128 research outputs found

    Radiotherapy of large target volumes in Hodgkin's lymphoma: normal tissue sparing capability of forward IMRT versus conventional techniques

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    <p>Abstract</p> <p>Background</p> <p>This paper analyses normal tissue sparing capability of radiation treatment techniques in Hodgkin's lymphoma with large treatment volume.</p> <p>Methods</p> <p>10 patients with supradiaphragmatic Hodgkin's lymphoma and planning target volume (PTV) larger than 900 cm<sup>3 </sup>were evaluated. Two plans were simulated for each patient using 6 MV X-rays: a conventional multi-leaf (MLC) parallel-opposed (AP-PA) plan, and the same plan with additional MLC shaped segments (forward planned intensity modulated radiation therapy, FPIMRT). In order to compare plans, dose-volume histograms (DVHs) of PTV, lungs, heart, spinal cord, breast, and thyroid were analyzed. The Inhomogeneity Coefficient (IC), the PTV receiving 95% of the prescription dose (V95), the normal tissue complication probability (NTCP) and dose-volume parameters for the OARs were determined.</p> <p>Results</p> <p>the PTV coverage was improved (mean V95<sub>AP-PA </sub>= 95.9 and IC<sub>AP-PA </sub>= 0.4 vs. V95<sub>FPIMRT </sub>= 96.8 and IC<sub>FPIMRT </sub>= 0.31, <it>p </it>≤ 0.05) by the FPIMRT technique compared to the conventional one. At the same time, NTCPs of lung, spinal cord and thyroid, and the volume of lung and thyroid receiving ≥ 30 Gy resulted significantly reduced when using the FPIMRT technique.</p> <p>Conclusions</p> <p>The FPIMRT technique can represent a very useful and, at the same time, simple method for improving PTV conformity while saving critical organs when large fields are needed as in Hodgkin's lymphoma.</p

    Correlative imaging of cystic lymphangiomas: ultrasound, CT and MRI comparison

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    Cystic lymphangioma is a rare benign lesion derived from the detachment of the lymph sacs from venous drainage systems; the treatment of choice is a surgical excision and the final diagnosis is of histological type

    R0 surgical resection of giant dedifferentiated retroperitoneal liposarcomas in the COVID era with and without nephrectomy: A case report

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    : Retroperitoneal sarcomas (RPSs) are rare findings that can grow into large masses without eliciting severe symptoms. At present, surgical resection is the only radical therapy, whenever it can be performed with the aim to achieve a complete removal of the tumor. The present report describes two consecutive cases of RPSs that resulted in dedifferentiated liposarcomas (DDLPSs) and these patients underwent R0 surgical resection with and without a nephron-sparing procedure. The diagnostic workup, the surgical approach, the impact of late surgical management due to the COVID pandemic and the latest literature on the topic are discussed and analyzed. The patients, who refused to undergo any medical examination during the prior 2 years due to the COVID pandemic, were admitted to Federico II University Hospital (Naples, Italy) complaining about weight loss and general abdominal discomfort. In the first case, a primitive giant abdominal right neoplasm of retroperitoneal origin enveloping and medializing the right kidney was observed. The second patient had a similar primitive retroperitoneal giant left neoplasm, which did not affect the kidney. Given the characteristics of the masses and the absence of distant metastases, after a multidisciplinary discussion, radical surgical removal was carried out for both patients. The lesions appeared well-defined from the surrounding tissues, and markedly compressed all the adjacent organs, without signs of infiltration. In the first patient, the right kidney was surrounded and undetachable from the tumor and it was removed en bloc with the mass. The second patient benefited from a nephron-sparing resection, due to the existence of a clear cleavage plane. The postoperative courses were uneventful. Both the histological examinations were oriented towards a DDLPS and both patients benefited from adjuvant chemotherapy. In conclusion, the treatment of giant RPS is still challenging and requires multidisciplinary treatment as well as, when possible, radical surgical removal. The lack of tissue infiltration and the avoidance of excision or reconstruction of major organs (including the kidney) could lead to an easier postoperative course and an improved prognosis. When possible, surgical management of recurrences or incompletely resected masses must be pursued. Since the COVID pandemic caused limited medicalization of a number of population groups and delayed diagnosis of other oncologic diseases, an increased number of DDLPSs could be expected in the near future

