• hamartoma
Management
• BI-RADS Assessment Category 2, benign finding
Pearls and Pitfalls
In the literature, hamartomas have also been designated as fibroadenolipomas and adenolipomas. Hamartomas have been reported in patients with a mean age in the late 30s to early 40s. Clinically, the hamartoma may present as a palpable mass, an incidental finding on mammography, or sometimes as tenderness. Rarely a patient presents with nipple inversion or discharge. If the mammogram is performed first, the lesion can be confidently identified if it contains fat. Generally, this mass is not removed. However, in a series in which the tumor was removed, it has been reported to recur in up to 8% of patients.
Suggested Readings
1. Helvie Mak, Adler DD, Rebner M, et al. Breast hamartoma: variable mammographic appearance. Radiology 1989;170:417–421.
2. Hessler C, Schnyder P, Ozzello L. Hamartoma of the breast: diagnostic observations of 16 cases. Radiology 1978;126:95–98.
3. Jackson FL, Lalani Z, Swallow J. Adenolipoma of the breast. J Can Assoc Radiol 1988;39:288–289.
Case 4
Case History
A 73-year-old professional violinist presents for a screening mammogram. She has a history of a soft mass in the upper outer left breast for more than 20 years.
Physical Examination
• left breast: very soft area of asymmetry in the upper outer quadrant
• right breast: normal exam
Mammogram
Mass
• margin: circumscribed
• shape: round
• density: fat-containing
Associated Findings
• completely fatty encapsulated mass in the upper outer quadrant of the left breast (Fig. 4–1)
Figure 4–1. Right MLO mammogram: There is a large, well-defined radiolucent lipoma. The small nodule that projects in the center of the mass is a lymph node located just medial to the lipoma on the CC view.
Ultrasound
Frequency
• 11.5 MHz
Mass
• margin: well defined
• echogenicity: isoechoic
• retrotumoral acoustic appearance: no shadowing
• shape: ellipsoid (Figs. 4–2 and 4–3)
Figure 4–2. Left radial breast sonogram: Combined images of the upper outer quadrant show the margins of the lipoma (arrows). The mass created by the lipoma pushes the thin hyperechoic parenchymal lines (representing lobular regression) superiorly.
Figure 4–3. Left radial breast sonogram: Sonogram is in a normal portion of the same breast as Figure 4–2. This image is intended to demonstrate the normal architecture of the fatty breast parenchyma. F, fatty breast parenchyma; C, Cooper's ligaments; M, chest wall muscle.
Pathology
• lipoma
Management
• BI-RADS Assessment Category 2, benign finding
Pearls and Pitfalls
1. Mammographic fat-containing masses are benign so sonographic examination is generally not necessary. However, occasionally, a patient is referred for sonography for a palpable fatty mass that has not been mammographically characterized. In these cases it is important to be familiar with the sonographic appearance of fatty masses and recommend mammography to confirm the benign identity of the mass.
2. Sonographically, lipomas are generally oval and well defined. They are hypoechoic, isoechoic, hyperechoic, or heterogeneous in echogenicity. In a fatty breast, isoechoic tumors are sometimes difficult to identify. However, this case emphasizes that lipomas do not have the same internal architecture as normal fatty parenchyma. The echogenic lines within the lipoma do not follow a normal pattern of lobular regression.
Suggested Readings
1. Fornage BD, Tassin GB. Sonographic appearance of superficial soft tissue lipomas. J Clin Ultrasound 1991;19:215–220.
Case 5
Case History
A 73-year-old woman presents for screening mammogram.
Physical Examination
• normal exam
Mammogram
Mass (Fig. 5–1)
• margin: circumscribed
• shape: oval
• density: fat-containing
Figure 5–1. The right breast is dominated by a fat density mass. This mammographic appearance is diagnostic of a lipoma. (A). Right MLO mammogram. (B). Right CC mammogram.
Pathology
• lipoma
Management
• BI-RADS Assessment Category 2, benign finding
Pearls and Pitfalls
Lipomas are common benign breast masses. The average age of presentation is in the late 40s or early 50s. Generally, these tumors are unilateral. In 3% of cases, bilateral lipomas are present. Histologically, these tumors are composed of mature lipocytes surrounded by a capsule.
Suggested Readings
1. Tavassoli FA. Mesenchymal lesions. In: Tavassoli FA, Fattaneh A, eds. Pathology of the Breast. 2nd ed. Stamford: Appleton and Lange; 1999:675–729.
Case 6
Case History
A 48-year-old woman, status post lumpectomy 16 months ago. She now has a small palpable lump in her lumpectomy site. She is initially studied sonographically. Upon discovery of a sonographic nodule, mammographic examination has been performed.
Physical Examination
• left breast: 8 mm lump at the 6:00 position within the scar of her lumpectomy site
• right breast: normal exam
Mammogram
Mass (Fig. 6–1)
• margin: circumscribed
• shape: oval
• density: fat-containing
Figure 6–1. Left MLO magnification spot mammogram: In the region of the patient's lumpectomy site there is an oval radiolucent nodule.
Ultrasound
Frequency
• 13 MHz