[en] Cancer services, such as screening, surgery, chemotherapy or radiotherapy, should be delivered in the type and amount that meet local demand. Estimating demand requires knowledge of the types and numbers of cancers and the indications for services. For example, the demand for breast screening can be calculated by determining the number of women aged 50 to 70 years old. It is more complicated to determine the demand for services, such as radiotherapy or chemotherapy, that have a large number of indications relevant to small proportions of the cancer population. Different populations will have different incidence rates of cancer, and the proportions of the common types of cancer may vary. Cancer registries provide information on the types and frequency of cancer in a population. They may also record data about stage at presentation, which has a critical influence on the outcomes. In addition, factors relating to specific groups of patients, such as performance status and co-morbidities, may alter treatment recommendations. Unfortunately all these details are often poorly recorded by cancer registries. Nevertheless, planning of sufficient services to meet the needs of the treatment population is vital in providing optimal care. This chapter describes an evidence based approach to estimating the demand for radiotherapy, and its application to different treatment modalities and different populations. The work was done mainly for Australia, but has been used in Europe and North America. Cancer services include all cancer control interventions, such as screening, early detection, diagnosis, treatment, palliation and rehabilitation. The estimation of the demand for radiotherapy will be described in detail, and examples given of how this approach has been adapted to other modalities and other populations.

[en] Short communication

[en] It has previously been suggested that approximately 50% of all cancer patients should receive radiation. However, this estimate is not evidence-based. To estimate the ideal proportion of new cases of cancer that should receive external beam radiotherapy at least once during the course of their illness based on the best available evidence, and develop a model of radiotherapy utilisation that is useful for future changes in cancer incidence, stage at presentation and indications for radiotherapy. A systematic review of international guidelines on the treatment of cancers of the specific tumour-sites was undertaken. An optimal radiotherapy utilisation tree was constructed, depicting the indications for radiotherapy at various stages of cancer. The proportion of patients with clinical attributes that indicated a benefit from radiotherapy was obtained by inserting epidemiological data into the radiotherapy utilisation tree. The optimal proportion of patients with cancer that should receive radiotherapy was then calculated using TreeAge software The proportion of cancer patients in whom external beam radiotherapy is indicated was calculated to be 53% of all cancer. This estimate includes the following recommended optimal radiotherapy utilisation rates for the commonest cancers - breast 83%, lung 76%, prostate 60%, rectum 61%, melanoma 23% and gynaecological cancer 31%. Ideal utilisation rates for each cancer were compared with the published utilisation rates of radiotherapy in Australia and internationally over the last decade. Significant differences were found between the evidence-based recommended radiotherapy utilisation rate and the actual rates reported in clinical practice particularly for rectal and prostate cancer. This methodology allows comparison of optimal rates with actual rates to identify areas where improvements in the evidence-based use of radiotherapy can be made and provides valuable data for radiotherapy service planning

[en] ⁸⁷Sr/⁸⁶Sr, major and trace element data are presented for calc-alkaline lavas from Santorini and Milos, Aegean Sea, Greece, ⁸⁷Sr/⁸⁶Sr ratios of fresh lavas from Santorini range from 0.70472 to 0.70509 whereas those of fresh lavas from Milos lie in the range 0.70540-0.70620. Altered lavas from both islands have higher ⁸⁷Sr/⁸⁶Sr ratios (up to 0.70573 and 0.70662 respectively). The range of ⁸⁷Sr/⁸⁶Sr ratios of fresh lavas from Santorini is only just greater that the maximum analytical uncertainty and is thus considered to reflect that of the parental magmas from which the lava series was derived (by fractional crystallization at low pressures). For the analysed Milos lavas (dacite-rhyolite) there is no correlation between ⁸⁷Sr/⁸⁶Sr and any major or trace element concentration and this, together with the fact that the ⁸⁷Sr/⁸⁶Sr ratios are similar to those of basaltic andesites and andesites from Aegina and Methana in the northwestern part of the arc, likewise indicates that the ⁸⁷Sr/⁸⁶Sr ratios are identical to those of the parental magmas from which the lava series was derived (also by fractional crystallization). The relatively high ⁸⁷Sr/⁸⁶Sr ratios of the Santorini and Milos parental magmas indicate that terrigeneous material has played a role in their genesis. This could be either via the subduction process or by assimilation of lower crustal material during ascent of mantle-derived magmas. The weight of the available evidence favours the latter possibility, but, even so, there are some indications that unusual mantle source material was involved in the genesis of the magmas. (orig.)

