Breast invasive lobular carcinoma: a retrospective clinicopathologic study of 25 cases

Invasive lobular carcinoma (ILC) is the second most common type of invasive breast cancer, having distinct prognostic and biologic implications. As an objective of the present work, we analyzed the clinicopathologic characteristics and prognostic factor of this invasive breast cancer variant. Clinical and morphological data of 25 cases of ILC collected during 2006-2011 were reviewed. Histopathologically, 11 cases were of classic type, and the others were non-classic with solid and histiocytoid subtypes being mostly encountered. Overall the non-classic ILC type was diagnosed in more aged patients (with a median age at onset of 59 years), with a predominance for a more advanced tumor degree differentiation (78.5% as grade 2 and 3), in advanced pTNM stages (50% in stage III and IV), with 50% lymph node involvement and with over 70% ER and Her2 reactivity. Statistically, we found that for the solid variant prevailed a PR+ and Her2- status while in histiocytoid subtype the PR- and Her2+ immunoprofile was most encountered. We conclude that non-classic ILC type represents a distinct entity of invasive breast carcinoma with a worsen prognostic than the conventional ILC type.