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Background: No standard treatment for locally advanced pancreatic cancer (LAPC) is defined. Patients and methods Within a multi-centre, randomised phase II trial, 95 patients with LAPC were assigned to three different chemoradiotherapy (CRT) regimens: patients received conventionally fractionated radiotherapy of 50 Gy and were randomised to concurrent 5-fluorouracil (350 mg m−2 per day on each day of radiotherapy, RT-5-FU arm), concurrent gemcitabine (300 mg m−2), and cisplatin (30 mg m−2) on days 1, 8, 22, and 29 (RT-GC arm), or the same concurrent treatment followed by sequential full-dose gemcitabine (1000 mg m−2) and cisplatin (50 mg m−2) every 2 weeks (RT-GC+GC arm). Primary end point was the overall survival (OS) rate after 9 months. Results: The 9-month OS rate was 58% in the RT-5-FU arm, 52% in the RT-GC arm, and 45% in the RT-GC+GC arm. Corresponding median survival times were 9.6, 9.3, and 7.3 months (P=0.61) respectively. The intent-to-treat response rate was 19, 22, and 13% respectively. Median progression-free survival was estimated with 4.0, 5.6, and 6.0 months (P=0.21). Grade 3/4 haematological toxicities were more frequent in the two GC-containing arms, no grade 3/4 febrile neutropaenia was observed. Conclusion: None of the three CRT regimens tested met the investigators' definition for efficacy; the median OS was similar to those previously reported with gemcitabine alone in LAPC.

In an open study, the efficacy of povidone-iodine in the prophylaxis of mucositis during antineoplastic radiochemotherapy was determined. 40 patients were randomly assigned to a treatment or control group (each 20 patients). All patients received standard prophylaxis of mucositis with nystatin, dexpanthenol, rutoside and immunoglobulin. In addition, the patients of the treatment group performed 4 times daily rinsing with povidone-iodine, the control patients with sterile water. Clinical examination of the oral mucosa was performed weekly during the radiation period and up to 6 weeks after the end of therapy. Oral mucositis was observed in 14 patients of the treatment group (mean grading: 1.0) and in all 20 patients of the control group (mean grading: 3.0). The mean onset of mucositis was after 2.25 weeks in treatment patients and 1.5 weeks in control patients. The mean total duration of mucositis was 2.75 weeks in treatment patients and 9.25 weeks in control patients. The mean AUC values were 2.5 in treatment patients and 15.75 in control patients. All findings were statistically significantly different between the two groups. It is concluded that rinsing with povidone-iodine reduces the incidence, severity and duration of oral mucositis during antineoplastic radiochemotherapy.

In palliative treatment, irregularly shaped fields are used to reduce side-effects and can improve, or avoid, field matching. We investigated the effectiveness of a multileaf collimator (MLC) supported by a digitizing data entry system in the palliative radiotherapy treatment of 66 patients and compared it with conventional shielding with geometrically shaped blocks. After conventional simulation of rectangular fields, irregular field shapes were marked on the simulator film in 17 patients (27%) to reduce radiotherapy related side-effects. Individual leading was performed with an MLC. Digitizing and fitting of the optimum leaf position were carried out using a multileaf preparation system (MLP, Elekta, Crawley, UK). Target volumes included bone metastases in the pelvis, spine and extremities, mediastinal soft tissues, lymph nodes and central nervous system. In 10 patients, treated with a parallel pair for pelvic metastases, MLC and conventional shielding were prospectively compared with regard to time requirements and area shielded. Compared with conventional blocking, the mean simulation, preparation and treatment time required for MLP fields was shorter (9.55 +/- 1.44 min vs 16.90 +/- 2.64 min, and 5.50 +/- 1.14 min vs 8.97 +/- 1.75 min). The mean shielded area was 31 cm2 larger for MLC fields compared with geometrically shaped blocks (p0.05). Compared with cerrobend blocking, the use of an MLC, supported by preparation data entry software, is more flexible and reduces radiotherapy resources. Therefore, a preparation data entry system as a separate device, or integrated into the treatment planning system, is a useful tool in palliative treatment.

The concept and performance of the fully depleted pn- junction CCD system, developed for the European XMM- and the German ABRIXAS-satellite missions for soft x-ray imaging and spectroscopy in the 0.1 keV to 15 keV photon range, is presented. The 58 mm X 60 mm large pn-CCD array uses pn- junctions for registers and for the backside instead of MOS registers. This concept naturally allows to fully deplete the detector volume to make it an efficient detector to photons with energies up to 15 keV. For high detection efficiency in the soft x-ray region down to 100 eV, an ultrathin pn-CCD backside deadlayer has been realized. Each pn-CCD-channel is equipped with an on-chip JFET amplifier which, in combination with the CAMEX-amplifier and multiplexing chip, facilitates parallel readout with a pixel read rate of 3 MHz and an electronic noise floor of ENC < e-. With the complete parallel readout, very fast pn-CCD readout modi can be implemented in the system which allow for high resolution photon spectroscopy of even the brightest x-ray sources in the sky.

The pn-charge coupled device (pn-CCD) detector system was developed as the focal plane instrument of an x-ray telescope for the European photon imaging camera (EPIC) on the x-ray multi mirror (XMM) mission. The second cornerstone mission of the European Space Agency's Horizon 2000 plan performs high throughput imaging and spectroscopy of the x- ray sky in the domain of 0.1 keV - 15 keV. The pn-charge coupled device will also be used for a German x-ray astronomy satellite mission, called ABRIXAS (a broad-band imaging x-ray all-sky survey). While XMM will perform pointed observations. ABRIXAS will carry out an all sky survey with imaging telescopes. Both projects are planned to be launched in 1999. The homogeneous coherent sensitive area of the detector consists of a 6 cm by 6 cm large array of 12 pn-CCDs which are monolithically integrated on a single silicon wafer together with the first stage of amplification. The pn-CCD detector has been optimized for high-resolution x-ray spectroscopy and its performance is close to the theoretical limits given by the Fano noise. High quantum efficiency essential for the investigation of faint objects is accomplished over the whole energy range by a thin photon entrance window and a full sensitive detector thickness. A fast readout achieves excellent time resolution for the observation of pulsed x-ray sources and avoids pile- up for bright objects. The relevant performance parameters reflecting the state of the detector development are presented. The radiation hardness of the pn-CCD was verified for the ten year satellite mission. No significant increases in the thermally generated current, charge transfer losses and transfer noise occurred in the temperature range planned for detector operation. A correction of the signal charge losses, which occur already before irradiation in all types of charge coupled devices during the charge transfer to the anodes, is necessary to achieve the highest energy resolution of the detector. Methods to reduce the signal charge losses which were successfully tested, are described.