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The European Organization for Research and Treatment of Cancer (EORTC) Radiotherapy Group initiated its mailed thermoluminescence dosimetry (TLD) programme in 1986. The aim of the present study was to evaluate the clinical relevance of variations in beam output detected in the period 1993 to 1996. A total of 140 beam outputs were checked (26 for cobalt-60 units and 114 for linear accelerators) in 35 centres. Clinical dose-response data for tumour control and normal tissue morbidity were used to assess the variation in clinical outcome resulting from variability in beam output. For 75 checked beams with nominal accelerating potentials (n. a.p.) of 6 MV or less the mean ratio, +/- standard deviation (S.D.) of measured to stated output was 1.004+/-0.020. For 65 beams with n. a.p. of 8 MV or more, the ratio was 1.009+/-0.021. Even with this relatively high level of precision, broad distributions of estimated tumour control or normal tissue morbidity were found. In the 10% of the beams with the most pronounced underdosage, the loss in tumour control probability was estimated at 7-8 percentage points. Likewise, in the 10% of the beams with the most pronounced overdosage, the increase in mild/moderate morbidity was 19-22 percentage points. For severe morbidity the same beams raised the estimated incidence of severe complications from 5% to 9-10%. An estimation of the loss of uncomplicated cure probability was about 1% for both high and low energy beams. Sequential mailings considerably improved the uniformity of clinical outcome. We conclude that small deviations in beam output may lead to clinically important variations in outcome. Substantial reductions in the variation between measured and stated output can be achieved by sequential mailings. Mailed TLD checks should be an integral part of a continuously ongoing quality assurance activity in radiotherapy.

Wedge factor ( WF ) variation with field size and depth has been analysed for 6 and 15 MV X-ray beams. The measured field size effect is 1.4% in the worst case, whereas the WF shows a linear dependence with depth giving a maximum variation of 0.22%/cm (60 ° wedge, 6 MV beam). An empirical correction for WF depth dependence on wedge thickness is proposed.

The results of a dummy run involving nine centers participating in a study comparing radiotherapy alone with radiotherapy plus hormone therapy in patients with high metastatic risk prostatic cancer (EORTC protocol 22863) show that, in all centers but one, patients are treated in the same way. However, they have also indicated that protocol compliance could be improved by a better assessment of the target volume, by taking into account of the use of protective shields and of variations in radiological density, by determining beam position on a large number of slices, and by the use of CT scan images for treatment planning.

Autologous chondrocyte implantation (ACI) is a frequently used procedure for full-thickness cartilage lesions in the knee joint. However, to date, there are just a few prospective, randomized clinical studies and most publications are case series on small and heterogenic cohorts with short-term follow-up. To date, ACI is a surgical treatment option for single traumatic lesions on the distal femur in young active subjects with a recent lesion. Lesion size should be between 3 and 8 cm2,6 mm in depth, tidemark preserved without penetration of the subchondral bone. Absolute contraindications for ACI include osteoarthrosis, kissing lesions, lesions size greater than 10 cm2 or deeper than 8 mm, ligament instability, partial or total meniscectomy, axis malalignment5. Further studies are mandatory to determine the precise indications to the technique and to show its superiority on the established treatment of chondral lesions.

Evaluation of diagnostic accuracy of high-spatial-resolution sonography (HSR-S) in occult scaphoid fractures.HSR-S was performed in 24 patients with clinically suspected fracture and normal radiographs. Three levels of clinical suspicion were considered (high, intermediate, and low). Three levels of sonographic suspicion were defined on the basis of cortical interruption, radiocarpal effusion, and scapho-trapezium-trapezoid effusion. Three positive criteria were interpreted as being highly indicative of fracture. Data from sonograms were compared with computed tomography (CT) scans.CT scanning demonstrated a fracture of the scaphoid in five patients. The global sensitivity of HSR-S for detection of occult scaphoid fracture was 100% and the specificity 79%. All patients with demonstrated occult fracture had a high sonography index of suspicion. A high sonography index of suspicion was correlated with 100% sensitivity, specificity, positive predictive value, and negative predictive value.HSR-S is a reliable, available, and cost-effective method in early diagnosis of occult fractures of the scaphoid. The presence of three defined criteria is required to assess the diagnosis.

In 1982, the European Organization for Research and Treatment of Cancer (EORTC) Radiotherapy Group established the Quality Assurance (QA) programme. During the past 20 years, QA procedures have become a major part of the activities of the group. The methodology and steps of the QA programme over the past 20 years are briefly described. Problems and conclusions arising from the results of the long-lasting QA programme in the EORTC radiotherapy group are discussed and emphasised. The EORTC radiotherapy group continues to lead QA in the European radiotherapy community. Future challenges and perspectives are proposed.

