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Beam Radiation (beam + radiation)
Kinds of Beam Radiation Terms modified by Beam Radiation Selected AbstractsExternal Beam Radiation Followed by Planned Neck Dissection and Brachytherapy for Base of Tongue Squamous Cell Carcinoma,THE LARYNGOSCOPE, Issue 10 2000David M. Kaylie MD Abstract Background Surgical resection of tongue base cancer can leave the patient with significant functional deficits. Other therapies, such as external beam radiation followed by neck dissection and radiation implants, have shown equal tumor control with good functional outcome. Methods Between March 1991 and July 1999, 12 patients at Oregon Health Sciences University, the Portland Veterans Administration Medical Center and West Virginia University School of Medicine Hospital were treated with external beam radiation followed by neck dissection and Ir192 implants. Two patients had T1 disease, two had T2, five patients had T3 tumors, and three had T4 tumors. Six had N2a necks, three had N2b necks, and three had N2c. Follow-up ranged from 13 months to 8 years. Results After external beam radiation, five patients had complete response and seven had partial response in the neck without complications. One patient underwent a unilateral radical neck dissection, eight had unilateral selective neck dissections involving levels I to IV, and three had dissections involving levels I to III. One of the five patients who had a complete clinical response in the neck had pathologically positive nodes. One patient had a pulmonary embolus that was treated and had no permanent sequelae. There were three complications from brachytherapy. Two patients had soft tissue necrosis at the primary site and one patient had radionecrosis of the mandible. All healed without further therapy. One patient had persistent disease and underwent a partial glossectomy but died of local disease. Distant metastasis developed in two patients. All others show no evidence of disease and are able to eat a normal diet by mouth. Conclusion This combination of therapies should be considered when treating tongue base cancer. [source] Analysing soil variation in two dimensions with the discrete wavelet transformEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2004R. M. Lark Summary Complex spatial variation in soil can be analysed by wavelets into contributions at several scales or resolutions. The first applications were to data recorded at regular intervals in one dimension, i.e. on transects. The theory extends readily to two dimensions, but the application to small sets of gridded data such as one is likely to have from a soil survey requires special adaptation. This paper describes the extension of wavelet theory to two dimensions. The adaptation of the wavelet filters near the limits of a region that was successful in one dimension proved unsuitable in two dimensions. We therefore had to pad the data out symmetrically beyond the limits to minimize edge effects. With the above modifications and Daubechies's wavelet with two vanishing moments the analysis is applied to soil thickness, slope gradient, and direct solar beam radiation at the land surface recorded at 100-m intervals on a 60 × 101 square grid in south-west England. The analysis revealed contributions to the variance at several scales and for different directions and correlations between the variables that were not evident in maps of the original data. In particular, it showed how the thickness of the soil increasingly matches the geological structure with increasing dilation of the wavelet, this relationship being local to the strongly aligned outcrops. The analysis reveals a similar pattern in slope gradient, and a negative correlation with soil thickness, most clearly evident at the coarser scales. The solar beam radiation integrates slope gradient and azimuth, and the analysis emphasizes the relations with topography at the various spatial scales and reveals additional effects of aspect on soil thickness. [source] Nonoperative therapies for combined modality treatment of hepatocellular cancer: expert consensus statementHPB, Issue 5 2010Roderich E. Schwarz Abstract Although surgical resection and liver transplantation are the only treatment modalities that enable prolonged survival in patients with hepatocellular carcinoma (HCC), the majority of HCC patients presents with advanced disease and do not undergo resective or ablative therapy. Transarterial chemoembolization (TACE) is indicated in intermediate/advanced stage unresectable HCC even in the setting of portal vein involvement (excluding main portal vein). Sorafenib has been shown to improve survival of patients with advanced HCC in two controlled randomized trials. Yttrium 90 is a safe microembolization treatment that can be used as an alternative to TACE in patients with advanced liver only disease or in case