Intracranial radiosurgery in the Netherlands. A planning comparison of available systems with regard to physical aspects and workload.

Different planning and treatment systems for intracranial stereotactic radiosurgery available in the Netherlands are compared. The systems for intracranial radiosurgery include: Gamma Knife, Cyberknife, Novalis, and Tomotherapy. Electronic data of 5 patients was transferred to all participating centres and treatment plans were generated according to 2 different prescription protocols. For this study, plans were also generated for a conventional linac. Even systems with a high resolution (Gammaknife and Novalis) have conformity indices in violation with RTOG guidelines (CI > 2.5) when target volumes of <0.5 cc are treated. For medium sized targets (0.5-1 cc) all systems performed reasonably well, but for the different systems a large range of conformity indices was seen (1.1 to 3.7). The differences are partly system dependent but depend also on specific planning choices made. For larger target volumes (> 1 cc), all systems perform well. The workload of the different techniques was comparable although the treatment times were usually longer for Gamma Knife radiosurgery. We conclude that small targets should be treated by dedicated systems, larger volumes (> 0.5-1 cc) can also be treated using conventional treatment systems equipped with a MLC.

[Treatment of patients with stage III non-small cell lung cancer: concurrent high-dose chemotherapy and radiotherapy]. / Behandeling van patiënten met niet-kleincellig longcarcinoom stadium III: gelijktijdig hooggedoseerde chemotherapie en radiotherapie.

The treatment of patients with locally advanced non-small cell lung cancer (stage III) has changed significantly in the past few years. Patients with a non-resectable stage IIIA/B tumour are given combined treatment consisting ofchemotherapy and radiotherapy. These can be administered sequentially or concurrently. It has been shown recently that concurrent chemoradiotherapy gives a survival advantage in comparison with sequential chemoradiotherapy. Cisplatin and etoposide are usually the drugs of choice for chemotherapy in patients with stage III cancer. A biologically effective dose of radiotherapy equivalent to 60-66 Gy, over a maximum of 6.5 weeks, should be given. Surgery is possible for a selected group of patients, provided a complete objective mediastinal response has been achieved after chemoradiotherapy and a complete resection appears to be technically feasible. It is recommended to apply this treatment in a research setting. High-dose concurrent chemoradiotherapy is advised as the standard treatment for stage III non-small cell lung cancer in patients in good physical condition.