly higher lysozyme activity was detected in the cells treated with LL11 live culture confirming the stimulation of lysosomal activity. The treatment of epithelial cells with SL153 live culture induced a significant tumor necrosis factor-α downregulation in the cells, but did not influence IL-8 expression. The control of tumor necrosis factor-α release could be an interesting approach to reduce the symptoms linked to clinical intramammary infections. Due to their antibacterial activity and to the stimulation of lysosomal activity of mammary epithelial cells, the L. lactis strains SL153 and LL11 could be of interest for the development of alternative intramammary treatments to control cow mastitis. [ABSTRACT FROM AUTHOR]