Abstract P4-07-10: Prognostic Significance of Triple Negative Breast Cancer at Tumor Size 1 Cm and Smaller

Abstract

Abstract Triple negative breast cancer (TNBC) is an independent biomarker of poor prognosis, and associated with a higher predilection for visceral metastasis and early recurrence. However, the prognostic significance of TNBC with a tumor size ≥1 cm is unclear. Patients with primary operable breast cancer with a tumor size ≥1cm were retrospectively collected at Changhua Christian Hospital and National Cheng-Kung University Hospital in Taiwan. Tumors negative for ER, PR, and HER-2, determined by immunohistochemical stain, were classified as TNBCs and compared with tumors with any receptor positivity (non-TNBC) for disease-free survival (DFS) and cancer-specific survival (CSS). From 1995 to 2006, a total of 377 (13%) patients with tumor size ≥1 cm were enrolled from 2835 primary breast cancer patients. The mean age at diagnosis and follow-up time were 50.86 and 4.04 ± 2.83 years, separately. Compared with non-TNBC patients, TNBC with a tumor size ≥1 cm as a whole or in lymph node-positive subgroup was not associated with a poorer 5-year DFS and CSS. In lymph node-negative patients (pT1a-bN0M0), TNBC was associated with a poorer 5-year CSS but not DFS than the non-TNBC group. In multivariate Cox regression hazard analysis, lymph node invasion was the most important cause (hazard ratio: 19.89, 95% CI: 2.18-181.89, P=0.0081) of cancer-specific death. Fig. (a) Disease-free survival (DFS) of TNBC patients versus non-TNBC patients with tumor ≥1 cm. (b) Cancer-specific survival (CSS) of TNBC patients versus non-TNBC patients with tumor ≥1 cm. (c) CSS in node-positive patients with a TNBC versus non-TNBC phenotype. (d) CSS in node-negative patients with TNBC versus non-TNBC. (e) DFS in patients with HR+/ERBB2-, ERBB2+, and TNBC. (f) CSS in patients of HR+/ERBB2- , ERBB2+, and TNBC. (g) CSS in node-positive patients with HR+/ERBB2-, ERBB2+, and TNBC. (h) CSS in node-negative patients with HR+/ERBB2- , ERBB2+, and TNBC. TNBC is very likely an independent risk factor for CSS in small (≥1 cm) node-negative invasive breast cancer. With tumors 1 cm and smaller, lymph node invasion was the single most important prognostic factor. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-07-10.