More breast cancer patients with large palpable tumors are now undergoing chemotherapy before surgery in an effort to reduce the size of their tumor, and MRI is the best way to predict if the chemotherapy is working, preliminary results of a study show. If the chemotherapy is successful, then the woman may be able to undergo breast-conservation surgery rather than a mastectomy.
Currently, it is standard practice for the physician to do a breast examination to non-invasively assess whether the chemotherapy was effective, said Eren Yeh, MD, an instructor of radiology at Massachusetts General Hospital in Boston, and the lead author of the study. “Before we began the study, we weren’t sure if breast tumors would enhance with the MR contrast agent gadolinium and therefore be visible after chemotherapy. Our study found that MRI is not perfect, but it’s better than what’s been used as the gold standard in the past,” she said.
For the study, 31 patients prospectively underwent clinical examination, mammography, sonography and an MRI examination before, then following, chemotherapy. The results of these tests were then compared to the pathology results following surgery. MRI was right (when compared to pathology results) 71% of the time. It overestimated the amount of residual tumor in 6% and underestimated the amount of residual tumor in 23% of patients.