[Clinical characteristics and prognosis of triple-negative breast cancer: a report of 305 cases]

Triple-negative breast cancer is defined by a lack of expression of estrogen receptor, progesterone receptor, and HER2/neu, and considered to be a clinicopathologic entity with aggressive behaviors and poor prognosis. No satisfactory treatment is available. This study was to analyze the clinical characteristics and prognostic factors of the patients with triple-negative breast cancer.Clinical data of 1,280 patients with histopathologically confirmed resectable breast cancer, treated at Cancer Center of Sun Yat-sen University from Jan. 2000 to Dec. 2004, were analyzed. Of the 1,280 patients, 305 (23.8%) were confirmed to be triple-negative breast cancer. The clinical characteristics, recurrence and survival of the patients were summarized.Triple-negative breast cancer was commonly seen in young patients, with large masses, a high proportion of lymph node metastasis and familial history of breast cancer at diagnosis. By Jun. 2007, the median time of follow-up was 52 months (range, 28-89 months). Of the 1,280 patients, 234 had local recurrence and metastasis, and 94 died. There was no significant difference in local recurrence between triple-negative and non-triple-negative breast cancer patients. However, the occurrence rates of lung metastasis (HR= 4.41, P0.001) and liver metastasis (HR=2.13, P=0.006) were significantly higher in triple-negative breast cancer patients than in non-triple-negative breast cancer patients. The 5-year disease-free and overall survival rates were significantly lower in triple-negative breast cancer patients than in non-triple-negative breast cancer patients (73.7% vs. 80.8%, P=0.025; 88.5% vs. 92.8%,P=0.010). Multivariate Cox regression analysis showed that tumor size and lymph node state were prognostic factors of triple-negative breast cancer patients.Nearly one fourth of breast cancer patients in China are triple-negative breast cancer patients. These patients are usually young, with large masses, lymph node metastasis, and family history of breast cancer. Lung metastasis and liver metastasis may be the main reason of poor prognosis of triple-negative breast cancer.