Lymph Node Ratio is More Predictive than Traditional LymphNode Stratification in Lymph Node Positive Invasive BreastCancer

Objective: To evaluate the relationships between lymph node ratio (LNR, the ratio of positive lymph nodesin excised axillary lymph nodes) and disease-free survival (DFS) by comparing with traditional absolute positivelymph node number (pN classification) for prediction of breast cancer (BC) progrnosis. Methods and Patients:We retrospectively reviewed patients who received comprehensive therapy in Department of Breast Surgery,Hubei Cancer Hospital, China from Jan 2002 to Dec 2006 (Group A), and Department of Breast and ThyroidSurgery, Renmin Hospital of Wuhan University, China from Jun 2008 to May 2012 (Group B). Patients wereallocated to low-risk (≤0.20), intermediate-risk (> 0.20 but ≤ 0.65), high-risk (>0.65) groups by LNR. The primaryendpoint was 5-DFS.
Results: A total of 294 patients were included in our study. LNR was verified as a negativeprognostic factor for DFS (P= 0.002 in Group A, P< 0.0001 in Group B). Then we found the effects of pN and LNRdelamination on disease-free survival (DFS) had statistical significance (P=0.012 for pN and P=0.031 for LNRstratification in Group A, both of them P<0.001 in Group B). Compared to pN staging, LNR staging displayedsuperior performance in prognosis, the adjusted hazard ratio of recurrence being 2.07 (95%CI, 1.07 to 4.0) forintermediate risk group (P=0.030) and 2.44 (95%CI, 1.21 to 4.92) for high risk group (P=0.013) in Group A.
Conclusions: LNR stratification proved an adverse prognostic factor of DFS in lymph nodes positive invasiveBC using cut-off values 0.20 and 0.65, and was more predictive than traditional pN classification for 5-DFS.