Breast ImagingE2457. The Many Faces of Cystic Breast Masses: Sonographic Appearances With Multimodal Imaging Correlates
Panigrahi B, Ambinder E, Harvey S. Johns Hopkins Hospital, Baltimore, MD
Address correspondence to B. Panigrahi (email@example.com)
Background Information: Cystic breast masses are commonly encountered and can herald both benign and malignant pathology findings. Ultrasound is the imaging modality of choice in the diagnostic evaluation of such lesions. This purpose of this exhibit is to review commonly encountered benign and malignant cystic breast masses, and distinguish imaging features of both benign and malignant pathology with mammographic and MRI correlates.
Educational Goals/Teaching Points: Sonographic BI-RADS mass descriptors, including shape, orientation, margin, echo pattern, and posterior features, will be reviewed. Several benign cystic breast masses including simple cysts, galactoceles, hematomas, papillomas, fat necrosis, abscesses, and epidermal inclusion cysts will be reviewed. Finally, malignant cystic breast masses including ductal carcinoma in situ, invasive ductal carcinoma, papillary breast carcinoma, adenoid cystic carcinoma, and metastases (lung, ovarian) will be reviewed.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques: Cystic breast masses contain anechoic components with increased posterior through-transmission on ultrasound. On mammography, cystic masses tend to have low-to-equal density. On MRI, cystic masses tend to have high T2 and low T1 signals, depending on protein or hemorrhagic contents. Many cystic masses also contain solid components. Multiple imaging features can help distinguish benign from malignant pathology findings. Benign cystic masses have oval or round shape, parallel orientation, and circumscribed margins. Simple cysts may appear and regress over time. Galactoceles contain fat-fluid levels within the cyst. Acute hematomas may initially have low echogenicity that organizes over time with formation of echogenic septations. Epidermal inclusion cysts have a lamellated, hypoechoic appearance with diffusion restriction on MRI. Partly solid, partly cystic masses can also be benign. Cystic papillomas are identified within a duct, often with a vascular stalk. Fat necrosis has a variable sonographic appearance and may present as a cystic mass with mural nodularity, and should be interpreted in conjunction with mammographic findings. Abscesses are hypoechoic fluid collections surrounded by echogenic, vascular rims. Malignant cystic masses tend to be irregular in shape, without parallel orientation, and without circumscribed margins. Solid components are often present within malignant masses and are hypoechoic, irregular, and with internal vascularity. Sonoelastography demonstrates hard tissue, and possible architectural distortion may be seen around the mass. MRI often demonstrates washout kinetics.
Conclusion: Cystic breast masses are seen in both benign and malignant pathology findings. Understanding their ancillary imaging characteristics is vital to reduce unnecessary biopsies of benign pathology findings and to not dismiss potentially suspicious features of malignant pathology findings.