    Non-invasive diagnostic imaging of colorectal liver metastases

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    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver- directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs

    Gastrinomas and non-functioning pancreatic endocrine tumors in multiple endocrine neoplasia syndrome type-1 (MEN-1)

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    Purpose: Illustrate imaging findings of gastrinomas and non-functioning pancreatic endocrine tumors (NF-PNET) in a patient with multiple endocrine neoplasia type-1 (MEN-1) syndrome with a radiologic-pathologic correlation for both along with the results of a 13 yrs observational study. Methods: A 48 yrs old male patient with MEN-1 and a Zollinger-Ellison syndrome was submitted to a duodeno-cephalopancreatectomy (DCP) extended to the pancreatic body to remove several gastrinomas shown by an endoscopic-ultrasonography as well as a large (> 2 cm) hypo-vascular pancreatic nodule shown by a contrast-enhanced multi-detector CT (CE-MDCT). Further conventional (CT/MR) and functional imaging (68Ga-PET-DOTA-TOC) studies were performed over the next 13 years. Results: Up to 14 gastrin-positive NET-G1 (pT2,N1) as well as a single PNET-G2 (pT2,N0) were found at histo-pathology which also showed a NET-G1 in the uncinate process where CE-MDCT documented a 9 mm hyper-vascular nodule. A 7 mm pancreatic nodule with identical contrast-enhancement pattern was also shown at the level of the pancreatic tail which was left to preserve endocrine function. At this level, follow-up studies documented the occurence of a small (< 1 cm) hypo-vascular nodule which was metastatic at presentation and rapidly progressed under somastatin-analogs therapy whereas the hyper-vascular nodule remained stable over 13 years. Both the pancreatic lesion as well as the hepatic metastasis showed pathologic uptake of the radiotracer with a SUVmax of 6.3 and 29.5, respectively, allowing the patient to be scheduled for a Peptide Receptor Radionuclide Therapy performed with 29.6 GBq of 177Lu-Oxotreotide. Conclusions: Contrast-enhancement patterns are correlated with both the histological grade as well as the biological behaviour of PNETS

    Bone demineralization and vertebral fractures in endogenous cortisol excess: role of disease etiology and gonadal status

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    INTRODUCTION: The effects of endogenous cortisol (F) excess on bone mass and vertebral fractures have still not been thoroughly investigated. The aim of this cross-sectional case-control study was to investigate factors influencing bone demineralization and vertebral fractures in different conditions of F excess, i.e. Cushing's disease and adrenal and ectopic Cushing's syndrome. MATERIALS AND METHODS: Eighty consecutive patients and 80 controls were prospectively enrolled: 37 patients (21 females) with pituitary ACTH-secreting adenoma, 18 (14 females) with adrenocortical adenoma, 15 (11 females) with adrenal carcinoma of mixed secretion, and 10 (three females) with ectopic ACTH secretion. The groups had similar age. At diagnosis, bone mineral density (BMD) was determined by the dual-energy x-ray absorptiometry technique at the lumbar spine (L1-L4) and femoral neck; vertebral fractures were investigated by standard spinal radiographs. RESULTS: When comparing the groups with different etiology of F excess, the patients with ectopic ACTH secretion had higher F and lower BMD values than the other subgroups. Morning F (P = 0.03) and testosterone levels (P = 0.04) correlated with lumbar BMD. Vertebral fractures were found in 61 (76%) of the patients, were multiple in 52 (85%) of the cases, and clinically evident in 32 (52%). Only multiple fractures were more frequent in patients with ectopic ACTH hypersecretion (P &lt; 0.05). Lumbar spine BMD was the best predictor of vertebral fractures (P &lt; 0.01). Surprisingly, amenorrheic and eumenorrheic women had similar BMD values and fracture prevalence. CONCLUSION: A high prevalence (76%) of vertebral fracture was revealed, regardless of the etiology of the patients' hypercortisolism. The harmful effects of F excess at the spine were partly counterbalanced by the increased androgen production but were not affected by gonadal status in women

