The clinical utility of magnetic resonance imaging (MRI) in judging therape
utic response of bone metastases was evaluated in 18 patients with advanced
breast cancer Treatment efficacy was assessed by MRI and conventional meth
ods such as plain radiograph, bone scan, pain and analgesic scale, and seru
m CA15-3. The response by MRI was evaluated mainly on TI-weighted sequences
by measuring the volume of the bone lesion and soft tissue component. The
patient was assumed to be a conventional responder if a complete or partial
response was observed in any of the conventional methods described above.
Response was most concordant between plain radiographs and MRI findings (91
%, 10/11, 95% confidence interval [CI]: 58.7-99.8). The rate of concordance
was 61% (11/18, 95% CI 35.8-82.7) for all conventional methods and MRI. MR
I revealed response in four patients in whom progressive disease was observ
ed by bone scan and the marker response was not measurable. This pilot stud
y suggests that posttherapy evaluation with MRI may provide useful clinical
information in breast cancer patients with bone metastases and may be a va
luable adjunct to conventional methods with conflicting results.