Invasive Lobular Carcinoma of the Breast. A Clinicopathologic Study of 1,200 Cases
I Alvarado-Cabrero, R Valencia-Cedillo, J Castro-Garcia, G Picon-Coronel, S Barroso-Bravo. Mexican Oncology Hospital, Mexico, DF, Mexico
Background: Invasive Lobular Carcinoma (ILC) account for approximately 5% to 15% of invasive breast carcinomas and are the second most common type. As such, most clinical research conclusions are driven by the outcome of patients with Invasive Ductal Carcinomas(IDC), which dominates the breast cancer population. The goal of this study is to investigate the clinical and pathological features of ILC.
Design: From 1998 to 2008, 5200 patients with invasive breast cancer were identified at our Institution. The clinical and biological features of the patients with IDC were compared with those patients with ILC. The median follow-up period was 72 months. Clinical variables were compared using Chi square and Fisher´s exact tests.
Results: One thousand and two hundred (23%) tumors were classified as ILC and 4000 (76.9%) as IDC. In comparison with IDC, ILC was significantly more likely to occur in older patients, to be larger in size (2cm vs 4cm, respectively), to be estrogen and progesterone receptor positive and to be HER-2 negative (P:<.01). Most ILC cases were grade 2 tumors(80%), while a small proportion of tumors were either grade 1 or 3 tumors(10% each). The incidence of contralateral breast cancer was higher for ILC patients than for IDC patients (P: < 0.1). The 5-year overall survival was 70.2% for ILC and 68.3% for IDC (P:0.66).
Conclusions: ILC is a distinct entity of breast cancer, on the other hand, patients with this type of tumor do not have better clinical outcome than patients with IDC.
Tuesday, March 23, 2010 9:15 AM
Platform Session: Section C, Tuesday Morning