Clinical outcome and pattern of recurrence in patients with triple negative breast cancer as compared with non-triple negative breast cancer group

Aim: To compare the clinical characteristics and outcomes in terms of survival, propensity and time of local and distant recurrence for women with triple-negative breast cancer (TNBC) to women with non-triple negative breast cancer (NON TNBC). Materials and Methods : A retrospective cohort study was done with 1,026 breast cancer patients with known receptors and Her2neu status diagnosed between January 2005 and January 2011. Statistical Analysis: Comparison of clinical outcomes between the two groups was done using t-tests for mean and chi square tests for frequencies. For overall and recurrence-free survival Kaplan-Meier survival analyses were done. Results: The mean follow-up time for TNBC was 2.9 years and NON TNBC was 4.1 Years. Among the total 1026 patients, 312 patients (30.4%) had TNBC. Compared with non TNBC, those with TNBC had an increased likelihood of death [27.8% vs. 17.8%, P < 0.0008, > 95% confidence interval (CI)], and distant recurrence (41.48% vs. 33.17%; P = 0.02, C I >95%). Visceral metastasis was high in TNBC which showed Brain metastasis (21.11% vs. 6.18%, P < 0.0002), liver metastasis (15.56% vs. 5.02%, P < 0.0002), lung metastasis (25.19% vs. 10.03%, P < 0.0002); while bone metastasis was higher in NON TNBC group (5.2% vs. 20.55%, P < 0.0002). Conclusions: TNBC have a more aggressive clinical course and adverse outcomes as compared to NON-TNBC, but local tumor size and propensity of local recurrence do not vary significantly with receptor status. Though, chance of visceral metastasis is higher in TNBC, bone metastasis is high in NON-TNBC.