Linacs equipped with flattening filter-free (FFF) megavoltage photon beams are now commercially available. However, the commissioning of FFF beams poses challenges that are not shared with traditional flattened megavoltage X-ray beams. The planning system must model a beam that is peaked in the center and has an energy spectrum that is softer than the flattened beam. Removing the flattening fil...

objective(s): chemoresistance remains the main causes of treatment failure and mortality in cancer patients. there is an urgent need to investigate novel approaches to improve current therapeutic modalities and increase cancer patients' survival. induction of drug efflux due to overexpression of                  p-glycoproteins is considered as an important leading cause of multidrug resis...

background: lung cancer is one of the fatal cancers in iran while 12% of the mortalities are related to this cancer in the country. this active hospital-based study was undertaken to determine the occurrence of lung cancer in fars province, southern iran. methods: data including face-to-face interview with patients and a survey of their medical and demographic records in relation to all invasiv...

cisplatin-based chemotherapy is the standard treatment for advanced non-small cell lung cancer (nsclc). many novel drugs have been used in combination with cisplatin in this setting. of these drugs, gemcitabine is reported to have a high response rate and acceptable toxicity. the aim of this study was to evaluate the efficacy and safety of gemcitabine and cisplatin combination. twentythree pati...

background lung cancer is one of the most common causes of death worldwide. although smoking and environmental pollutants are the most important risk factors of lung cancer, the role of infectious causes should also be considered in the pathogenesis and progress of lung cancer. objectives this study examined the relationship between helicobacter pylori and lung cancer through serology, real-tim...

background: epidemiological studies have probed the correlation between telomere length and the risk of lung cancer, but their findings are inconsistent in this regard.  the present meta-analysis study has been carried out to demonstrate the association between relative telomere length in peripheral blood leukocytes and the risk of lung cancer using an established q-pcr technique. methods: a sy...

background: lung cancer is considered as one of the most frequent cancers worldwide, and has been the cause of more than onemillion mortalities each year. exposure to tobacco smoke is the primary cause of most lung cancers, since it contains several thousandcompounds, including more than 50 known carcinogens. however, a small fraction of individuals who are exposed to tobacco smokedevelop lung ...

Most of the treatment units, both new and old models, are equipped with a megavoltage portal imager but its use for volumetric imaging is limited. This is mainly due to the poor image quality produced by the high-energy treatment beam (> 6MV). A linac at our center is equipped with a prototype 2.5 MV imaging beam. This study evaluates the feasibility of low-dose megavoltage cone-beam imaging wi...

normal 0 false false false en-us x-none ar-sa microsoftinternetexplorer4 background : lung cancer has remained the most prevalent malignancy worldwide. it is the fifth leading cause of cancer death in iran. nevertheless, during last few years a gradual permanent increase in its incidence has been reported. although the crucial role of tobacco smoke in lung cancer initiation has long been establ...