A systematic overview of radiation therapy effects in urinary bladder cancer

A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for urinary bladder cancer is based on data from 3 meta-analyses and 33 randomized trials. The studies include 4333 patients. The results were compared with those of a similar overview from 1996 including 15,042 patients. The conclusions reached can be summarized as these points: There is moderate evidence for an overall survival benefit with preoperative radiotherapy followed by cystectomy compared to curative radiotherapy based on early studies (1964-1986). Since that time surgical as well as radiation techniques have developed considerably. Therefore, the conclusion may not be relevant to modern treatment of invasive urinary bladder carcinoma. There is only one small study reporting on curative radiotherapy where increased dose per fraction is compared with conventionally fractionated radiotherapy to the same total dose. Thus, no conclusions can be drawn concerning optimal fraction dose. A meta-analysis based on two studies on hyperfractionated radiotherapy gives moderate evidence of a survival benefit at 5 and 10 years and an increased local control rate compared with conventional fractionation. The documentation of local control and overall survival rate after split-course radiation treatment compared to continuous therapy is conflicting. No firm conclusions can be drawn. Four small and early studies have compared radiation treatment using neutrons with photon treatment. The reports favour therapy with photons with respect to overall treatment results. There is moderate evidence for this conclusion. There is fairly strong evidence in early studies that radiation treatment in combination with hyperbaric oxygen does not confer a treatment benefit compared to radiation in normal atmosphere. There is no indication of a treatment benefit with the addition of either hyperthermia or misonidazole. A large number of phase II studies, suggesting an increased possibility for bladder preservation with concomitant chemoradiotherapy compared to radiotherapy alone, have been reviewed in a previous SBU report on chemotherapy. Only one small randomized study has been reported where concomitant chemoradiotherapy with cisplatin is compared to radiation alone. No conclusion on the therapeutic benefit of combined treatment can be drawn. Large randomized studies are needed. There is some evidence that preoperative radiotherapy followed by cystectomy does not confer any significant survival benefit compared to cystectomy alone. There is moderate evidence that palliative radiotherapy of invasive bladder carcinoma can rapidly induce tumour-related symptom relief. There is moderate evidence that palliative hypofractionated radiotherapy, 3 fractions during one week, gives the same relief of symptoms as 10 fractions during 2 weeks.