Exploratory Evaluation of Neopterin and Chitotriosidase as Potential Circulating Biomarkers for Colorectal Cancer

Chronic inflammation is demonstrated to play a direct role in carcinogenesis. Our exploratory study aimed to assess the potential added value of two inflammation biomarkers, chitotriosidase and neopterin, in follow-up evaluation of patients with colorectal cancer (CRC). An observational exploratory study was conducted. Patients with CRC and matched controls (1:1, age, sex, and living environment) were evaluated. The patients with CRC (CRC group) and controls were assessed at baseline (before surgical intervention for patients with CRC). Patients with CRC were also evaluated at 1-year follow-up. Significantly more patients with blood group A (54.5% vs. 25.0%) and smokers (50.0% vs. 22.7%) were in the CRC group. The serum values of chitotriosidase and neopterin were higher in CRC patients than in controls, but only neopterin reached the conventional level of statistical significance (p-value = 0.015). The circulating chitotriosidase and neopterin values decreased significantly at 1-year follow-up (p-value < 0.0001). Patients with higher N- and M-stage showed statistically significant higher levels of chitotriosidase and neopterin at baseline and 1-year follow-up (p-values < 0.03). Circulating chitotriosidase levels also showed statistically significant differences regarding baseline and 1-year follow-up on patients with CRC and different differentiation grades (p-values < 0.02). The circulating levels of neopterin significantly decreased at 1-year follow-up, indicating its potential as a prognostic marker. The circulating values of chitotriosidase and neopterin exhibit significant differences in patients with than without recurrences. Our results support further evaluation of chitotriosidase and neopterin as prognostic markers in patients with CRC.

Receiver Operating Characteristic Prediction for Classification: Performances in Cross-Validation by Example

The stability of receiver operating characteristic in context of random split used in development and validation sets, as compared to the full models for three inflammatory ratios (neutrophil-to-lymphocyte (NLR), derived neutrophil-to-lymphocyte (dNLR) and platelet-to-lymphocyte (PLR) ratio) evaluated as predictors for metastasis in patients with colorectal cancer, was investigated. Data belonging to patients admitted with the diagnosis of colorectal cancer from January 2014 until September 2019 in a single hospital were used. There were 1688 patients eligible for the study, 418 in the metastatic stage. All investigated inflammatory ratios proved to be significant classification models on both the full models and on cross-validations (AUCs > 0.05). High variability of the cut-off values was observed in the unrestricted and restricted split (full models: 4.255 for NLR, 2.745 for dNLR and 255.56 for PLR; random splits: cut-off from 3.215 to 5.905 for NLR, from 2.625 to 3.575 for dNLR and from 134.67 to 335.9 for PLR), but with no effect on the models characteristics or performances. The investigated biomarkes proved limited value as predictors for metastasis (AUCs < 0.8), with largely sensitivity and specificity (from 33.3% to 79.2% for the full model and 29.1% to 82.7% in the restricted splits). Our results showed that a simple random split of observations, weighting or not the patients with and whithout metastasis, in a ROC analysis assures the performances similar to the full model, if at least 70% of the available population is included in the study.