Prediction of late recurrence in patients with breast cancer: elevated neutrophil to lymphocyte ratio (NLR) at 5 years after diagnosis and late recurrence.

BACKGROUND: Late recurrence accounts for nearly half of the recurrences in estrogen receptor (ER)-positive breast cancer and decreases post-recurrence survival in patients with ER-negative breast cancer. Clinicopathological factors and multigene assays have been used for various purposes but their prognostic capacity for late recurrence was limited. This study aimed to determine whether neutrophil to lymphocyte ratio (NLR) taken after primary treatment can be a feasible prognostic factor for late recurrence. METHODS: Patients who were diagnosed with primary breast cancer and completed planned treatment were enrolled; data were retrospectively collected from the Wonju Severance Hospital database of Yonsei University. RESULTS: 496 patients completed planned treatment for their primary breast cancer. 385 were disease free after 5 years of the primary diagnosis and 330 were enrolled for second-look NLR analysis. NLR analysis performed approximately 5 years after the primary diagnosis categorized patients into high and low risk of late recurrence with p < 0.001 and an elevated NLR was found as an independent risk factor for late recurrence (HR 1.448, CI 1.168-1.795, p < 0.001). CONCLUSION: A clinically valid biomarker to determine late recurrence is urgently needed to prevent patients from treatment extension with little benefit. Elevated NLR is found as an independent prognostic factor for late recurrence and could be utilized as a reliable, easily accessible, and cost-effective test.