Radiation Treatment Improvements

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Lung Cancer: New Techniques Improve Radiation Therapy

Posted on : Wed, 11 Oct 2006 08:00:00 GMT | Author : ProScience Communications

News Category : PressRelease

LEIPZIG, Germany, October 11 /PRNewswire/ -- New radiotherapeutic techniques and radiation systems improve theradiotherapy for lung cancer. At the 25th Annual Congress of the EuropeanSociety for Therapeutic Radiology and Oncology (ESTRO), radiooncologistspresent, among others, new possibilities of respiration-controlledradiotherapy.

Lung cancer is the second most common malignant tumour in men afterprostate carcinoma; in Germany alone, about 27,000 men develop the diseaseevery year. But the incidence of lung tumours is increasing in women, too.However, so far only 10 to 15 per cent of lung cancer patients can be curedpermanently. More than half of the patients with a small-cell lung carcinomaand about 65 per cent of the patients with a non-small-cell lung carcinomareceive 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 tumoursshift by a few centimetres. As a consequence, the target area "moves" and canbe missed if the radiation limits have been chosen too narrowly. Then thetumour cells will keep growing. But if the radiotherapist chooses the limitsof the radiation field too generously, more side effects in the healthy lungare 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 acceleratorsthat are equipped with a special x-ray device depict the tumour immediatelybefore the radiation treatment. This allows capturing "moving" target areas.The device registers whether the planned situation matches the realsituation. If this is not the case, the computer calculates the deviation,and the radiation table is shifted accordingly.

Respiration-Adapted Radiotherapy

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 tumour at the same position. In some cases, thepatients are also asked to hold their breath or to breathe in a certainrhythm, which requires training the patients accordingly at the beginning ofthe treatment. If the anatomical shifts can be purposefully controlled, theycan also be purposefully compensated for. This method is also systematicallystudied at the moment. Here, physicians and physicists mainly calculate howthe 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 farmostly used for brain tumours, is now also tested by radiotherapists on smalltumours of the body stem in especially radiosensitive environments. The exactthree-dimensional coordinates of the target area are determined with computertomograms and a special planning system. To enable a precise transmission ofthe planned radiation data, the body of the patient is fixated with a frameduring the treatment. Under computer-tomographic guidance, markings in thisframe are used to direct the radiation precisely at the tumour. In most cases,this is achieved by having the radiation hit the target location from manydifferent directions and at precisely calculated angles.

A team led by Frank Zimmermann from the Klinikum rechts der Isar inMunich presents a study with 68 patients in Leipzig, whose small lung tumourscould not be operated on for general health reasons. In 3 to 5 sessions, ahigh radiation dose was in each case delivered by stereotactic methods. Inthe so far three-year follow-up period, the tumour resumed its growth in onlyfour patients (6 per cent). No serious adverse effects were observed.

Press contact: Prof. Dr. med. Marie-Luise Sautter-Bihl Director of the Clinic for Radiotherapy Municipal Clinic Karlsruhe Moltkestr. 90 76133 Karlsruhe strahlentherapie@klinikum-karlsruhe.de During the conference: Press office in Room B3, Level 0 of the Congress Center Phone: +49-341-4145-5511 ProScience Communications Barbara Ritzert Andechser Weg 17 82343 Pöcking Phone: +49-8157-9397-0 ritzert@proscience-com.de

ProScience Communications

Press contact: Prof. Dr. med. Marie-Luise Sautter-Bihl, Director of the Clinic for Radiotherapy, Municipal Clinic Karlsruhe, strahlentherapie@klinikum-karlsruhe.de. During the conference: Press office in Room B3, Level 0 of the Congress Center, Phone: +49-341-4145-5511, ProScience Communications, Barbara Ritzert, Phone: +49-8157-9397-0, ritzert@proscience-com.de