However, so far only 10 to 15 percent of lung cancer patients can be cured permanently. More than half of the patients with a small-cell lung carcinoma and about 65 percent of the patients with a non-small-cell lung carcinoma receive radiation treatment in the course of their illness.
The precision of a three-dimensional radiation planning is, however, limited by nature in the case of lung cancer: During breathing, the tumors shift by a few centimeters. As a consequence, the target area "moves" and can be missed if the radiation limits have been chosen too narrowly. Then the tumor cells will keep growing. But if the radiotherapist chooses the limits of the radiation field too generously, more side effects in the healthy lung are to be expected.
Image guided radiotherapy.
The image guided radiotherapy (IGRT) offers a solution to this dilemma, as experts report at the ESTRO congress in Leipzig. Novel linear accelerators that are equipped with a special x-ray device depict the tumor immediately before the radiation treatment. This allows capturing "moving" target areas. The device registers whether the planned situation matches the real situation. If this is not the case, the computer calculates the deviation, and the radiation table is shifted accordingly.
The respiration-adapted radiotherapy is also promising. With this method, the radiation is activated and deactivated with the breathing. In this way, the rays always hit the tumor at the same position. In some cases, the patients are also asked to hold their breath or to breathe in a certain rhythm, which requires training the patients accordingly at the beginning of the treatment. If the anatomical shifts can be purposefully controlled, they can also be purposefully compensated for. This method is also systematically studied at the moment. Here, physicians and physicists mainly calculate how the radiation volume can be decreased by this technique.
Stereotactic radiotherapy takes the place of the scalpel.
Stereotactic radiation, which requires a lot of effort and is so far mostly used for brain tumors, is now also tested by radiotherapists on small tumors of the body stem in especially radiosensitive environments. The exact three-dimensional coordinates of the target area are determined with computer tomograms and a special planning system. To enable a precise transmission of the planned radiation data, the body of the patient is fixated with a frame during the treatment. Under computer-tomographic guidance, markings in this frame are used to direct the radiation precisely at the tumor. In most cases, this is achieved by having the radiation hit the target location from many different directions and at precisely calculated angles.
A team led by Frank Zimmermann from the Klinikum rechts der Isar in Munich presents a study with 68 patients in Leipzig, whose small lung tumors could not be operated on for general health reasons. In 3 to 5 sessions, a high radiation dose was in each case delivered by stereotactic methods. In the so far three-year follow-up period, the tumor resumed its growth in only four patients (6 percent). No serious adverse effects were observed.
Barbara Ritzert | alfa
Routing gene therapy directly into the brain
07.12.2017 | Boston Children's Hospital
New Hope for Cancer Therapies: Targeted Monitoring may help Improve Tumor Treatment
01.12.2017 | Berliner Institut für Gesundheitsforschung / Berlin Institute of Health (BIH)
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong
Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...
An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications
Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...
Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.
The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...
Transistors based on carbon nanostructures: what sounds like a futuristic dream could be reality in just a few years' time. An international research team working with Empa has now succeeded in producing nanotransistors from graphene ribbons that are only a few atoms wide, as reported in the current issue of the trade journal "Nature Communications."
Graphene ribbons that are only a few atoms wide, so-called graphene nanoribbons, have special electrical properties that make them promising candidates for the...
08.12.2017 | Event News
07.12.2017 | Event News
05.12.2017 | Event News
08.12.2017 | Life Sciences
08.12.2017 | Information Technology
08.12.2017 | Information Technology