of portal vein thrombosis. External beam radiation can be helpful to provide local control in selected unresectable HCC. These different treatment modalities may be combined in the treatment strategy of HCC and also used as a bridge to resection or liver transplantation. Patients should undergo formal multidisciplinary evaluation prior to initiating any such treatment in order to individualize the best available options. [source] Low cost autologous peripheral blood stem cell transplantation performed in a municipal hospital for a patient with plasma cell leukaemiaINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 3 2002K. Ghosh Autologous peripheral blood stem cell transplantation (PBSCT) is a costly procedure. In India, the cost varies from US$20 000 to 25 000 and most patients cannot afford it. Using several cost-cutting measures, we were able to treat a patient with plasma cell leukaemia by autologous PBSCT. A 42-year-old-male presented with plasma cell leukaemia. He was treated with VAD therapy, followed by high-dose cyclophosphamide and granulocyte colony-stimulating factor (G-CSF) for mobilization of peripheral blood stem cells. The patient was conditioned with high dose melphalan, followed by autologous PBSCT. The procedure was performed in a municipal hospital in which there was no prior experience with stem cell transplantation. Costs were reduced by: (i) using oral medication whenever possible; (ii) having a relative of the patient prepare his food under medical guidance; (iii) starting G,CSF on day 7 rather than on day 1; (iv) short-term storage of the PBSC in an ordinary refrigerator at 4 °C without cryopreservation; (v) infusing a large number of CD34+ cells, which shortened the time to engraftment; (vi) delegating many of the functions of a marrow transplant nurse to a resident physician. The cost of transplantation was thereby reduced to about US$ 6000, with successful engraftment by day +13. The patient remained in remission for 7 months, after which he relapsed and was treated with chemotherapy and electron beam radiation to the skin. [source] Management of retinoblastoma with proximal optic nerve enhancement on MRI at diagnosisPEDIATRIC BLOOD & CANCER, Issue 4 2008Saro H. Armenian DO Abstract Background In North America, retinoblastoma rarely presents with gross clinical evidence of tumor involving the optic nerve. Extent of microscopic tumor infiltration into the postlaminar optic nerve is a significant risk factor for metastasis, especially if there is tumor at the cut end. Due to poor outcomes in patients with metastatic disease, historical treatment for patients with clinical evidence of extraocular optic nerve involvement has included upfront enucleation followed by aggressive adjuvant chemotherapy. Additional orbital irradiation is advocated for individuals with optic nerve involvement at the surgical margin. Little is known about the role of neoadjuvant therapy in the setting of orbital optic nerve enhancement on magnetic resonance imaging (MRI) at diagnosis. Methods A retrospective review of consecutive retinoblastoma cases at Childrens Hospital Los Angeles over a 3-year period (2004,2006) found to have gadolinium contrast enhancement in the proximal portion of optic nerve on MRI at diagnosis. Results Nine patients fit the inclusion criteria. Two had secondary glaucoma of a sufficient degree to cause an enlarged eye (buphthalmos). Median age at presentation was 17 months (2,36 months). All patients received neoadjuvant chemotherapy prior to enucleation. Only two received external beam radiation. All are disease-free with a median follow-up of 22 months (12,41 months). Conclusions Neoadjuvant chemotherapy is well tolerated prior to enucleation of retinoblastoma-containing eyes associated with contrast enhancement of the proximal optic nerve on MRI at diagnosis. Such an approach may be used to decrease intensity or duration of chemotherapy and need for external beam radiation. Pediatr Blood Cancer 2008;51:479,484. © 2008 Wiley-Liss, Inc. [source] Benign pineal cysts in children with bilateral retinoblastoma: A new variant of trilateral retinoblastoma?PEDIATRIC BLOOD & CANCER, Issue 7 2006Maja Beck Popovic MD Abstract Purpose Patients with hereditary retinoblastoma (Rb) develop in 4%,8% a malignant midline tumor called trilateral Rb (TRb). We report in this study on benign pineal cysts observed in patients investigated for TRb. Patients and Methods Between September 1990 and December 2001, 172 patients were screened for TRb. Ninty-five had bilateral, 77 unilateral disease. The median age at diagnosis of Rb was 7 months (range 1,26). Treatment included enucleation, local treatment with cryotherapy or photocoagulation, first-line chemotherapy (CT), thermo-chemotherapy (TCT), Ruthenium plaque, and, rarely, external beam radiation (EBR). Results TRb was found in 5/95 patients (5.3%) with bilateral