    Inhibition of Stearoyl-CoA desaturase 1 reverts BRAF and MEK inhibition-induced selection of cancer stem cells in BRAF-mutated melanoma

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    Combination therapy with BRAF and MEK inhibitors significantly improves survival in BRAF mutated melanoma patients but is unable to prevent disease recurrence due to the emergence of drug resistance. Cancer stem cells (CSCs) have been involved in these long-term treatment failures. We previously reported in lung cancer that CSCs maintenance is due to altered lipid metabolism and dependent upon Stearoyl-CoA-desaturase (SCD1)-mediated upregulation of YAP and TAZ. On this ground, we investigated the role of SCD1 in melanoma CSCs

    Use and Prescription of Direct Oral Anticoagulants in Older and Frail Patients with Atrial Fibrillation: A Multidisciplinary Consensus Document

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    In the last twelve years the clinical management of patients with atrial fibrillation has been revolutionised by the introduction of direct oral anticoagulants. Despite the large amount of evidence produced, some populations remain relatively poorly explored regarding the effectiveness and safety of direct oral anticoagulants, such as the oldest and/or frailest individuals. Frailty is clinical syndrome characterized by a reduction of functions and physiological reserves which results in individuals having higher vulnerability. While current evidence underlines a relationship between atrial fibrillation and frailty, particularly in determining a higher risk of adverse outcomes, data regarding effectiveness and safety of direct oral anticoagulants in frailty atrial fibrillation patients are still lacking, leaving uncertainty about how to guide prescription in this specific subgroup. On these premises, this multidisciplinary consensus document explains why it would be useful to integrate the clinical evaluation performed through comprehensive geriatric assessment to gather further elements to guide prescription of direct oral anticoagulants in such a high-risk group of patients

    Euclid: Constraining ensemble photometric redshift distributions with stacked spectroscopy

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    The ESA Euclid mission will produce photometric galaxy samples over 15000 square degrees of the sky that will be rich for clustering and weak lensing statistics. The accuracy of the cosmological constraints derived from these measurements will depend on the knowledge of the underlying redshift distributions based on photometric redshift calibrations. A new approach is proposed to use the stacked spectra from Euclid slitless spectroscopy to augment broad-band photometric information to constrain the redshift distribution with spectral energy distribution fitting. The high spectral resolution available in the stacked spectra complements the photometry and helps to break the colour-redshift degeneracy and constrain the redshift distribution of galaxy samples. We modelled the stacked spectra as a linear mixture of spectral templates. The mixture may be inverted to infer the underlying redshift distribution using constrained regression algorithms. We demonstrate the method on simulated Vera C. Rubin Observatory and Euclid mock survey data sets based on the Euclid Flagship mock galaxy catalogue. We assess the accuracy of the reconstruction by considering the inference of the baryon acoustic scale from angular two-point correlation function measurements. We selected mock photometric galaxy samples at redshift z>1 using the self-organising map algorithm. Considering the idealised case without dust attenuation, we find that the redshift distributions of these samples can be recovered with 0.5% accuracy on the baryon acoustic scale. The estimates are not significantly degraded by the spectroscopic measurement noise due to the large sample size. However, the error degrades to 2% when the dust attenuation model is left free. We find that the colour degeneracies introduced by attenuation limit the accuracy considering the wavelength coverage of Euclid near-infrared spectroscopy
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