Invasive Lobular Carcinoma Has Worse Outcome Compared with Invasive Ductal Carcinoma in Stage IV Breast Cancer with Bone-Only Metastasis

Background: Invasive lobular carcinoma (ILC) is more likely to be bone metastasis than invasive ductal carcinoma (IDC). However, the prognosis for bone metastasis in ILC and IDC is barely known. So, the aim of this study was to investigate the difference of prognosis between ILC and IDC accompany by bone metastasis. Methods: We evaluated the women with bone-only metastasis of defined IDC or ILC, reported to the Surveillance, Epidemiology and End Results program from 2010 to 2016. Pearson's chi-squared test was used to compare the difference of clinicopathologic factors between IDC and ILC. Univariate and multivariate analyses were performed to verify the effects of histological types (IDC and ILC) and other clinicopathologic factors on the overall survival (OS) and cancer-special survival (CSS). Results: Overall, 3647 patients with IDC and 945 patients with ILC met the inclusion criteria and were analyzed in our study. The patients with ILC were more likely to be older, lower histological grade and higher proportion of HR+/HER2- subtype. But less treatment was applied to ILC than IDC, such as surgery of the breast, radiation and chemotherapy. Compared patients with IDC, the patients with ILC showed worse OS (median OS 36 and 42 months respectively, p
Source: Breast Care - Category: Cancer & Oncology Source Type: research