[en] A partial study for a 6 GeV undulator based synchrotron radiation source for production of high brightness undulator radiation, in the A region, is presented. The basic lattice adopted for the storage ring is a hybrid FODO Chasman-Green lattice, making use of gradient in the dipoles. We discuss also the e beam current limits and the injection parameters

[en] Methods of analysis of microwave propagation through superconducting thin films with buffer layers on dielectric substrates have been discussed. Expressions describing the transmission coefficient S₂₁ through the structure and the complex conductivity sigma of a superconductor in an analytical form have been derived. The derived equations are valid for microwave propagation in waveguides as well as in free space with relevant definition of impedances. Using the obtained solutions, the influences of buffer layers' parameters (thickness, relative permittivity and loss tangent) on the transmission coefficient has been investigated using MATLAB. Simulations have been performed for 10 GHz transmission through YBa₂Cu₃O₇ films on sapphire with SrTiO₃ and CeO₂ buffer layers and on silicon with CaF₂ and YSZ buffer layers. To illustrate the simulations, measurements of the transmission through YBCO film on sapphire with SrTiO₃ buffer layer have been performed. It has been shown that even lossy buffer layers have very little impact (smaller than 1% in magnitude and 0.3% in phase) on the transmission coefficient through superconducting thin films, providing their thickness is below 10 mu m. (author)

No abstract available

[en] A partial study for a 6 GeV undulator based synchrontron radiation source for production of high brightness undulator radiation, in the A region, is presented. The basic lattice adopted for the storage ring is a hybrid FODO Chasman-Green lattice, making use of gradient in the dipoles. The authors discuss also the e beam current limits and the injection parameters

[en] The purpose of the present study was to examine utilization rates of radiotherapy by newly diagnosed cancer patients in New South Wales (NSW) from 1996 to 1998. The 1989 report of the Australian Health Ministers' Advisory Council (AHMAC) recommended that 50% of all newly diagnosed cancer patients should receive radiotherapy. Previous reports showed that the true rate was between 30 and 36%. In 1991 and 1995 the NSW Department of Health developed strategic plans that were intended to implement the AHMAC recommendation. An analysis was carried out of activity reports of radiation oncology departments in NSW and its component Area Health Services (AHS). All NSW patients newly diagnosed with cancer between 1996 and 1998 and treated by radiotherapy were included in the study. A total of 37% of newly diagnosed cancer patients received radiotherapy in NSW in 1998. This has increased from 30% since 1990-91. Rural AHS in 1998 had an identical average rate of 37% (range: 23-54%) when compared to urban AHS (average: 37%; range: 26-49%). Rural AHS have increased utilization from 19% in 1990-91. Area health services with a radiation oncology department had a slightly higher rate of utilization than those AHS without a radiation oncology department (39 and 36%, respectively). The rates of utilization of radiotherapy in NSW in 1998 continued to be well below the benchmark set by AHMAC and varied widely between AHS. Attention to and expansion of services should be focused on both rural and urban areas of need. Copyright (1999) Blackwell Science Pty Ltd

[en] Full text: ⁹⁹Tc^m(V)-DMSA [DMSA(V)] has shown promise in brain tumour imaging. This study aimed to assess the role of DMSA(V) brain SPET in glioma for: (1) predicting the histopathological grade of malignancy, (2) monitoring response to therapy and (3) discriminating recurrent tumour from post-radiotherapy necrosis. Twenty-three patients (pts) (14 men, 9 women) of mean age 57 years (range 20-79) were referred with a lesion on CT/MRI (14 new presentations, 5 known and 4 suspected tumour recurrence). Up to 555 MBq of ⁹⁹Tc^m(V)DMSA were administered and SPET was acquired at 3 h. Tumour uptake ratio (UR) was calculated by the ratio of activity in the tumour to a region in the contralateral brain. All 19 pts with known tumour showed DMSA(V) uptake. The 14 pts with new tumours (10 grade IV, I grade III, 2 grade II and 1 necrotic tumour) had a pre-therapy mean UR of 7.7 (range 2.8-13.6). The 3 lower-grade tumours were scattered widely within this range. Four pts completed radiotherapy and returned for a post-therapy scan, where the UR was less than the pre-therapy UR in 2, unchanged in 1 and greater in 1. The 5 known recurrent tumours had a mean UR of 13.5 (range 7.3-24.9). In the 4 pts with suspected recurrence, the DMSA(V) scan result agreed with clinical course or PET in 3 but was falsely positive in 1. In summary,⁹⁹Tc^m(V)-DMSA: (1) showed uptake in all known glial cell tumours in this series, however the UR did not correlate with the histopathological grade; (2) may be useful for discriminating tumour recurrence from post-radiotherapy necrosis; and (3) may have a role in predicting post-therapy prognosis