Interpretation: ACR Preliminary MRI Breast Lexicon Classification Form
LESION TYPE (select one)
A. Focus/Foci (Tiny spot of enhancement) GO TO SECTION D
B. Mass (3-dimensional space occupying lesion that is one process, usually round, oval, or irregular in shape).
| Shape (select one) | Description |
| Round | Spherical or ball-shaped |
| Oval | Elliptical egg-shaped |
| Lobulated | Undulating contour |
| Irregular | Uneven shape (not round, oval or lobulated) |
| Margin (select one) | Description |
| Smooth | Well-circumscribed and well-defined margin |
| Irregular | Uneven margin can be round or jagged (not smooth or spiculated) |
| Spiculated | Characterized by radiating lines |
| Mass Enhancement (select one) | Description |
| Homogeneous | Confluent uniform enhancement |
| Heterogeneous | Non-specific mixed enhancement |
| Rim enhancement | Enhancement more pronounced the periphery of mass |
| Dark internal septation | Dark non-enhancing lines within a mass |
| Enhancing internal septation | Enhancing lines within a mass |
| Central enhancement | Enhancement more pronounced at center of mass |
C. Non-Mass Enhancement (that is in an area that is not a mass)
| Non Mass Enhancement (select one) | Description |
| Focal | Enhancement in a confined area |
| Linear | Enhancement in a line that may not conform to a duct |
| Ductal | Enhancement in a line that may have branching, conforming to a duct |
| Segmental | Triangular region of enhancement, apex pointing to nipple, suggesting a duct or its branches |
| Regional | Enhancement in a large volume of tissue not conforming to a ductal distribution, geographic |
| Diffuse | Enhancement distributed uniformly throughout the breast |
| Non-Mass Enhancement (internal enhancement) (select one) | Description |
| Homogeneous | Confluent uniform enhancement |
| Heterogeneous | Non-uniform enhancement in a random pattern |
| Stippled, punctate | Punctuate, similar appearing enhancing foci, sand-like or dot-like |
| Clumped | Cobblestone-like enhancement, with occasional confluent areas |
| Reticular, dendritic | Enhancement w/finger-like projections extending toward nipple, especially seen on axial or sagittal images |
Describe if findings are asymmetric, more in one breast than in the other
D. Other Findings (select all that apply)
| None apply | Edema |
| Nipple retraction | Lymphadenopathy |
| Nipple invasion | Pectoralis muscle invasion |
| Pre-contrast high duct signal | Chest wall invasion |
| Skin thickening (focal) | Hematoma/blood |
| Skin thickening (diffuse) | Abnormal signal void |
| Skin invasion | Cysts |
E. Assessment (select one)
| Impressions | Recommendations | |
| 0 | Incomplete | Additional evaluation needed before final assessment |
| 1 | No abnormal enhancement | No lesion found (routine follow-up) |
| 2 | Benign | Benign, no malignant features; example cyst (routine follow-up) |
| 3 | Probably benign | Probably benign (short interval follow-up) |
| 4 | Suspicious abnormality | Suspicious for cancer (biopsy) |
| 5 | Highly suggestive of malignancy | High probability of cancer (biopsy) |