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.