disease. Interestingly, five other patients (5.3%) presented a pineal cyst on magnetic resonance imaging (MRI). No cysts were recorded in the 77 patients with unilateral disease. This difference was statistically significant (P,<,0.05). The median age at diagnosis of the pineal cyst was 26 months (range 16,80), much younger than reported in literature for healthy children. Four of five patients with TRb died of the disease, while all the patients with pineal cysts remained stable and asymptomatic during a median follow-up of 41 months (range 37,54). Conclusions This report describes benign cystic lesions of the pineal gland in patients with hereditary Rb, suggesting a benign variant of TRb. Underlying possible pathogenetic mechanisms are discussed. © 2005 Wiley-Liss, Inc. [source] External Beam Radiation Followed by Planned Neck Dissection and Brachytherapy for Base of Tongue Squamous Cell Carcinoma,THE LARYNGOSCOPE, Issue 10 2000David M. Kaylie MD Abstract Background Surgical resection of tongue base cancer can leave the patient with significant functional deficits. Other therapies, such as external beam radiation followed by neck dissection and radiation implants, have shown equal tumor control with good functional outcome. Methods Between March 1991 and July 1999, 12 patients at Oregon Health Sciences University, the Portland Veterans Administration Medical Center and West Virginia University School of Medicine Hospital were treated with external beam radiation followed by neck dissection and Ir192 implants. Two patients had T1 disease, two had T2, five patients had T3 tumors, and three had T4 tumors. Six had N2a necks, three had N2b necks, and three had N2c. Follow-up ranged from 13 months to 8 years. Results After external beam radiation, five patients had complete response and seven had partial response in the neck without complications. One patient underwent a unilateral radical neck dissection, eight had unilateral selective neck dissections involving levels I to IV, and three had dissections involving levels I to III. One of the five patients who had a complete clinical response in the neck had pathologically positive nodes. One patient had a pulmonary embolus that was treated and had no permanent sequelae. There were three complications from brachytherapy. Two patients had soft tissue necrosis at the primary site and one patient had radionecrosis of the mandible. All healed without further therapy. One patient had persistent disease and underwent a partial glossectomy but died of local disease. Distant metastasis developed in two patients. All others show no evidence of disease and are able to eat a normal diet by mouth. Conclusion This combination of therapies should be considered when treating tongue base cancer. [source] Evaluation of [11C]-choline positron-emission/computed tomography in patients with increasing prostate-specific antigen levels after primary treatment for prostate cancerBJU INTERNATIONAL, Issue 4 2007Ludwig Rinnab OBJECTIVE To evaluate [11C]-choline positron-emission tomography (PET)/computed tomography (CT) for detecting clinical recurrence after primary treatment for prostate cancer. PATIENTS AND METHODS In all, 50 patients with prostate cancer who had had initial therapy (radical prostatectomy in 40, external beam radiation in three and interstitial brachytherapy in seven) had PET/CT using [11C]-choline in the presence of an increased or increasing prostate-specific antigen (PSA) level. The mean (range) time to biochemical progression was 22 (2,136) months. Current PSA levels were determined in all patients at the time of examination. The results were correlated with the histopathology reports after targeted biopsy or surgery, and with the clinical follow-up. RESULTS The mean (median, range) PSA level in patients with positive PET/CT was 3.62 (2.42, 0.5,13.1) ng/mL, and that in patients with a negative scan was 0.90 (0.95, 0.41,1.40) ng/mL. PET/CT was positive in seven of 13 patients with a PSA level of <1.5 ng/mL, and histology was positive in this group in nine. In 17 patients with PSA levels of 1.5,2.5 ng/mL PET/CT was positive in all and the histology was positive in 13; in 11 men with a PSA level of 2.5,5 ng/mL PET/CT was positive in all 11 and the histology was positive in 10; in nine men with PSA levels of >5 ng/mL PET/CT identified all as positive and the histology was positive in eight. The sensitivity at a PSA level of <2.5 ng/mL of PET/CT for detecting recurrence was 91% (95% confidence interval, 71,99%) with a specificity of 50% (16,84)%. CONCLUSION [11C]-choline PET/CT seems to be useful for re-staging prostate cancer after curative therapy and with increasing PSA levels; this was verified by histological examination. We recommend this method at PSA levels of <2.5 ng/mL. [source] Cancer incidence after localized therapy for prostate cancerCANCER, Issue 5 2006Kihyuck Moon MD