Lymph Node Ratio Assessment of Brain Metastasis in EarlyBreast Cancer Cases

Background: Ten to 30% of early breast cancer (EBC) patients develop brain metastasis (BM) during theirfollow-up. In this study, we aimed to evaluate importance of the lymph node ratio (LNR) in development ofBM in EBC cases. Materials and
Methods: Ninety patients whom had axillary metastases in lymph nodes attheir initial diagnosis and developed BM during 5-year follow-up were detected in 950 EBC patients. LNRvalues were calculated for all patients and after categorization into 4 molecular sub-types as luminal A, luminalB HER-2 (+), HER-2 overexpressing and basal- like. Comparison was with control group patients who hadsimilar characteristics.
Results: In the comparison of all molecular sub-types of LNR, 54.9% and 28.4% valueswere found in patients with and without BM respectively (p<0.001). In the comparison of the LNR with controlgroups, a statistically significant differences were found with luminal A with BM (p=0.001), luminal B HER-2(p=0.001), HER-2 overexpressing (p=0.027) and basal-like groups (p<0.001). In the evaluation of patients withBM, the highest ratio was found in the basal-like group (67.9%) and there was a statistically significant differencebetween this group and the others (p=0.048).
Conclusions: EBC patients developing BM within 5 years followuphad significantly higher LNRs for all molecular sub-types, especially in the basal-like group. Larger scalestudies are now needed for evaluating LNR prognostic importance for EBC regarding BM development.