1,720,963 research outputs found
Natriumbutyrat-Einlaufe in der Behandlung der akuten radiotherapieinduzierten Proktitis bei Patienten mit Prostatakarzinom und der Einfluss auf eine spate Proktitis. Eine prospektive Untersuchung
No full textTo evaluate prospectively the effect of sodium butyrate enemas on the treatment of acute and the potential influence on late radiation-induced proctitis. 31 patients had been treated with sodium butyrate enemas for radiation-induced acute grade II proctitis which had developed after 40 Gy in median. During irradiation the toxicity was evaluated weekly by the Common Toxicity Criteria (CTC) and subsequently yearly by the RTOG (Radiation Therapy Oncology Group) and LENT-SOMA scale. 23 of 31 patients (74%) experienced a decrease of CTC grade within 8 days on median. A statistical significant difference between the incidence and the severity of proctitis before start of treatment with sodium butyrate enemas compared to 14 days later and compared to the end of irradiation treatment course, respectively, was found. The median follow-up was 50 months. Twenty patients were recorded as suffering from no late proctitis symptom. Eleven patients suffered from grade I and 2 of these patients from grade II toxicity, too. No correlation was seen between the efficacy of butyrate enemas on acute proctitis and prevention or development of late toxicity, respectively. Sodium butyrate enemas are effective in the treatment of acute radiation-induced proctitis in patients with prostate cancer but have no impact on the incidence and severity of late proctitis
A prospective study of faecal calprotectin and lactoferrin in the monitoring of acute radiation proctitis in prostate cancer treatment
No full textObjective. Acute radiation proctitis is a relevant complication of pelvic radiation. The purpose of this study was to investigate two markers of gut inflammation as non-invasive diagnostic tools to evaluate acute radiation proctitis. Material and methods. Twenty patients who underwent radiotherapy for prostate cancer took part in this prospective study. Radiation-induced toxicity was evaluated weekly during radiotherapy in compliance with the CTC toxicity criteria. Stool samples from patients were examined before treatment, weekly during radiotherapy and 2 weeks after the end of radiotherapy using enzyme-linked immunosorbent assay for calprotectin and lactoferrin and correlated with the CTC toxicity. Results. Calprotectin and lactoferrin faecal values increased significantly during radiation treatment and decreased about 2 weeks after cessation of radiation. Faecal concentrations of calprotectin and lactoferrin correlated with the documented radiation proctitis symptoms (all grades together) in 15/20 patients (75%). With respect to changes in faecal concentrations and correspondence to proctitis symptoms, both markers showed parallel results in 90% of the patients. On comparing calprotectin and lactoferrin concentrations between the 4th week of radiation and the 1st week, it was found that patients with any grade of toxicity exhibited a significantly higher increase in calprotectin (p = 0.044) and lactoferrin (p = 0.05), respectively, compared with those without toxicity. Conclusions. Calprotectin and lactoferrin faecal values changed during radiation treatment and after cessation of radiation, with correlation to acute proctitis symptoms in most of the patients. Before markers are used to monitor acute radiation proctitis, further experience should be acquired. Patients will be followed to determine the predictive value of the two tested markers for chronic radiation proctitis
The Impact of Prostate Volume Changes during External-Beam Irradiation in Consequence of HDR Brachytherapy in Prostate Cancer Treatment
No full textPurpose: To evaluate prostate volume changes during external-beam irradiation in consequence of high-dose-rate (HDR) brachytherapy in prostate cancer treatment. Patients and Methods: 20 patients who underwent radiotherapy for prostate cancer were included in this prospective evaluation. All patients had a computed tomography (CT) scan for planning of the external-beam irradiation and additional scans after each HDR brachytherapy. For the planning target volume (PTV), a safety margin of 10 mm was added to the clinical target volume (CTV) in each direction. The prostate volume measured in the planning CT was compared with the prostate volumes measured after HDR brachytherapy and, subsequently, the change of prostate volume was calculated. Volume changes which resulted in differences of the prostate radius of > 5 mm for the CTV were defined as a reason for a new treatment-planning procedure for the patient. Results: Taking all patients together, prostate volumes before HDR, 1 day and 4-6 days after the first HDR treatment, as well as 1 day and 4-6 days after the second HDR treatment were in median 37.7 cm(3), 37.6 cm(3), 38.2 cm(3), 39.3 cm(3), and 40.5 cm(3), respectively. In none of the patient, a volume change resulted in a change of the prostate radius of > 5 mm for the CTV. Prerequisite for this calculation was the simplification of the complex prostate geometry to a sphere. No new treatment-planning procedure was necessary during external-beam radiotherapy. Conclusion: HDR brachytherapy does change the prostate volume. Under the condition of a 10-mm safety margin in each direction added to the CTV for the PTV, no new treatment-planning procedure was necessary after HDR brachytherapy. There is no need for CT scans at regular intervals during external-beam radiotherapy
