Neutrophil lymphocyte ratio (NLR) change after systemic treatment as a predictive factor of cancer specific survival in stage IV breast cancer.

Abstract

29 Background: Inflammatory response exacerbates mechanisms linked to tumor growth and dissemination. As an index of systemic inflammatory status, neutrophil lymphocyte ratio (NLR) may be a predictive biomarker of both prognosis and response to therapy. We evaluated initial pre-treatment NLR and post-treatment NLR change to assess whether initial and change in NLR would be predictive of disease outcome in stage IV breast cancer patients. Methods: This study included 250 stage IV breast cancer patients diagnosed at Asan Medical Center between 1997 and 2012. The NLR was calculated from the differential count by dividing neutrophil percentage by lymphocyte percentage. All initial (pre-treatment) NLR was evaluated at the first visit day in Asan medical center. Post-treatment NLR was obtained at the first follow-up visit at the outpatient department after first treatment (chemotherapy first: about after 3weeks/endocrine therapy: after 3~6 months). The initial (pre-treatment) NLR was divided by quartile, and the NLR change was calculated by dividing post-treatment NLR by pre-treatment NLR. If the value was ≥ 1.2, NLR change was increased; if not, it was not changed or decreased. We evaluated prognostic value of NLR by comparison with Cancer Specific Survival (CSS). Results: When comparing pre-treatment NLR and post-treatment NLR, the NLR was increased in 85 patients (34%) and stationary or decreased in 165 patients (66%). There was no significant difference between two groups in baseline characteristics. On the other hand, in CSS, the difference between two groups are shown, but does not have statistical significance (log rank p = 0.052). The 1, 3, 5 year CSS rate was 78.8%, 35.7%, 20.5% in increased NLR group, and 87.1%, 49.3%, 26.9% in the other group. Multivariate analysis suggested that increased NLR change (Post/Pre NLR ≥ 1.2) had statistical significance as prognostic factor of stage IV breast cancer patients after treatment (HR = 1.750, 95% CI 1.130-2.709, p-value = 0.012). Conclusions: After start of treatment, increased NLR can be correlated with poor cancer specific survival in stage IV breast cancer. The NLR change might be an index of response of systemic treatment.