Relationship between low recurrence risk score of 21 gene and distant metastasis of early breast cancer

Objective To investigate the prognostic factors associated with distant metastasis in early breast cancer patients with low recurrence risk score of breast cancer 21 gene detection, hormone receptor positive, HER-2 negative and lymph node negative. Methods The clinical and pathological data of 140 patients with hormone receptor-positive, HER-2-negative and lymph node-negative early breast cancer treated in Henan People’s Hospital from May 2014 to February 2018 were retrospectively analyzed. According to recurrence score (RS) score, the patients were divided into two groups, 74 cases (52.9%) in RS 0-10 group and 66 cases (47.1%) in RS 11-18 group. The clinical and pathological characteristics, treatment and prognosis of distant metastasis, such as tumor size, pathological grade, Ki-67 index and lymphatic vascular invasion were compared between the two groups. Results The median follow-up time of RS 0-10 group and RS 11-18 group was 36 months and 39 months, respectively. There were 5 patients with distant metastasis (1 case in RS 0-10 group and 4 cases in RS 11-18 group). The overall distant metastasis rate of the two groups was 3.6%. The incidence of distant metastasis in breast cancer patients diagnosed at < 40 years old was higher than that in breast cancer patients diagnosed at≥40 years old. The distant metastasis rate of patients diagnosed aged < 40 years old was 2.1%, and that of patients diagnosed aged ≥ 40 years old was 1.4%. Conclusions Hormone receptor-positive, HER-2-negative and lymph node-negative early breast cancer patients with low recurrence risk score of 21 gene have a low rate of distant metastasis after operation. Diagnosed age < 40 may be an important factor affecting distant metastasis. Key words: Early breast cancer; 21 gene detection; Low recurrence risk score; Distant metastasis