Research article

Breast cancer subtypes and survival in patients with brain metastases

Byung-Ho Nam^1* , Sun Young Kim^1* , Hye-Sook Han¹ , Youngmee Kwon² , Keun Seok Lee² , Tae Hyun Kim³ and Jungsil Ro²

¹  Center for Clinical Trials, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769, Republic of Korea

²  Center for Breast Cancer, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769, Republic of Korea

³  Center for Proton Therapy, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769, Republic of Korea

author email corresponding author email* Contributed equally

Breast Cancer Research 2008, 10:R20doi:10.1186/bcr1870

Published:	28 February 2008

See related editorial by Grewal and Kesari, http://breast-cancer-research.com/content/10/2/104

Abstract

Introduction

Brain metastases (BM) occur in up to one third of patients with metastatic breast cancer (MBC), whose incidences and prognoses by breast cancer subtypes in BM have not been well delineated.

Methods

Retrospective survival analyses were performed in 126 BM patients from 805 MBC patients treated at the National Cancer Center between August 2001 and April 2006, according to clinical characteristics, breast cancer subtypes, and receipt of trastuzumab. Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth receptor-2 (HER2) statuses were tested by immunohistochemical (IHC) staining, and HER2 FISH analysis conducted for IHC 2+.

Results

The proportion of HER2+/ER- (29% vs 16%) and triple-negative (37% vs 25%) tumors was higher in the 126 BM patients than those without BM. While median survival after recurrence was longer in patients with luminal A disease (median survival of luminal A vs luminal B vs HER2+/ER- vs triple-negative: p = 0.0246; 39.6 vs 27.4 vs 20.9 vs 15.5 months), survival was shorter from BM to death in luminal A and triple negatives (median survival: p = 0.0113; 4.0 vs 9.2 vs 5.0 vs 3.4 months). Receipt of trastuzumab after BM was a significant variable for survival in HER2+ patients. Multivariate analyses identified ER-negative, HER2-negative, or triple-negative, as well as older age, presence of leptomeningeal disease, and three or more extracranial disease sites, as poor prognostic factors for survival after BM.

Conclusion

MBC patients who developed BM had higher proportions of triple-negative and HER2+/ER- tumor status. Triple receptor status is a useful prognostic marker for predicting survival after BM in metastatic breast cancer patients.