Colorectal cancer related mortality is still high. The widespread use of colonoscopy, surgical advancements, and standardized use of chemotherapeutic agents has increased survival rates in metastatic cases. Inflammation is the main etiological factor in a variety of cancers. Plateletto- lymphocyte ratio (PLR), one the most studied biochemical parameters, has been shown as a poor prognostic factor. In this study, our aim was to determine the predictive value of PLR on liver metastasis and lymph node positivity in colorectal patients.
The data of patients who were diagnosed with colorectal cancer and underwent surgery between March 2010 and September 2016 were analyzed retrospectively. Demographic characteristics, preoperative PLR, intraoperative findings, and tumor-node-metastasis stages were recorded. Patients with liver metastasis comprised group 1a and those without liver metastasis were group 1b; patients were also sorted into groups 2a and 2b based on lymph node positivity or negativity, respectively.
A total of 152 patients were included in the study and the male/female ratio was 1.53. Most of patients had rectosigmoid junction tumors. Eight patients had familial history of colorectal cancer and 66 patients had comorbid conditions. Eight patients had early 30-day mortality. Thirty-one patients had liver metastasis. Patients with liver metastasis (group 1a) had significantly higher PLR values when compared to group 1b (p<0.001). When age, gender and comorbid diseases were analyzed together, group 1a had significantly higher PLR values (p<0.001). The cut-off value of the PLR for liver metastasis was 194.7, giving a sensitivity of 74.2% and specificity of 72.7%. Patients with lymph node positivity (group 2a) had significantly higher PLR (p<0.001) than patients in group 2b. The cut-off value of the PLR for lymph node positivity was 163.95, giving a sensitivity of 56.8% and specificity of 56.3%.
As an inexpensive and feasible parameter, PLR could be useful for predicting liver metastasis and even lymph node positivity of colorectal cancers.
Keywords: Platelet, lymphocyte, colon carcinoma, liver metastasis