Abstract BACKGROUND. Second cancers may occur in patients who have undergone radiation therapy. The risk for these adverse events after therapy is uncertain. In this study, the authors examined the size and significance of the observed association between occurrences of secondary cancers 5 years after radiotherapy in a large population of men with incident prostate cancer. METHODS. Men with incident prostate cancer were identified from the Surveillance, Epidemiology, and End Results (SEER) registry and were distinguished by the type of treatment received, tumor stage, tumor grade, and age at diagnosis. SEER data also were used to identify occurrences of secondary cancer beginning 5 years after the date patients were diagnosed with prostate cancer. Multivariate logistic regression analysis was used to estimate the adjusted odds of the subsequent occurrence of other cancers associated with types of radiation therapy received and was adjusted for the type of surgery, tumor grade, stage, and patient age. RESULTS. Compared with men who received no prostate cancer-directed radiation, men who received external beam radiation therapy (EBRT) as their only form of radiation therapy had statistically significant increased odds of developing secondary cancers at several sites potentially related to radiation therapy, including the bladder (odds ratio [OR], 1.63; 95% confidence interval [95% CI], 1.44,1.84) and rectum (OR, 1.60; 95% CI, 1.29,1.99). Men who received EBRT also had statistically significant higher odds of developing secondary cancers at sites in the upper body and other areas not potentially related to radiation therapy, including the cecum (OR, 1.63; 95% CI, 1.10,1.70), transverse colon (OR, 1.85; 95% CI, 1.30,2.63), brain (OR, 1.83; 95% CI, 1.22,2.75), stomach (OR, 1.38; 95% CI, 1.09,1.75), melanoma (OR, 1.29; 95% CI, 1.09,1.53), and lung and bronchus (OR, 1.25; 95% CI, 1.13,1.37) compared with the odds among men who received no radiation therapy. Men who received radiation therapy in the form of radioactive implants or isotopes, either in isolation or combined with beam radiation, did not have significantly different odds of secondary cancer occurring at any of the 20 most common sites. CONCLUSIONS. Patients who received with EBRT had significantly higher odds of developing second cancers both overall and in the areas that were exposed to radiation. It is noteworthy that, to the authors' knowledge, this report shows for the first time that, despite the higher doses of radiation delivered, patients who received radioactive implants had the lowest odds of developing second cancers. Cancer 2006. © 2006 American Cancer Society. [source] High-dose 131I-metaiodobenzylguanidine therapy for 12 patients with malignant pheochromocytomaCANCER, Issue 2 2003Brian Rose M.D. Abstract BACKGROUND 131I-Metaiodobenzylguanidine (131I-MIBG) can be used systemically to treat malignant pheochromocytoma. To improve outcome, the authors used higher levels of activity of 131I-MIBG than previously reported. The authors reported the response rates and toxicity levels in patients with malignant pheochromocytoma or paraganglioma who were treated with high-dose 131I-MIBG. METHODS Following debulking surgery and stem cell harvest, 12 patients with malignant pheochromocytoma or paraganglioma were treated with 131I-MIBG. Five had received previous external beam radiation and/or chemotherapy. The median single treatment dose was 800 mCi (37 gigabecquerels; range, 386,866 mCi) or 11.5 mCi/kg (range, 5.6,18.3 mCi/kg). The median cumulative dose was 1015 mCi (range, 386,1690 mCi). RESULTS Three patients had a complete response, two of whom had soft tissue and skeletal metastases. Their median follow-up was 45 months (range, 23,101 months). Seven patients had a partial response (PR), with a median follow-up 43 months (range, 6,47 months). Two patients without a response died with progressive disease (PD) and 2 patients with an initial PR died of PD at 13 and 11 months, respectively. Grade 3 thrombocytopenia occurred after 79% (15 of 19) of treatments had been administered. Grade 3 and 4 neutropenia followed 53% (10 of 19) and 19% (4 of 19) of treatments, respectively. One patient required stem cell infusion, and one developed primary ovarian failure. CONCLUSIONS The single and cumulative doses of 131I-MIBG were approximately 2,3.5 times higher than those used at other centers. Unlike previous reports, two patients with both skeletal and soft tissue metastases had a complete response. Hematologic toxicity was significant but tolerable. High-dose 131I-MIBG may lead to long-term survival in patients with malignant pheochromocytoma. Cancer 2003;98:239,48. © 2003 American Cancer Society. DOI 10.1002/cncr.11518 [source] A multiinstitutional, concurrent chemoradiation trial of strontium-89, estramustine, and vinblastine for hormone refractory prostate carcinoma