Grade-lymph node ratio predicts the survival of breast cancer in different molecular types: A surveillance, epidemiology, and end results population-based analysis

The prognostic value and conflicting results of metastatic lymph node ratio (mLNR) on breast cancer have aroused an increasing concern. We aimed to evaluate the imperative of mLNR classification and prognostic factors in breast cancer with molecular subtypes. This study uses the database of surveillance, epidemiology, and end results (SEER) to investigate the imperative for reliable mLNR classification and critical prognostic factors in breast cancer with different molecular subtypes. The prognostic characteristics for disease-specific survival (DSS) of breast cancer were investigated in the SEER cohort (n = 3651). mLNR (P = .017) and histology grade (P < .001) were independent factors. A novel grade-lymph node ratio (G-R) staging system was proposed for breast cancer prognosis. The receiver operating characteristic curves revealed that the G-R staging system had an accurate 1-, 3-, and 5-year DSS prediction. Further stratification analysis with molecular subtypes of breast cancer (Luminal and TNBC) first proved robust prognostic values of the G-R staging system among molecular subtypes. The current population-based cohort demonstrated the capacity of mLNR serving as a critical prognostic factor. Also, G-R staging system has the potential to be regarded as reliable classification for breast cancer patients with different molecular subtypes.