It was indicated that highly-expressed (>5.36) hsa_circ_0000199 was associated with large tumor size (diameter > 5 cm) (P=0.010), advanced TNM grade (G3) (P=0.003) and high Ki-67 proportion (>14%) (P=0.012) of TNBC patients, while hardly any statistical significance was discernable among patients of non-TNBC group (all P>0.05). The gene discussed is MKI67; the disease is neoplasm.