Several phase III studies (Quilty et al, 1982;Lewington et al, 1991;McEwan et al, 1994;Malmberg et al, 1997) now support the usefulness and cost effectiveness of Sr-89 either as an alternative or an adjunct to external beam radiotherapy (EBRT) in men with bone pain due to metastatic prostate cancer. Primary study end points have included pain response presented in terms of reduction in severity and/or frequency of pain and/or analgesic use, delayed onset of new painful sites and/or decrease in EBRT requirement over the patient's remaining lifetime.It is recognized that the effects of palliative treatment extend beyond simply reducing the severity of a reference symptom, such as pain. Health-related QoL describes a multidimensional view of a patient's psychological and social, as well as physical wellbeing. Despite the frequent citing of the importance of overall QoL in men with metastatic prostate cancer and the potential impact that Sr-89 might have on QoL, there has been little attention paid to formal evaluation of QoL as a primary end-point in the study of Sr-89 to date.The Trans Canada Study Group (Porter et al, 1993) undertook a limited QoL evaluation and found that in the areas of physical mobility and pain control, Sr-89 produced a significant beneficial effect for men with metastatic prostate cancer. This assessment, as the authors acknowledge, was not ideal in that a standardized instrument was not used and conclusions were based on data pooled from a number of non-validated instruments including linear analogue self assessment scales, questionnaires and patient diaries.Following the establishment of a Government reimbursement in early 1995, Sr-89 therapy for the relief of bone pain due to prostate cancer became widely available in Australia. A group of interested Radiation Oncologists (the Australian Metastron User's Group) took this opportunity to initiate a prospective study to (1) confirm that treatment efficacy and toxicity were consistent with the world literature and to (2) simultaneously assess the nature and time course of any possible QoL benefits using a validated instrument. Secondary end-points included toxicity, (specifically bone marrow depression, pain 'flare' and/or other unexpected morbidity), and PSA 'response' following Sr-89.
MATERIALS AND METHODSThis was a prospective multicentre study involving 13 oncology centres in 5 states and territories of Australia. Accrual took place over a two-year period from mid 1995 to mid 1997. There was a minimum 8-month interval from the date of Sr-89 injection in the last study patient to analysis, with a median follow up overall of 6.8 months (censoring patients at death).Eligible patients were those who had histologically proven prostate cancer with bone scan evidence of metastatic disease and who had progressed either clinically, biochemically or both following 'standard' first-line hormone therapy (with or without further hormonal manoeuvres), and who had one or more sites of bony pain. 7 patients had previously been treated with various chemot...
