The use of MR imaging to predict invasive breast cancer prognosis

This study investigated the use of magnetic resonance (MR) imaging as a prognostic tool in primary breast cancer (BC) patients. The study concluded that MR imaging can identify features which can be used to help predict the risk of distant metastasis (cancer spread to other areas) in patients.

Between 20-30% of BC patients develop a distant metastasis. Some factors, such as younger age, large tumor size and human epidermal growth factor receptor 2 (HER2) over expression, among others, are known predictors of disease spread. However, predicting risk on an individual basis remains difficult.

Patients often undergo an MRI (a type of scan that uses magnetic fields to image the organs and tissues of the body) at the time of diagnosis. It is not clear whether any features seen in the MR image can predict future metastasis.

This study examined the medical records of 294 women who were diagnosed with invasive BC. All underwent breast MR imaging prior to surgery. 147 women who developed a distant metastasis were compared to 147 who did not. The follow up time ranged from 0.9 to 11.4 years.

Rim enhancement (signs of more growth at the edges of the tumor) and peritumoral edema (swelling around the tumor) were MR image features observed most frequently in metastasis patients. These features were also associated with worse DM-free survival in invasive BC patients.

Different subtypes and stages of BC were found to be associated with different features. Rim enhancement was associated with an 87% increased risk of metastasis in patients with hormone receptor positive and HER2 negative breast cancer, and a 2.1-fold increased risk in patients with HER2 positive breast cancer. Peritumoral edema was associated with a 2.61-fold increased risk in hormone receptor positive, HER2 negative breast cancer.

This study concluded that MR imaging can identify features which can be used to help predict the risk of DM in patients. Rim enhancement and peritumoral edema in particular were associated with worse DM-free survival in BC patients overall.

The study relied on patient records from a single academic institution and as such, may not have been properly randomized. The patients were also not matched for surgery or treatment type, which may have affected the patient outcomes observed. Additionally, the small number of patients included in the study means the results may not be applicable to the general population.

Discuss the use of MR imaging with your physician as part of individualizing your treatment.