Tubulolobular carcinoma of the breast: clinical, mammographic and sonographic findings

PURPOSE: To determine and quantitate radiologic characteristics of tubulolobular carcinoma of the breast and to report clinical and pathologic findings. MATERIALS AND METHODS: A retrospective review of records of 2872 women who received a diagnosis of breast carcinoma between January 1988 and January 2006 revealed 26 histopathologically proven tubulolobular carcinoma of the breast. Analysis included history; findings at physical examination, mammography, and sonography (US) at the time of diagnosis and in postoperative follow-up, and histopathological results. RESULTS: At physical examination, palpable mass was present in 85% (n=22) of the patients. The mammographic findings were mass in 17 (65%), asymmetric focal density in 2 (8%), architectural distortion in 2 (8%) and negative mammograms in 5 (19%) of the 26 patients. US depicted 25 masses in 24 patients, all of which were hypoechoic, with spiculated (n=13) or microlobulated (n=12) margins. The cancer was clinically occult in 12% (n=3), mammographically occult in 19% (n=5), and radiologically occult in 4% (n=1) of the patients. Histologically, the mean size of the tumor was 1.7cm and 18 (69%) patients were node negative. CONCLUSION: Tubulolobular carcinoma of the breast usually manifests clinically as a firm, immobile mass and mammographically as a spiculated or ill-defined, irregular, isodense mass without microcalcifications. Common findings on sonography include a homogeneously hypoechoic, spiculated or microlobulated mass with posterior acoustic shadowing or normal acoustic transmission. Tubulolobular carcinoma should be included in the differential diagnosis for breast masses with these imaging features.