Risk factors of recurrence in small-sized, node negative breast cancer in young women: a retrospective study in Chinese population

We aimed to investigate risk factors of local and distant recurrence in small-sized, node negative breast cancer in women <35 years in a Chinese cohort. Between January 1994 and January 2007, 107 patients with pathologically confirmed small-sized ( 1 cm), node negative breast cancer who did not receive neoadjuvant or adjuvant chemotherapy were included. The 5-year recurrence-free survival (RFS) was estimated according to different prognostic variables. With a median time of 60 months (range, 8–60 months) follow-up, local and distant recurrence were observed in 25 cases (23.4%). By univariate analysis, HER-2 positivity, triple negative (TN), and high Ki-67 index ( 14%) were risk factors of a lower RFS (hazard ratio (HR) 6.680, 95% confidence interval (CI) 2.350–18.985, P<0.0001 for HER-2 positive; HR 4.769, 95%CI 1.559–14.591, P=0.006 for TN; HR 6.030, 95%CI 2.659–13.674, P<0.0001 for high Ki-67 index). Patients with grade 3 tumors had a lower RFS (HR 2.922, 95%CI 1.096–7.791, P=0.032) compared with those with grade 1 or grade 2 tumors. By multivariate analysis, HER-2 positivity (HR 10.204, 95%CI 3.391–30.704, P<0.0001), TN (HR 10.521, 95% CI 3.152–35.113, P<0.0001) and high Ki-67 index (HR 10.820, 95%CI 4.338–27.002, P<0.0001) remained risk factors of RFS. In this cohort, HER-2 positivity, triple negative and high Ki-67 index were independent risk factors of RFS in young patients with T1a,bN0 breast cancer. Subsequent pregnancy did not affect RFS.