Additional occult cancers identified on staging breast MRI: imaging appearances and pathologic characteristics

Area of Science:

• Oncology
• Radiology
• Medical Imaging

Background:

• Breast magnetic resonance imaging (MRI) demonstrates high sensitivity for detecting additional cancers (ACs) in breast cancer patients.
• The clinical implications of diagnosing and treating these MRI-identified ACs are not yet fully understood.

Purpose of the Study:

• To compare the characteristics of index cancers (ICs) with additional cancers (ACs) detected by breast MRI.
• To evaluate the potential clinical significance of ACs identified through breast MRI staging.

Main Methods:

• Retrospective analysis of 18 breast cancer patients with 19 ICs and 19 ACs diagnosed via MRI between 2012-2020.
• Review of pathology reports and breast MRI examinations.
• Statistical comparison of ICs and ACs using chi-square, Fisher's exact, and Wilcoxon signed rank tests.

Main Results:

• Additional cancers (ACs) were more frequently in situ (ductal carcinoma in situ) compared to index cancers (ICs) (P=0.021).
• ACs more often presented as nuclear grade 2 (P=0.009).
• While not statistically significant, some ACs exhibited characteristics (type, size >10mm, or nuclear grade) suggesting potential clinical relevance.

Conclusions:

• Breast MRI-detected ACs are often in situ and nuclear grade 2.
• Some ACs possess features indicating potential clinical significance.
• Further research is needed to determine the definitive impact of ACs on clinical management.