Triple Negative Apocrine Carcinomas as a Distinct Subtype of Triple Negative Breast Cancer: A Case-control Study

Clin Breast Cancer. 2018 Oct;18(5):e773-e780. doi: 10.1016/j.clbc.2018.02.012. Epub 2018 Mar 2.

Abstract

Background: Invasive triple negative apocrine carcinoma (TNAC) of the breast is a rare type of triple negative breast cancer. Several studies reported significantly distinct prognosis for TNAC when compared with most of the non-apocrine triple negative (NATN) tumors. This is a case-control study reporting onoutcomes from our long-term single-center experience.

Patients and methods: We analyzed the clinicopathologic features of a series of 46 TNAC tumors treated in a 15-year period. Tumor characteristics and outcomes have been compared with a homogeneous control series of 43 NATN tumors treated during the same follow-up period. Local relapse-free survival (LRFS), distant metastases-free survival (DMFS), and overall survival (OS) have been evaluated.

Results: LRFS in the TNAC group was 85% and 78% at 5 and 10 years, respectively. LRFS in the NATN group was 90% and 79% at 5 and 10 years, respectively (hazard ratio [HR], 1.14; 95% confidence interval [CI], 0.41-3.19; P = .80). DMFS in the TNAC group was 85% and 85% at 5 and 10 years, respectively. DMFS in the NATN group was 85% and 75% at 5 and 10 years, respectively (HR, 0.39; 95% CI, 0.14-1.08; P = .071). OS in the TNAC group was 86% and 83% at 5 and 10 years, respectively. OS in the NATN group was 86% and 63% at 5 and 10 years, respectively. OS was significantly better in the TNAC group (HR, 0.45; 95% CI, 0.20-0.99; P = .049).

Conclusions: TNAC seems to represent a distinct group of triple negative breast cancer, characterized by a favorable long-term outcome when compared with NATN tumors.

Keywords: Apocrine tumor; Breast carcinoma; Case-control; Triple negative; Tumor biology.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Apocrine Glands / metabolism
  • Apocrine Glands / pathology*
  • Biomarkers, Tumor / metabolism
  • Case-Control Studies
  • Female
  • Humans
  • Middle Aged
  • Odds Ratio
  • Prognosis
  • Survival Analysis
  • Sweat Gland Neoplasms / metabolism
  • Sweat Gland Neoplasms / pathology*
  • Sweat Gland Neoplasms / therapy
  • Triple Negative Breast Neoplasms / metabolism
  • Triple Negative Breast Neoplasms / pathology*
  • Triple Negative Breast Neoplasms / therapy

Substances

  • Biomarkers, Tumor