Effect of a Prostaglandin - Given Rectally for Prevention of Radiation-Induced Acute Proctitis - on Late Rectal Toxicity Results of a Phase III Randomized, Placebo-Controlled, Double-Blind Study
No full textBackground and Purpose: To assess the Late effect of a prostaglandin, given rectally during irradiation, on Late rectal toxicity. In the acute treatment setting no significant differences in reducing the incidence of acute proctitis symptoms in patients receiving misoprostol, however, significantly more rectal bleeding had been reported. Patients and Methods: A total of 100 patients who had undergone radiotherapy for prostate cancer had been entered into this phase III randomized, placebo-controlled, double-blind study with misoprostol or placebo suppositories. The toxicity was evaluated yearly after cessation of irradiation by the RTOG/LENT-SOMA scale. Results: The median follow-up was 50 months. 20 patients suffered from grade 1, four patients from grade 2 as well, and three patients only from grade 2 toxicity. Frequency, bleeding and urgency were the most commonly reported symptoms. In keeping with other studies and clinical experience, the symptoms peaked within the first 2 years with a median for grade 1 of 13 months and for grade 2 of 15 months. The presence of acute toxicity grade 2 showed a correlation with the development of any late toxicity (p = 0.03). Any acute rectal bleeding was significant correlated with any late rectal bleeding (p = 0.017). Conclusion: Misoprostol given as once-daily suppository for prevention of acute radiation-induced proctitis does neither influence the incidence and severity of radiation-induced acute nor Late rectal toxicity. Misoprostol has no negative impact on the incidence and severity of late rectal bleeding, in contrast to acute rectal bleeding. The routine clinical use of misoprostol suppositories cannot be recommended
Gold marker displacement due to needle insertion during HDR-brachytherapy for treatment of prostate cancer: a prospective cone beam computed tomography and kilovoltage on-board imaging (kV-OBI) study
No full textPurpose: To evaluate gold marker displacement due to needle insertion during HDR-brachytherapy for therapy of prostate cancer. Patients and methods: 18 patients entered into this prospective evaluation. Three gold markers were implanted into the prostate during the first HDR-brachytherapy procedure after the irradiation was administered. Three days after marker implantation all patients had a CT-scan for planning purpose of the percutaneous irradiation. Marker localization was defined on the digitally-reconstructed-radiographs (DRR) for daily (VMAT technique) or weekly (IMRT) set-up error correction. Percutaneous therapy started one week after first HDR-brachytherapy. After the second HDR-brachytherapy, two weeks after first HDR-brachtherapy, a cone-beam CT-scan was done to evaluate marker displacement due to needle insertion. In case of marker displacement, the actual positions of the gold markers were adjusted on the DRR. Results: The value of the gold marker displacement due to the second HDR-brachytherapy was analyzed in all patients and for each gold marker by comparison of the marker positions in the prostate after soft tissue registration of the prostate of the CT-scans prior the first and second HDR-brachytherapy. The maximum deviation was 5 mm, 7 mm and 12 mm for the anterior-posterior, lateral and superior-inferior direction. At least one marker in each patient showed a significant displacement and therefore new marker positions were adjusted on the DRRs for the ongoing percutaneous therapy. Conclusions: Needle insertion in the prostate due to HDR-brachytherapy can lead to gold marker displacements. Therefore, it is necessary to verify the actual position of markers after the second HDR-brachytherapy. In case of significant deviations, a new DRR with the adjusted marker positions should be generated for precise positioning during the ongoing percutaneous irradiation.Open-Access-Publikationsfonds 201
Faecal calprotectin and lactoferrin values during irradiation of prostate cancer correlate with chronic radiation proctitis: Results of a prospective study
