41 research outputs found

    Breathing adapted radiotherapy: a 4D gating software for lung cancer

    Get PDF
    <p>Abstract</p> <p>Purpose</p> <p>Physiological respiratory motion of tumors growing in the lung can be corrected with respiratory gating when treated with radiotherapy (RT). The optimal respiratory phase for beam-on may be assessed with a respiratory phase optimizer (RPO), a 4D image processing software developed with this purpose.</p> <p>Methods and Materials</p> <p>Fourteen patients with lung cancer were included in the study. Every patient underwent a 4D-CT providing ten datasets of ten phases of the respiratory cycle (0-100% of the cycle). We defined two morphological parameters for comparison of 4D-CT images in different respiratory phases: tumor-volume to lung-volume ratio and tumor-to-spinal cord distance. The RPO automatized the calculations (200 per patient) of these parameters for each phase of the respiratory cycle allowing to determine the optimal interval for RT.</p> <p>Results</p> <p>Lower lobe lung tumors not attached to the diaphragm presented with the largest motion with breathing. Maximum inspiration was considered the optimal phase for treatment in 4 patients (28.6%). In 7 patients (50%), however, the RPO showed a most favorable volumetric and spatial configuration in phases other than maximum inspiration. In 2 cases (14.4%) the RPO showed no benefit from gating. This tool was not conclusive in only one case.</p> <p>Conclusions</p> <p>The RPO software presented in this study can help to determine the optimal respiratory phase for gated RT based on a few simple morphological parameters. Easy to apply in daily routine, it may be a useful tool for selecting patients who might benefit from breathing adapted RT.</p

    Alcohol use as a risk factor for tuberculosis – a systematic review

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>It has long been evident that there is an association between alcohol use and risk of tuberculosis. It has not been established to what extent this association is confounded by social and other factors related to alcohol use. Nor has the strength of the association been established. The objective of this study was to systematically review the available evidence on the association between alcohol use and the risk of tuberculosis.</p> <p>Methods</p> <p>Based on a systematic literature review, we identified 3 cohort and 18 case control studies. These were further categorized according to definition of exposure, type of tuberculosis used as study outcome, and confounders controlled for. Pooled effect sizes were obtained for each sub-category of studies.</p> <p>Results</p> <p>The pooled relative risk across all studies that used an exposure cut-off level set at 40 g alcohol per day or above, or defined exposure as a clinical diagnosis of an alcohol use disorder, was 3.50 (95% CI: 2.01–5.93). After exclusion of small studies, because of suspected publication bias, the pooled relative risk was 2.94 (95% CI: 1.89–4.59). Subgroup analyses of studies that had controlled for various sets of confounders did not give significantly different results and did not explain the significant heterogeneity that was found across the studies.</p> <p>Conclusion</p> <p>The risk of active tuberculosis is substantially elevated in people who drink more than 40 g alcohol per day, and/or have an alcohol use disorder. This may be due to both increased risk of infection related to specific social mixing patterns associated with alcohol use, as well as influence on the immune system of alcohol itself and of alcohol related conditions.</p

    Neoadjuvant chemoradiation followed by surgery versus surgery alone for patients with adenocarcinoma or squamous cell carcinoma of the esophagus (CROSS)

    Get PDF
    textabstractBackground. A surgical resection is currently the preferred treatment for esophageal cancer if the tumor is considered to be resectable without evidence of distant metastases (cT1-3 N0-1 M0). A high percentage of irradical resections is reported in studies using neoadjuvant chemotherapy followed by surgery versus surgery alone and in trials in which patients are treated with surgery alone. Improvement of locoregional control by using neoadjuvant chemoradiotherapy might therefore improve the prognosis in these patients. We previously reported that after neoadjuvant chemoradiotherapy with weekly administrations of Carboplatin and Paclitaxel combined with concurrent radiotherapy nearly always a complete R0-resection could be performed. The concept that this neoadjuvant chemoradiotherapy regimen improves overall survival has, however, to be proven in a randomized phase III trial. Methods/design. The CROSS trial is a multicenter, randomized phase III, clinical trial. The study compares neoadjuvant chemoradiotherapy followed by surgery with surgery alone in patients with potentially curable esophageal cancer, with inclusion of 175 patients per arm. The objectives of the CROSS trial are to compare median survival rates and quality of life (before, during and after treatment), pathological responses, progression free survival, the number of R0 resections, treatment toxicity and costs between patients treated with neoadjuvant chemoradiotherapy followed by surgery with surgery alone for surgically resectable esophageal adenocarcinoma or squamous cell carcinoma. Over a 5 week period concurrent chemoradiotherapy will be applied on an outpatient basis. Paclitaxel (50 mg/m2) and Carboplatin (Area-Under-Curve = 2) are administered by i.v. infusion on days 1, 8, 15, 22, and 29. External beam radiation with a total dose of 41.4 Gy is given in 23 fractions of 1.8 Gy, 5 fractions a week. After completion of the protocol, patients will be followed up every 3 months for the first year, every 6 months for the second year, and then at the end of each year until 5 years after treatment. Quality of life questionnaires will be filled out during the first year of follow-up. Discussion. This study will contribute to the evidence on any benefits of neoadjuvant treatment in esophageal cancer patients using a promising chemoradiotherapy regimen. Trial registration. ISRCTN80832026
    corecore