Month: June 2025

D. Asymmetry

Explanation: There is an asymmetry in the medial right breast which is seen only on the CC projection, with no MLO view correlate. According to the ACR BI-RADS Atlas, an asymmetry is a unilateral deposit of fibroglandular tissue that does not meet the definition of a mass and is seen on only one mammographic projection (this is in contrast to a focal asymmetry, which is seen on two projections).

There are findings related to prior lumpectomy and radiation in the posterior right breast. With the exception of a slight increase in several benign-appearing dystrophic calcifications, these post-treatment findings are stable compared to last year’s mammogram and not worrisome.

A. BI-RADS 0 (Incomplete); Recommend diagnostic mammogram and ultrasound

Explanation: The appropriate next step is a diagnostic work-up, starting with a diagnostic mammogram, and following with an ultrasound if the asymmetry persists on the spot diagnostic images. Although a new asymmetry is worrisome, there is a possibility that it represents superimposition of normal fibroglandular tissue, and so it would not be appropriate to jump straight to biopsy.

D. BI-RADS 4 (Suspicious); Recommend ultrasound-guided biopsy

Explanation: This irregular mass is suspicious and should be biopsied (BI-RADS 4). When a mass is visible on both ultrasound and mammogram, an ultrasound-guided biopsy is usually preferred over a stereotactic biopsy, as the former option is usually more comfortable for the patient and allows for real-time visualization of the target by the performing physician. Additionally, there may be technical challenges in performing stereotactic biopsy on a far posterior mass such as this one.

B. Large rod-like calcifications

Explanation: Large rod-like calcifications, also known as secretory calcifications, are benign calcifications associated with duct ectasia and are almost exclusively seen in post-menopausal women. They are often present in a bilateral diffuse distribution, as seen here. Large rod-like calcifications are thicker and larger than the similar-appearing fine linear or fine-linear branching calcifications, which are considered suspicious.

Note the difference between the large rod-like calcifications and the patient’s separate vascular calcifications shown here:

Also note the far posterior intramammary lymph node in the left image.

B. Silicone implants

Explanation: The extremely high and homogenous density of these implants indicates that they are composed of silicone.

With saline implants, we should be able to see “through” and identify the implant valves.

C. Left breast lower outer quadrant fat-containing mass

Explanation: The fat-containing mass shown below is present in the lower outer quadrant of the left breast.

Mammography is not a sensitive modality to assess for silicone implant rupture, although there is no gross evidence of extracapsular silicone implant rupture on these images. Saline implant rupture is a clinical diagnosis.

A. Rim calcification

Explanation: A rim calcification is composed of a continuous rim of thin (≤ 1 mm) calcification that surrounds a round or oval structure, usually with distinct internal fat density, as is true for this case. This large rim calcification has the typical appearance of fat necrosis, as can be seen in the setting of prior breast trauma or surgery (such as implant placement). Oil cysts or simple cysts (not shown in this case) can also have smaller rim calcifications. Rim calcifications are typically benign.