Low neutrophil-lymphocyte ratio correlates with extended survival in patients with metastatic breast cancer who achieved clinically complete response following multidisciplinary therapy: A retrospective study.

The prognosis of patients with metastatic or recurrent breast cancer (MBC) is improving as novel treatments are developed. The present study compared the clinical characteristics of patients with MBC with or without a complete clinical response (cCR) and identified the survival-associated factors. This was a retrospective study, which included 171 patients treated for MBC between 2011 and 2017 at the Shiga Medical Center for Adults. Neutrophil to lymphocytes ratios (NLRs) were determined in blood samples. The median follow-up period following diagnosis of MBC was 44 months (range, 0-217 months). A total of 32 patients (18.7%) achieved a cCR. Compared with the non-cCR group, the cCR group had significantly fewer metastases or recurrences (P<0.001), significantly fewer visceral metastases (P<0.001), a significantly lower NLR (P<0.001) and were diagnosed with primary breast cancer at a significantly earlier stage (P=0.003). Prognosis was significantly improved in the cCR group compared with the non-cCR group (P<0.001) and a high NLR (≥19) independently predicted worse survival in a multivariate analysis (P=0.0218; hazard ratio, 1.75; 95% confidence interval, 1.09-2.85). In conclusion, the present study determined that achieving a cCR and having a low NLR are important for the long-term survival of patients with MBC.