No full textObjective. Acute proctitis and chronic radiation proctitis are relevant complications of pelvic radiation. The purpose of this study was to investigate two markers of gut inflammation during and after irradiation for prostate cancer to evaluate a correlation between acute and chronic proctitis. Material and methods. Two patient groups were analysed. In group 1, stool samples from 20 patients were collected before therapy, every week during therapy, at the end of therapy, and 13 and 27 months after therapy. Group 2 comprised 47 patients who had undergone irradiation 40 months earlier. Toxicity was determined by common toxicity criteria (CTC) and the LENT soma scale. Calprotectin and lactoferrin values were determined by ELISA. Results. In group 1, acute values for both faecal markers were significantly correlated with chronic proctitis symptoms and all patients with chronic toxicity had acute proctitis symptoms with elevated faecal values. In group 2, where stool samples were solely collected 40 months after irradiation, the Pearson square test showed both a significant correlation between calprotectin and lactoferrin values and toxicity after 40 months. Conclusions. Within a group of 19 patients followed for two years after irradiation for prostate cancer, and 47 patients tested 40 months after irradiation, increased faecal values of calprotectin and lactoferrin were significantly correlated with the occurrence of chronic proctitis. This observation should be confirmed in an expanded study
High-Grade Acute Organ Toxicity During Preoperative Radiochemotherapy as Positive Predictor for Complete Histopathologic Tumor Regression in Multimodal Treatment of Locally Advanced Rectal Cancer
No full textPurpose: To test for a possible correlation between high-grade acute organ toxicity during preoperative radiochemotherapy and complete tumor regression after total mesorectal excision in multimodal treatment of Locally advanced rectal cancer. Patients and Methods: From 2001 to 2008, 120 patients were treated. Preoperative treatment consisted of normofractionated radiotherapy at a total dose of 50.4 Gy, and either two cycles of 5-fluorouracil (5-FU) or two cycles of 5-FU and oxaliplatin. Toxicity during treatment was monitored weekly, and any toxicity CTC (Common Toxicity Criteria) grade 2 of enteritis, proctitis or cystitis was assessed as high-grade organ toxicity for later analysis. Complete histopathologic tumor regression (TRG4) was defined as the absence of any viable tumor cells. Results: A significant coherency between high-grade acute organ toxicity and complete histopathologic tumor regression was found, which was independent of other factors Like the preoperative chemotherapy schedule. The probability of patients with acute organ toxicity >= grade 2 to achieve TRG4 after neoadjuvant treatment was more than three times higher than for patients without toxicity (odds ratio: 3.29, 95% confidence interval: [1.01, 10.96]). Conclusion: Acute organ toxicity during preoperative radiochemotherapy in rectal cancer could be an early predictor of treatment response in terms of complete tumor regression. Its possible impact on local control and survival is under further prospective evaluation by the authors' working group.German Research Foundation (DFG) [KFO 179
KRAS and BRAF mutations in patients with rectal cancer treated with preoperative chemoradiotherapy
No full textBackground and purpose: KRAS and BRAF are Mutated in 35% and 10% of colorectal cancers, respectively. However, data specifically for locally advanced rectal cancers are scarce, and the frequency of KRAS mutations in codons 61 and 146 remains to be established. Materials and methods: DNA was isolated from pre-therapeutic biopsies of 94 patients who were treated within two phase-III clinical trials receiving preoperative chemoradiotherapy. Mutation status of KRAS exons 1-3 and BRAF exon 15 was established using the ABI PRISM Big Dye Sequencing Kit and subsequently correlated with clinical parameters. Results: Overall, KRAS was Mutated in 45 patients (48%). Twenty-nine mutations (64%) were located in codon 12, 10 mutations (22%) in codon 13, and 3 mutations (7%) in codons 61 and 146. No V600E BRAF mutation was detected. The presence of KRAS mutations was Correlated neither with tumor response or lymph node Status after preoperative chemoradiotherapy nor with overall Survival or disease-free survival. When KRAS exon I mutations were separated based on the amino-acid exchange, we again failed to detect significant correlations (p = 0.052), However, G12V Mutations appeared to be associated with higher rates Of tumor regression than G13D mutations (p = 0.012). Conclusion: We are the first to report the mutation status of KRAS and BRAF in pre-therapeutic biopsies from locally advanced rectal cancers. The high number of KRAS mutations in codons 61 and 146 emphasizes the importance to expand current mutation analyses, whereas BRAF mutations are not relevant for rectal carcinogenesis. Although the KRAS Mutation Status Was not Correlated with response, the Subtle difference between G12V and G13D mutations warrants analysis of a larger patient population. (C) 2009 Elsevier Ireland Ltd. All rights reserved, Radiotherapy arid Oncology 94 (2010) 76-81Deutsche Forschungsgemeinschaft [KFO 179
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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