Detection of Contralateral Malignancies on Breast MRI

Area of Science:

• Oncology
• Radiology
• Medical Imaging

Background:

• Women diagnosed with unilateral breast cancer face an elevated risk of developing simultaneous contralateral breast cancer.
• Early detection of contralateral breast cancer is crucial for preventing additional treatments and improving overall survival rates.
• Despite its benefits, MRI screening for contralateral breast cancer is underutilized after an initial unilateral diagnosis.

Purpose of the Study:

• To retrospectively evaluate the efficacy of breast MRI in detecting contralateral breast cancer in patients already diagnosed with unilateral breast cancer.
• To compare the detection rates of contralateral breast cancer between mammography (MAM) and MRI.
• To assess the impact of MRI-detected contralateral cancers on patient management and treatment.

Main Methods:

• Retrospective chart review of women diagnosed with synchronous bilateral breast cancer between January 2017 and January 2022.
• Analysis of mammography (MAM) and MRI imaging reports to identify contralateral breast cancer.
• Review of surgical pathology reports for histological type and TNM staging of contralateral cancers.

Main Results:

• Mammography (MAM) missed contralateral cancer in 17 cases, of which MRI detected malignancy in 12 cases (70.59%), leading to changes in management.
• The detection rate of contralateral breast cancer by MAM alone was 45.45% (15/33).
• Cancers missed by MAM were predominantly early-stage (T1 or Tis) with no nodal involvement, indicating MRI's potential for detecting occult malignancies.

Conclusions:

• Breast MRI demonstrates superior ability in detecting contralateral breast cancer compared to mammography (MAM).
• MRI significantly increases the detection rate of synchronous contralateral breast cancer, often identifying early-stage disease.
• The utility of MRI in staging and detecting occult contralateral malignancies justifies its cost and should be considered in future clinical practice.