Invasive Lobular Carcinoma Imaging Features and Clinical Detection

RATIONALE AND OBJECTIVES: Mammographic findings and method of detection of 52 cases of invasive lobular carcinoma (ILC), the second most common breast carcinoma, are reported. METHODS: Preoperative mammograms and clinical records of all patients with ILC not associated with a second mammary carcinoma (other than lobular carcinoma in situ) from 1979-1991 at the authors' institution were retrospectively reviewed. RESULTS: Abnormal mammographic findings were present in 48/52 (92%) and included irregular spiculated masses (33/52, 63%), asymmetric densities (7/52, 13%), architectural distortion (5/52, 10%), microcalcifications (2/52, 4%), and well circumscribed masses (1/52, 2%). The mean mammographic diameter was 2.1 cm. The tumor was most often best visualized in the craniocaudal projection. At the time of diagnosis, 54% of women had coexistent suggestive breast physical findings and 35% had metastatic carcinoma in axillary lymph nodes. CONCLUSIONS: The infrequency of microcalcifications in pure ILC may hinder mammographic detection and contrasts markedly with ductal carcinoma. Mammography and breast physical examination play complementary roles in the detection of ILC.