Screening value of methylated Septin9 and lymphocyte-to-monocyte ratio in colorectal cancer.

The lymphocyte-to-monocyte ratio (LMR) is an indicator of inflammation in blood routine tests; however, little is known about its screening value in patients with colorectal cancer (CRC). The aim of this study was to explore the screening value of LMR and methylated Septin9 (mSEPT9) in CRC patients. The clinical data of 420 patients with CRC, 61 with adenomatous polyps, and 175 healthy individuals from 2018 to 2022 were retrospectively analyzed, and corresponding predictive nomograms were established. The results showed that the levels of LMR and mSEPT9 in the CRC group were significantly lower than those in the control group (P < .05). Meanwhile, the levels of LMR and mSEPT9 in right-sided CRC were significantly lower than those in left-sided CRC (P < .05). With the progression of CRC from stage I to IV, the levels of LMR and mSEPT9 also decreased gradually, and the levels of mSEPT9 in stages III and IV were significantly lower than those in stages I and II (P < .05). Receiver operating curve (ROC) results showed that mSEPT9 had the highest single diagnostic value for CRC, with an area under curve (AUC) of 0.810. The LMR with mSEPT9 combination showed the best combined diagnostic value for CRC, with AUC of 0.885. When the cutoff values of mSEPT9 and LMR were taken as 43.835 and 3.365, the sensitivity and specificity of this combination reached 82.3% and 84.6%, respectively. Our findings suggest that LMR and mSEPT9 differ in non-tumor group and CRC groups with different subtypes and stages, LMR with mSEPT9 combination can further improve sensitivity, and the novel predictive nomogram for CRC based on LMR and mSEPT9 can be further promoted.