Klin Onkol 2012; 25(3): 188-198. DOI: 10.14735/amko2012188.
Summary
Background: Triple-negative breast cancer (TNBC) represents a heterogeneous group of breast cancers that do not express ER-?, PgR and Her-2 receptors. Generally, these tumors are aggressive and more common in younger women, in which an association of TNBC with mutations in the BRCA1 gene was documented. The aim of our study was to create a representative group of patients with TNBC, which could be analyzed and the data gathered to build basic epidemiological, molecular and clinical characteristics of Czech patients with TNBC. Patients and Methods: We performed basic clinical-pathologic correlations in a group of 335 patients diagnosed and/or treated for TNBC at the Masaryk Memorial Cancer Institute between 2004 and 2009. We also performed immunohistochemical examination of expression of cytokeratin 5/6, cytokeratin 14 and EGFR to identify the ‘basal-like’ subset of TNBC. Results: The median age of patients with TNBC was 56 years, range 25–88 years. A total of 9.25% of TNBC cases were diagnosed in patients under the age of 34, and another 15.22% of cases were in the age group of 35 to 44 years. ‘Basal-like’ carcinomas accounted for 75% of TNBC. We confirmed the aggressive nature of this disease: in the follow-up period we observed a relapse in 25% of patients: 55% of deaths due to disease progression occured within 2 years after diagnosis of the disease. Treatment strategies include chemotherapy, in most cases (88.4%). Chemotherapy was mostly based on regimens with anthracyclines or in combination with taxanes. The most important negative prognostic factors in relation to OS (disease specific OS) were: higher clinical stage (p < 0.0001), pN – positive status (p < 0.0001), high proliferative activity (as measured by Ki-67, cut-off 50%, HR = 0.4740, p = 0.0411) and positive expression of CK5/6 (HR = 0.4274, p = 0.0338). In relation to DFS, the negative prognostic significance was found for these factors: higher clinical stage (p < 0.0001), pN positive status (p < 0.0001), high proliferative activity (Ki-67, cut-off 50%, HR = 0.04993, p = 0.0240). DFS was longer in patients with a higher number of applied cycles of anthracycline-based chemotherapy (> 4 cycles, HR = 1.7273, p = 0.0467). Conclusion: TNBC is an aggressive form of breast cancer, which may occur in patients of all ages, but more frequently in younger patients. Only early detection of disease and intensive treatment gives a high chance of cure. Unfortunately, no reliable predictive factors have been identified so far. Better therapeutic results can be expected from targeted therapy.
