Metaplastic Breast Carcinoma Versus Triple-Negative Breast Cancer

Abstract

Metaplastic breast carcinoma (MBC) differs from classic invasive ductal carcinomas regarding incidence, pathogenesis, and prognosis. The purpose of this study was to compare patients with MBC with clinicopathologic and treatment-matched patients with triple-negative breast carcinoma (TNBC) in terms of response to treatment, progression, and survival.Fifty-four patients with MBC and 51 with TNBC, who were treated at Istanbul University, Institute of Oncology, between 1993 and 2014, were included in the study. After correctly matching the patients with 1 of the 2 groups, they were compared to determine differences in response to treatment, disease progression, clinical course, and survival.At a median follow-up of 28 months, 18 patients (17.1%) died and 27 (25.5%) had disease progression. Metaplastic histology was significantly correlated with worse 3-year progression-free survival (PFS) (51 ± 9% vs. 82 ± 6%, P = 0.013) and overall survival (OS) (68 ± 8% vs. 94 ± 4%, P = 0.009) compared with TNBC histology. Patients who received taxane-based chemotherapy (CT) regimens or adjuvant radiotherapy had significantly better PFS (P = 0.002 and P < 0.001) and OS (P < 0.001 and P < 0.001) compared with others. In the multivariate analysis, MBC (hazard ratio [HR]: 0.09, P < 0.001), presence of neoadjuvant chemotherapy (NACT) (HR: 12.8, P = 0.05), and metastasis development at any time during the clinical course (HR: 38.7, P < 0.001) were significant factors that decreased PFS, whereas metastasis development was the only independent prognostic factor of OS (HR: 23.8, P = 0.009).MBC is significantly correlated with worse PFS and OS compared with TNBC. Patients with MBC are resistant to conventional CT agents, and more efficient treatment regimens are required.

Comparative prognostic analysis for triple-negative breast cancer with metaplastic and invasive ductal carcinoma

“…However, emerging evidence clearly indicates that TNBC is a heterogeneous disease with a variable prognosis that depends on clinical, pathological and genetic factors. Most TNBCs have been reported to be invasive carcinomas of no special type (ICONST), while a number of other histological types (eg, secretory, adenoid cystic, metaplastic, medullary, and myoepithelial tumours) can also exhibit a TNBC phenotype 6. Specific types of breast cancer might be associated with an extremely good or extremely poor prognosis compared with the prognosis of ICONST with similar biological features at a similar stage 7 8.…”

A large collection of integrated genomically characterized patient‐derived xenografts highlighting the heterogeneity of triple‐negative breast cancer

“…This disease is routinely defined by lack of expression of estrogen receptor (ER), progesterone receptor (PR) and no surexpression of human epidermal growth factor receptor 2 (ERBB2) . Globally, women with TNBC have a poor prognosis, particularly due to the absence of targeted therapy . TNBC is a highly heterogeneous disease in terms of histological features, clinical behavior, drug response and molecular profile .…”

Mesenchymal tumours of the breast and their mimics: a review with approach to diagnosis

“…12,14,17,18 Due to higher stage at presentation, more patients with metaplastic carcinoma undergo mastectomies rather than breast conservation therapy, compared to conventional invasive carcinoma. 1,2,35,37 …”

“…12 Patients tend to present at higher stage and show lower response rates to conventional chemotherapy than other basal-like tumours. 1,2,35,37 Metaplastic carcinoma with chondroid or osseous metaplasia has a reported 5 year survival rate of 20-68%. 2,4,10 Low-grade fibromatosis-like carcinomas and low-grade adenosquamous carcinomas may be associated with better outcome.…”

“…1,2,5,9,35,36 The usual mode of spread is haematogenous, with the most common sites of distant metastasis being lung and brain. Metastases may be composed of glandular and/or mesenchymal elements.…”