116 research outputs found
Radiotherapy of large target volumes in Hodgkin's lymphoma: normal tissue sparing capability of forward IMRT versus conventional techniques
<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
The effect of FK506 on transforming growth factor beta signaling and apoptosis in chronic lymphocytic leukemia B cells.
Background Loss of response to transforming growth factor-beta (TGF-beta) is thought to contribute to the progression of chronic lymphocytic leukemia. Recent findings of over-activation of the TGF-beta signal in FKBP12-knockout mouse prompted us to investigate whether FK506, the canonical ligand of FKBP, can activate the TGF-beta signal in chronic lymphocytic leukemia. Design and Methods We studied 62 chronic lymphocytic leukemia samples from patients with Rai/Binet stage 0 to 4 disease. The TGF-beta signal was investigated by western blotting and flow cytometry. The levels of Bcl2-family members and death-associated-protein kinase were also investigated by western blotting, whereas apoptosis was studied in flow cytometry. Down-modulation of FKBP12 was obtained by gene silencing with short interfering RNA. Results Twenty-two out of 62 chronic lymphocytic leukemia samples were sensitive to TGF-beta-induced apoptosis. All but two of the responsive samples underwent apoptosis also when cultured with FK506, but not with cyclosporine. Thirteen samples that were not sensitive to TGF-beta were sensitive to FK506. Overall, response to FK506 occurred in 33 samples. FK506 induced Smad2 phosphorylation and nuclear translocation. Accordingly, death-associated-protein kinase, a transcriptional target of Smad, was induced. At the same time, Bcl-2 and Bcl-xL levels decreased whereas the levels of Bim and Bmf increased. A loss of mitochondrial membrane potential preceded caspase activation and cell death. FK506 removed FKBP12 from its binding to the TGF-beta-receptor. FKBP12 release activated the receptor-kinase activity as suggested by the enhanced levels of phospho-Smad found in cells depleted of FKBP12. Conclusions Our study shows that most chronic lymphocytic leukemia cells escape the homeostatic control of TGF-beta and that FK506 restores the TGF-beta signal in a proportion of non-responsive samples. We demonstrated that FK506 activates TGF-beta receptor I kinase activity in chronic lymphocytic leukemia, which transduces apoptosis by a mitochondrial-dependent pathway
Radiation therapy in primary orbital lymphoma: a single institution retrospective analysis
<p>Abstract</p> <p>Background</p> <p>Primary orbital lymphoma is a rare disease that accounts for 10% of all orbital tumors. Radiotherapy on the orbital cavity is the treatment of choice for this unusual presentation of localized non-Hodgkin's lymphoma (NHL). The aim of this study is to retrospectively evaluate the effectiveness and the toxicity of radiation treatment in patients with primary orbital lymphoma.</p> <p>Methods</p> <p>Forty-seven consecutive patients having primary orbital lymphoma treated in our department between May 1983 and September 2006 were investigated in a retrospective study. Either <sup>60</sup>Co Îł rays or 6 MV X rays were used to deliver daily fractions of 1.8 or 2.0 Gy, 5 times/week, with total doses ranging from 34.2 to 50 Gy. Forty-three patients had stage IE, three had stage II and one stage IV disease. Thirty-eight patients had marginal zone B-cell lymphoma, 5 diffuse large B cell lymphoma, 3 mantle cell lymphoma and 1 Burkitt lymphoma. Local control (LC), disease free survival (DFS), overall survival (OS) and late side effects were evaluated in all patients.</p> <p>Results</p> <p>With a median follow up of 45 months, LC was obtained in 100% of patients. The estimated 5- and 7-year DFS rates were 75.8% and 55.3%, and the 5- and 7-year OS rates were 88.7% and 79.9% respectively. Acute toxicity was minimal. Late toxicity such as cataract, keratitis, retinopathy and xerophthalmia occurred respectively in 12 (25.5%), 5 (10.6%), 1 (2.1%), and 9 (19.1%) patients.</p> <p>Conclusion</p> <p>Radiotherapy is an effective and at the same time well tolerated treatment for primary orbital lymphoma.</p
Chronic cerebrospinal venous insufficiency in multiple sclerosis: a highly prevalent age-dependent phenomenon
BACKGROUND: This study aimed to investigate the prevalence and clinical relevance of chronic cerebrospinal venous insufficiency (CCSVI) in multiple sclerosis (MS) patients and healthy controls using extra- and intracranial colour Doppler sonography. METHODS: We examined 146 MS patients, presenting with a clinically isolated syndrome, relapsing-remitting, secondary progressive, or primary progressive MS, and 38 healthy controls. Sonographic examination was performed according to Zamboni’s protocol and was performed by three independent sonographers. The results of sonographic examination were compared with clinical and demographic characteristics of the patients. RESULTS: CCSVI, defined as the presence of at least two positive Zamboni’s criteria, was found in 76% of MS patients and 16% of control subjects. B-mode anomalies of internal jugular veins, such as stenosis, malformed valves, annuli, and septa were the most common lesions detected in MS patients (80.8%) and controls (47.4%). We observed a positive correlation between sonographic diagnosis of CCSVI and the patients’ age (p = 0.003). However, such a correlation was not found in controls (p = 0.635). Notably, no significant correlations were found between sonographic signs of CCSVI and clinical characteristics of MS, except for absent flow in the jugular veins, which was found more often in primary (p<0.005) and secondary (p<0.05) progressive patients compared with non-progressive patients. Absent flow in jugular veins was significantly correlated with patients’ age (p < 0.0001). CONCLUSIONS: Sonographically defined CCSVI is common in MS patients. However, CCSVI appears to be primarily associated with the patient’s age, and poorly correlated with the clinical course of the disease
Development of multivariate NTCP models for radiation-induced hypothyroidism: a comparative analysis
Reproducibility of Shear Wave Elastography.xlsx
Dataset of subjects in which were performed a hepatic shear wave elastography and a measure of fibrosis. The fibrosis stage was classified with Metavir score
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