Search results for "RADIATION"
showing 10 items of 5298 documents
44Sc-DOTA-BN[2-14]NH2 in comparison to 68Ga-DOTA-BN[2-14]NH2 in pre-clinical investigation. Is 44Sc a potential radionuclide for PET?
2011
In the present study we demonstrate the in vitro and in vivo comparison of the (44)Sc and (68)Ga labeled DOTA-BN[2-14]NH(2). (44)Sc is a positron emitter with a half life of 3.92 h. Hence it could be used for PET imaging with ligands requiring longer observation time than in the case of (68)Ga.The binding affinity of (nat)Sc-DOTA-BN[2-14]NH(2) and (nat)Ga-DOTA-BN[2-14]NH(2) to GRP receptors was studied in competition to [(125)I-Tyr(4)]-Bombesin in the human prostate cancer cell line PC-3. A preliminary biodistribution in normal rats was performed, while first microPET images were assessed in male Copenhagen rats bearing the androgen-independent Dunning R-3327-AT-1 prostate cancer tumor.The …
Comparison between MRI and pathology in the assessment of tumour regression grade in rectal cancer
2017
Background: Limited data exist regarding the correlation between MRI tumour regression grade (mrTRG) and pathological TRG (pTRG) in rectal cancer. Methods: mrTRG and pTRG were compared in rectal cancer patients from two phase II trials (EXPERT and EXPERT-C). The agreement between radiologist and pathologist was assessed with the weighted κ test while the Kaplan–Meier method was used to estimate survival outcomes. Results: One hundred ninety-one patients were included. Median time from completion of neoadjuvant treatment to pre-operative MRI and surgery was 4.1 weeks (interquartile range (IQR): 3.7–4.7) and 6.6 weeks (IQR: 5.9–7.6), respectively. Fair agreement was found between mrTRG and pT…
Quantitative changes of metabolic and bioenergetic parameters in experimental tumors during fractionated irradiation.
1999
Abstract Purpose: Previous studies with rat rhabdomyosarcomas indicate that during fractionated irradiation profound alterations of the tumor microvasculature and the oxygenation status occur when the total dose exceeds 45 Gy. At this dose a destruction which included all structures of the vessels and a significant worsening in tumor oxygenation were found. The aim of the present study was to analyze whether these effects of fractionated irradiation on the microvasculature and on tumor oxygenation also induce changes in the bioenergetic and metabolic status in the tumors during radiation treatment. Methods and Materials: R1H rhabdomyosarcomas of the rat implanted into the flank were irradia…
Residential magnetic fields as a risk factor for childhood acute leukaemia: Results from a German population-based case-control study
2001
Our objective was to investigate whether exposure to residential power-frequency (50 Hz) magnetic fields above 0.2 μT increases a child's risk of leukaemia and to confirm or reject a finding from a previous German study on this topic, which reported increased leukaemia risk with exposure to stronger magnetic fields during the night. A population-based case-control study was used, covering the whole of the former West Germany. Residential magnetic fields were measured over 24 hr for 514 children with acute leukaemia identified by the German Childhood Cancer Registry and 1,301 control children taken from population registration files. Magnetic fields above 0.2 μT were relatively rare in Germa…
Optimal local control and tolerability of three-dimensional conformal radiation therapy in prostate cancer: A single institutional experience of dose…
2013
Aims To evaluate long-term late side effects, clinical and biochemical relapse in non-metastatic prostate cancer patients treated with dose escalation, from 74 to 78 Gy, by means of three dimensional conformal radiation therapy. Materials and Methods Clinical data of 125 patients with prostate cancer who underwent three-dimensional conformal radiation therapy were retrospectively evaluated. All patients were stratified, according to the NCCN classification, in low, intermediate and high risk, and all of them showed histologically proven adenocarcinoma stage T1–T3 with at least 2 years of follow-up. Late toxicity was analyzed using a modified Radiation Therapy Oncology Group toxicity scale. …
Sequential boost in neoadjuvant irradiation for T3N0-1 rectal cancer: long-term results from a single-center experience.
