After treatment begins, an increased neutrophil lymphocyte ratio (NLR) can be correlated with poor disease-specific survival in stage IV breast cancer, according to research presented at the symposium. In addition, the change in NLR might be an index of response to systemic treatment.
Inflammatory response exacerbates mechanisms linked to tumor growth and dissemination, note the study authors, led by Dr. Hae-na Shin of the University of Ulsan, Seoul, South Korea. Used as an index of systemic inflammatory status, the NLR could be a predictive biomarker for both prognosis and treatment response.
To test their hypothesis, Dr. Shin and his colleagues evaluated the baseline NLR prior to beginning treatment, and then the change in posttreatment NLR, to assess if the initial NLR and its change after therapy would be predictive of disease outcome in stage IV breast cancer patients.
The study cohort included 250 women with stage IV breast cancer who were diagnosed at the Asan Medical Center between 1997 and 2012. The NLR was evaluated at their first visit to the center, and a posttreatment NLR was obtained during the first follow-up appointment after patients received their first treatment.
The authors divided the pretreatment NLR by quartile, and the change in NLR was calculated by dividing posttreatment NLR by pretreatment NLR. If the value was greater than or equal to 1.2, NLR change was increased, and if not, then it was considered to be unchanged or reduced. The prognostic value of NLR was then evaluated by comparison with Cancer Specific Survival (CSS).
When comparing pretreatment NLR and posttreatment NLR, the NLR was elevated in 85 patients (34%) but remained the same or decreased in 165 others (66%). There were no significant differences between these two groups in baseline characteristics. However, in CSS, there were differences between the two groups but they did not reach statistical significance (log rank P = 0.052). The 1-, 3-, 5-year CSS rate was 78.8%, 35.7%, 20.5% in the group with an increased NLR, and 87.1%, 49.3%, 26.9% in the other patient group.
Upon multivariate analysis, the results suggested that an increased NLR change (post/pre NLR greater than or equal to 1.2) had statistical significance as a prognostic factor of stage IV breast cancer patients after treatment (hazard ratio, 1.750; 95% confidence interval, 1.130-2.709; P = 0.012).