A technique for analysing breast lesions could reduce the number of biopsies performed on what are later found to be benign tumours, scientists claim.
A review of almost 2,600 breast MRI exams carried out during a four-year period at the Seattle Cancer Care Alliance in the US found three factors which, when used together, could predict the likelihood of malignancy.
MRI exams are so sensitive they reveal cancerous and non-cancerous lesions that often look alike and behave similarly when contrast dye is injected into a patient.
Biopsy is often necessary to determine whether a lesion is cancerous.
Wendy DeMartini and colleagues in the breast imaging department found three characteristics that, when taken together, were the best at predicting malignancy.
The most likely lesions to be malignant are: those found in women undergoing MRI in order to look for additional malignancy after new breast cancer diagnosis; those found to be larger than one centimetre; and those where the enhancement quickly fades (called washout).
The study found that breast lesions in women screened because they were considered to be at high risk, those that were found to be small lesions, and legions that increased their enhancement over time were very likely to be benign.
DeMartini warned that more research is needed before this statistical model can be validated for use as standard practice.