2016
Purpose To evaluate the influence of radiation dose on tumor regression grade (TRG) and sphincter preservation rate in a series of cT3N0-1 rectal cancer patients treated with neoadjuvant chemoradiotherapy (CT-RT) with or without a sequential radiation boost. Materials and methods Between May 2002 and September 2013, 116 cases were eligible for retrospective evaluation. Radiotherapy was delivered for a total dose of 45 Gy (no boost arm) or 50.4 Gy (boost arm). TRG was evaluated with the Dworak scale. Results Median follow-up was 62 months (range, 12-138 months). The 5-year overall survival and local control rates were 72% and 93%, respectively. Fifty-five patients (47%) were treated with a s…
Prospective randomised trial of chemotherapy given before radiotherapy in childhood medulloblastoma. International society of paediatric oncology (SI…
1995
In a multicentre randomised clinical trial 364 children with biopsy proven medulloblastoma were randomly assigned to receive or not pre-radiotherapy chemotherapy. Children with total or subtotal removal of the tumour, no evidence of invasive brain stem involvement, and no evidence of metastatic disease either within or without the cranium were designated "low risk", those with gross residual tumour, evidence of invasive brain stem involvement or metastases in the central nervous system were designated "high risk". All children were prescribed 55 Gy to the tumour bearing area. "Low risk" children could be randomised to "standard" radiotherapy 35 Gy to the craniospinal axis or "reduced" dose …
Enhanced radiosensitivity in experimental tumours following erythropoietin treatment of chemotherapy-induced anaemia.
1998
The radiosensitivity of solid tumours in anaemic rats treated with recombinant human erythropoietin (rhEPO, epoetin beta) was studied. Anaemia was induced by a single dose of carboplatin (45 mg kg(-1) i.v.), resulting in a reduction in the haemoglobin concentration by 30%. In a second group, the development of anaemia was prevented by rhEPO (1000 IU kg(-1)) administered s.c. three times per week starting 6 days before the carboplatin application. Three days after carboplatin treatment, DS-sarcomas were implanted subcutaneously onto the hind foot dorsum. Neither carboplatin nor rhEPO treatment influenced tumour growth rate. Five days after implantation, tumours were irradiated with a single …
Postoperative Radiation Therapy in Patients with Extracranial Chondrosarcoma: A Joint Study of the French Sarcoma Group and Rare Cancer Network
2020
International audience; PurposePostoperative radiation therapy (poRT) of intracranial/skull base chondrosarcomas (CHSs) is standard treatment. However, consensus is lacking for poRT in extracranial CHS (eCHS) owing to their easier resectability and intrinsic radioresistance. We assessed the practice and efficacy of poRT in eCHS.Methods and MaterialsThis multicentric retrospective study of the French Sarcoma Group/Rare Cancer Network included patients with eCHS who were operated on between 1985 and 2015. Inverse propensity score weighting (IPTW) was used to minimize poRT allocation biases.ResultsOf 182 patients, 60.4% had bone and 39.6% had soft-tissue eCHS. eCHS were of conventional (31.9%)…
High-dose folinic acid and 5-fluorouracil plus cisplatin on a weekly schedule in the treatment of advanced cancer of the head and neck
1992
A group of 60 patients with advanced head/neck cancer were treated with high-dose folinic acid (500 mg/m-2/week-1) plus 5-fluorouracil (400 mg/m-2/week-1 on day 1, and cisplatin (20 mg/m-2/week-1) 24 h after folinic acid infusion was completed. Out of 55 evaluable patients, 10 patients (18%) experienced a complete response with a mean duration of 11.4+ months, 25 patients had a partial response (45%) of 6.7+ months, 6 patients (11%) showed a stabilization of 4.8+ months, and 14 (25%) progressed. The overall response rate was 63.6% (95% confidence limits 56.5%-69.5%). Patients pretreated with radiotherapy had a 67% overall response rate, while those pretreated with chemotherapy showed a 54% …