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Clinicopathologic features and prognosis of triple-negative breast cancer in patients 40 years of age and younger in Saudi Arabia.

BACKGROUND AND OBJECTIVES
Triple-negative breast cancer (TNBC) has a poor prognosis and overall survival (OS) compared to other types of breast cancer tumors. However, there is to date no evidence that this is also the case in Saudi Arabia.


DESIGN AND SETTING
Retrospective review of breast cancer patients who were treated from January 2001 to December 2008 (517 patients) at the King AbdulAziz Medical City, Riyadh, Saudi Arabia.


PATIENTS AND METHODS
Patients were selected as TNBC if all three markers of estrogen receptor (ER), progesterone receptor (PR) and the human epidermal growth factor (HER2) tested by immunohistochemistry as negative. They were then age- and stage-matched, and compared with non-TNBC patients to examine differences, if any, in their clinicopathologic features, prognosis and OS.


RESULTS
Twenty-six patients with a follow up time of at least three years were identified as TNBC. Thirty-three patients who were age- and stage-matched were selected as the non-TNBC controls. Clinicopathologic results illustrated significantly more grade 3 tumors (P=.02) and CK 5/6 expression (P<.001) in the TNBC group compared to the non-TNBC group. TNBC patients aged ≤40 years showed a significantly worse prognosis and OS compared to TNBC patients aged >40 years (P=.01), and when compared to the non-TNBC group (P=.04).


CONCLUSION
The incidence of TNBC in our cohort is similar to what has been illustrated in previous studies in Western population. There was no significant difference in 3-year survival between TNBC and non-TNBC groups. However, the aggressiveness of this type of tumor and OS is significantly higher in younger patients aged ≤40 years, compared to those over 40 years of age.