Fifty-eight patients presenting with axillary symptoms (pain, oedema, etc) following radiation therapy for breast carcinoma were randomized to be investigated by either computed tomography (CT: 29 patients) or magnetic resonance imaging (MRI: 28). The objectives of the study were to compare the efficacy of the two tests in identifying the presence of tumour and their effectiveness as judged by quality of life (QOL) outcome measurements. Both tests proved efficacious; the predictive values for a positive result (tumour present) were 100% for both tests; the predictive values for negative findings were in the range of 76 to 90% for CT and 81 to 100% for MRI. As regards outcome, complete QOL data were available in 37 patients (17 of these patients had CT, 20 MRI). Although the mean change in QOL over 6 months was slightly more favourable in the patients investigated by MRI than in the CT group, the difference did not reach statistical significance.