Since lymph node metastasis has critical role in adjuvant chemotherapy decision-making, defining predictive markers may prevent unnecessary and potentiallytoxic treatment. We evaluate the potential role of preoperative age, neutrophil/lymphocyte ratio (NLR), and systemic immune-inflammation index (SII) based on neutrophil, lymphocyte, and platelet counts as predictive markers of lymph node metastasis in patients with operable colorectal adenocarcinoma.
We retrospectively evaluated 349 patients with pathologically confirmed colorectal adenocarcinoma who underwent curative resection at our institution between January 2010- January 2016. SII was defined as neutrophil*platelets/lymphocytes. NLR and SII were calculated using laboratory data before 15 days or less before surgery. We analyzed the correlations between the preoperative NLR, SII, and age and lymph node metastasis in patients with M0 disease. The cut off values for SII and NLR to predict lymph node metastasis were determined with receiver operating curves (ROC) analysis.
The median age was 63 (range: 25-90). Metastatic lymph nodes were present in 185 (53.0%) of the group (N+ patients). Our analysis revealed that preoperative NLR, SII, and age were predictive factors of lymph node metastasis. Of those 268 (76.8%) patients had high SII (≥500)and 259 (74.2% ) had high NLR (≥2).Our analyses revealed that high SII (p = 0.02), high NLR (p = 0.04) and younger age (
The SII, NLR, and age were predictive indicators of lymph node metastasis. Because the risk of lymph node metastasis is lower in older patients with low SII and NLR,sufficient lymph node sampling (more than 12 lymph nodes dissection) may prevent unnecessary adjuvant chemotherapy in low risk patients. Their clinical utility should be validated in further studies.
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All authors have declared no conflicts of interest.