involving boneCANCER, Issue 6 2002Wallace Akerley M.D. Abstract BACKGROUND Estramustine phosphate (EMP) and vinblastine have radiosensitizing properties and significant activity against hormone refractory prostate carcinoma. Strontium-89 is a palliative agent that acts as a selective radiation source for bone metastasis. The combination of EMP, vinblastine, and strontium-89 was developed to exploit the potential for radiosynergy. PATIENTS AND METHODS Forty-four patients at the Brown Oncology Group affiliated hospitals were treated with oral EMP 600 mg/m2 daily on Weeks 1,4 and 7,10, vinblastine 4 mg/m2 intravenously once each week on Weeks 1,4 and 7,10, and strontium-89 2.2 MBq/kg on Day 1. Courses were repeated every 12 weeks. Response assessment was based on a change in the serum prostate specific antigen (PSA) levels, correlated with change in measurable disease and bone scan appearance. RESULTS A greater than or equal to 50% decline in PSA for at least 6 weeks was observed in 21 patients (48%, 95% confidence interval, 33,62%). Median duration of response was 23 weeks (range, 6,70.8 weeks). The median survival was 13 months with 1- and 2-year survival rates of 55% and 25%, respectively. After completion of protocol therapy, a retrospective review showed that only nine patients received subsequent palliative external beam radiation after progression. CONCLUSIONS The addition of strontium-89 to the regimen of EMP and vinblastine can be delivered safely and in repeated doses, provides effective palliation, and may decrease the need for future radiation therapy. A randomized trial is necessary to quantify these effects. Cancer 2002;94:1654,60. © 2002 American Cancer Society. DOI 10.1002/cncr.10437 [source] 4365: The role of transpupillary thermotherapy in combined treatment of retinoblastomaACTA OPHTHALMOLOGICA, Issue 2010SV SAAKYAN Purpose Retinoblastoma (RB) is one of the most serious ophthalmic pathology in childhood. Treatment options that provide eye preservation include chemotherapy, brachytherapy, external beam radiation, cryotherapy and laser treatment. The aim of our study is to evaluate efficiency of transpupillary thermotherapy (TTT) as a part of combined treatment of RB. Methods Our group consists of 30 RB patients (34 eyes). All patients received systemic chemotherapy (Carboplatin and Vincristine). Tumor thickness before TTT varied from 0.9 to 2.6 mm, tumor base diameter varied from 2 to 10 mm. Seven patients had monolateral RB, others had bilateral lesion. Five patients were treated with brachytherapy before TTT. TTT was performed using infrared diode laser Nidec DC 3300. Exposure time was 60 seconds. Width of laser beam was from 1000 to 2000 nm. TTT power setting varied from 600 to 900 mW. Eleven patients had TTT more then once. Follow-up period after TTT was up to 24 months. Results Control examination after TTT showed good response to the treatment in 27 eyes (79.4%). After TTT we saw hyperpigmented scar on the eye fundus at the place of previous tumor location, on OCT it looked like hyper-reflective stripe replacing all layers of a retina. Seven eyes (20.6%) were resistant to TTT, five of them were successfully treated by additional brachytherapy. Two eyes were enucleated because of uncontrolled tumor growth. Evaluation of metastatic disease in all patients revealed no signs of metastasis at the time of treatment or during follow-up. Conclusion TTT can be used in combined treatment of RB for small multifocal lesions. The method is rather simple and uncomplicated. Patients treated with TTT have better visual prognosis in comparison with brachytherapy. [source] Effect of plasma treatment and electron beam radiations on the strength of nanofilled adhesive-bonded jointsPOLYMER ENGINEERING & SCIENCE, Issue 8 2010H.M.S. Iqbal This investigation highlights the adhesion performance of carbon fiber- and glass fiber-reinforced polyphenylene sulfide when joined by high-performance neat epoxy adhesive and nanofilled epoxy adhesive. A significant increase in the surface energy of these materials is observed after the surface modification with atmospheric plasma treatment. An increase in surface roughness is observed after exposing the surface to plasma. Lap shear testing of untreated and plasma-treated joints is carried out to correlate the improvement in adhesion properties with the joint strength. A considerable increase in joint strength is observed when the surfaces of these materials are modified by atmospheric pressure plasma. There is a further increase in joint strength when the composites are joined by nanofilled epoxy adhesive, and subsequent exposure to electron beam radiations results in minor increase in the joint strength. Finally, the fractured surfaces of the joints are examined and the analysis is performed. POLYM. ENG. SCI., 50:1505,1511, 2010. © 2010 Society of Plastics Engineers [source] | ||||||||||