Determining the Unique Radiological Features of Lobular Breast Cancer on Imaging in Histopathologically Proven Cases – Our Institutional Experience

BACKGROUND Lobular breast carcinomas have always been a diagnostic challenge, over the years, to the radiologist. They are one of the most commonly missed lesions on breast cancer screening checks, due to their varied presentation. We wanted to provide a concise and practical approach to characterise their morphology and presentation on mammography and ultrasound. METHODS A retrospective study was done for four years and a total of 699 patients with histopathologically proven breast cancer were chosen. Those patients with invasive lobular carcinoma (N = 56) and invasive ductal carcinoma (N = 538) were segregated and 50 cases from each group were selected randomly. RESULTS On mammography, an irregular, high-density mass was the most common presentation of both lobular (68 %) and ductal (86 %) carcinomas. Presentation as focal asymmetry (28 %) was significantly more prevalent in lobular breast carcinomas. Sonographically, an architectural distortion (30 %) and non-parallel orientation (28 %) was predominantly seen in invasive lobular carcinomas (ILCs). Mass (88 %) with micro lobulated (34 %) or angular (22 %) margins was more in favour of ductal carcinoma. Other general parameters like age at presentation, positive family history, multifocality, bilaterality, tumour size and lymph nodal involvement were not significantly different between both the groups. CONCLUSIONS A careful analysis of digital breast tomosynthesis and ultrasonography, keeping in mind all the clear differentiating features, along with experience in the field, will dramatically increase the early detection of lobular breast cancers. KEY WORDS Invasive Lobular Carcinoma (ILC), Invasive Ductal Carcinoma (IDC), X-Ray Mammography, Sono-Mammography