Tumor characteristics and the clinical outcome of invasive lobular carcinoma compared to infiltrating ductal carcinoma in a Chinese population.

Background: We sought to compare the baseline demographics, standard pathologic factors and long-term clinical outcomes between ILC and infiltrating ductal carcinoma (IDC) using a large database.
Methods: Clinicopathologic features, overall survival (OS), and recurrence/metastasis-free survival (RFS) were compared between 2,202 patients with IDC and 215 patients with ILC.
Results: ILC was significantly more likely to be associated with a favorable phenotype, but the incidence of contralateral breast cancer was higher for ILC patients than for IDC patients (8.4% vs. 3.9%; P=0.001). The frequencies of recurrence/metastasis (P = 0.980) and death (P = 0.064) were similar among patients with IDC and patients with ILC after adjustment for tumor size and nodal status. The median follow-up was 42.8 months.
Conclusions: Chinese women with ILCs do not have better clinical outcomes than their counterparts with IDC. Management decisions should be based on individual patient and tumor biologic characteristics, and not on lobular histology.