NME Distribution — Diffuse
Diffuse NME describes enhancement distributed throughout a large portion of the breast, typically involving 2 or more quadrants.
Definition
Enhancement distributed throughout a large portion of the breast, typically 2 or more quadrants. The enhancement is widespread and not confined to a segment, duct, or focal region.
Imaging Appearance
- Early post-contrast T1W: extensive enhancement throughout the majority of the breast on axial and/or sagittal images
- Involves bilateral or extensive unilateral breast parenchyma
- Does not follow a ductal, segmental, or regional distribution
Differential Diagnosis
| Diagnosis | Supporting Features |
|---|---|
| IDC | Diffuse heterogeneous NME; large, invasive cancer |
| ILC | Diffuse heterogeneous; ILC is classically diffusely infiltrating |
| DCIS with microinvasion | Diffuse heterogeneous or clustered ring NME |
| Marked BPE | Symmetric bilateral; physiologic; no unique finding |
| Inflammatory breast cancer | Diffuse enhancement + skin thickening + erythema |
Board Pearl
Diffuse NME can be malignant (IDC, ILC, inflammatory carcinoma). Always compare to the contralateral breast and assess for bilaterality (favors BPE) versus unilateral predominance (favors pathology).
Pitfall
Marked BPE can mimic diffuse NME. Key distinction:
- BPE: bilateral, symmetric, follows known BPE patterns (peripheral, scattered dots)
- Diffuse NME: unique enhancing finding distinct from BPE pattern, often unilateral or asymmetric
Examples from Source
- Diffuse, heterogeneous NME → DCIS with microinvasion
- Diffuse, clustered ring NME → IDC and DCIS
- Diffuse, heterogeneous NME → ILC