Invasive lobular carcinoma: sonographic appearance and role of sonography in improving diagnostic sensitivity.

PURPOSE

To characterize the ultrasonographic (US) appearance of invasive lobular carcinoma (ILC) and to assess the potential role of US in the earlier detection of ILC.

MATERIALS AND METHODS

US scans in 19 patients with ILC were retrospectively studied for the presence of a mass, characteristics of the margins, internal echogenicity, and attenuation effects.

RESULTS

US showed masses in 13 of the 19 patients (68% sensitivity). Irregularly marginated masses with heterogeneous internal echoes and acoustic attenuation were present in seven patients. A variety of US findings, mimicking a benign lesion, were noted in the other six patients. US sensitivity in the detection of small cancers (< 1 cm) was 25% (one of four patients). Mammographic sensitivity in the detection of ILC in this series was 89% (17 of 19 patients).

CONCLUSION

ILC has a variety of US appearances. US was insensitive and nonspecific in the diagnosis of ILC, especially for small cancers. A negative US result should not deter surgical biopsy if indicated by mammographic findings or clinical findings.