The safe application of ionising radiation for diagnosis and therapy requires a high level of knowledge of the underlying processes and of quality assurance. Sophisticated modern equipment can be used effectively for complicated diagnostic and therapeutic techniques only with adequate physics support. In the light of recent analyses and recommendations by national and international societies a joint working group of representatives from ESTRO (European Society for Therapeutic Radiology and Oncology) and from EFOMP (European Federation of Organisations for Medical Physics) was set up to assess the necessary staffing levels for physics support to radiotherapy. The method used to assess the staffing levels, the resulting recommendations and examples of their practical application are described.

In recent years, numerous publications have shown the feasibility and usefulness of in vivo dosimetry as an essential tool of quality assurance programs in radiotherapy [ 1,3,6,11]. In the context of this meeting on high dose/high precision radiotherapy, the presentations and discussions on in vivo dosimetry centred on its value for investigating the quality of specific treatment techniques: accuracy and reproducibility in dose delivery, benchmark role of in vivo dosimetyy, frequency of in vivo measurements and action levels for corrective actions.

A consensus on a quality assurance programme of the treatment of early breast cancer was reached in a multidisciplinary meeting of surgeons, pathologists, radiotherapists, physicists and radiographers. Guidelines for treatment preparation and execution have been set up, including careful location and excision with marking of the primary tumour. The target volumes for irradiation of the whole breast and boost area have been defined. Radiation dose prescription rules, specification and checking procedures are given, together with measures to achieve a homogeneous dose within the target volume. The rules for a quality assurance programme in each clinic are designed for checking equipment and treatment method.

ADPKD is the most widespread genetic nephropathy. Only twenty-five per cent of patients are symptomatic. In order to prevent the disease it is important early screening by ultrasonography that shows a typical picture only in adults. Familiar history is determinant for diagnosis in intrauterine age, in newborns and in infants. Ultrasonographic diagnosis is certain only after twenty-five weeks of pregnancy.

In 111 patients with essential hypertension (World Health Organization stage I or II), we examined the relationship between renal hemodynamics and left ventricular hypertrophy. Left ventricular structure was determined by two-dimensional guided M-mode echocardiography, renal blood flow by iodine I 131 aminohippuric acid clearance, and glomerular filtration rate by creatinine clearance. The glomerular filtration rate correlated with left ventricular mass (r = .52) and left ventricular cross-sectional area (r = .21). Conversely, at a similar age, body mass index, body surface area, and arterial pressure, hypertensive patients with left ventricular hypertrophy disclosed a higher glomerular filtration rate and filtration fraction than those without left ventricular hypertrophy, whereas renal blood flow and renal vascular resistance measurements were not significantly different. Thus, at similar levels of arterial pressure and renal blood flow, glomerular hyperfiltration was linked to early cardiac structural changes in essential hypertension. We conclude that, in a hypertensive patient with normal renal function, a high glomerular filtration rate may be an indicator for early target organ damage in essential hypertension.

The central nervous system of young children is particularly sensitive to neurological damage due to excessive lead exposure. The lead stored in a tooth is permanent and related to the quantity of ingested lead. The lead is assayed by measuring the characterisitc radiation from lead in a tooth in situ irradiated with gamma rays from a cobalt-57 source. The sensitivity of the method is adequate to measure lead levels commonly associated with environmental background. The X-ray exposure to the tooth necessary for this determination is approximately one tenth of that required for a routine dental examination.

Hyperlipoproteinemia was found in 200 patients affected by chronic renal failure on maintenance hemodialysis, due to increase in Total Cholesterol, VLDL-TG, LDL, TG, LDL and VLDL. In 30 of these patients, the analysis was extended to the dosing of decreased Total Serum HDL-Cholesterol, HDL2, HDL3, Apoprotein A and Apoprotein A1 values, and of increased Apoprotein B values. These findings further contribute to proving accelerated atherogenesis in the patients examined.

Cardiac performance, as judged by preload, afterload, and myocardial contractility, was evaluated by non-invasive M-mode echocardiography before and after acute oral administration of calcium entry blockers (nitrendipine and verapamil), angiotensin converting enzyme (ACE) inhibitors (captopril and lisinopril), and a dopamine receptor agonist (fenoldopam) in patients with mild to moderate essential hypertension. Left ventricular end diastolic volume was taken as an index of preload, end systolic stress as an index of afterload, and the ratio of systolic pressure to end systolic volume (SBP:ESV), ejection fraction (EF), and mean velocity of circumferential fibre shortening (Vcf) as indices of contractility. Reductions of afterload and mean arterial pressure were achieved with all antihypertensive agents involved (mean percentage change +/- s.e.m.: 15 +/- 2% and 10 +/- 1%, respectively, P0.05) but the afterload reduction with lisinopril was greatest (21 +/- 9%; P0.01). The dopamine receptor agonist fenoldopam decreased by preload 24% (P0.05) and increased all of the three parameters of myocardial contractility (SBP:SV 66%; EF 17%, Vcf 19%; P0.01). In contrast, no effect on these parameters was observed with either calcium entry blocker or either ACE inhibitor.