Invasive Lobular Carcinoma: Imaging Characteristics, Size at Presentation and Bilaterality.

Aims: Invasive Lobular Carcinoma (ILC) is often described as elusive to standard imaging modalities and usually requiring mastectomy to obtain clear margins. Its reputation of being bilateral has been disputed by most recent studies. The aim of this study is to investigate whether the radiological diagnosis of ILC at first symptomatic presentation is more difficult than that of Invasive Ductal Carcinoma (IDC) in a modern breast clinic; also whether its size, surgical treatment at presentation and bilaterality is different from IDC and its subtypes.Materials & Methods: The radiological codes given to all new symptomatic patients with invasive breast cancer, presenting at the breast clinic of St Mary9s Hospital and undergoing surgery as first treatment, (n=754), were collected prospectively between 1998 and 2005 and final mastectomy rates were also recorded. Histological reports of all synchronous and metachronous bilateral cancers presenting with at least one tumour between 1998 and 2007 were analyzed (n=65).Results: ILC was given suspicious radiological codes as often as IDC (90% vs 93%). On final histology, ILC measured on average 3.6cm compared to 2.5cm for IDC (p Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4015.