Abstract:
Objective To investigate the value of mDixon-Quant imaging combined with blood cell parameters in assessing lymphovascular invasion (LVI) and lymph node metastasis (LNM) in rectal cancer (RC).
Methods Clinical and magnetic resonance imaging (MRI) data were retrospectively collected from 62 patients with pathologically confirmed RC at North China University of Science and Technology Affiliated Hospital from November 2022 to June 2024. We calculated the ratio of blood cell parameters and measured the mDixon-Quant parameters, including fat fraction (FF), R2* value, and T2* value, of the lesions. We compared these metrics across groups and performed multiple Logistic regression analyses to identify risk factors associated with LVI and LNM. Additionally, we calculated the area under the curve (AUC) of the receiver operating characteristic (ROC) to evaluate predictive efficacy. Smooth curve fitting and Spearman correlation analysis were used to evaluate the relationship between imaging and blood cell parameters.
Results The R2* value, neutrophil to lymphocyte ratio (NLR), systemic immune-inflammation index (SII), and systemic inflammatory response index (SIRI) were significantly higher in the LVI-positive group compared to those in the negative group. Similarly, the LNM-positive group showed higher R2* value, FF value, NLR, platelet to lymphocyte ratio (PLR), SII, and SIRI than the negative group, with all differences being statistically significant (P<0.05). R2* and SII were identified as independent risk factors for LVI, with AUCs of R2*, SII, and R2*+SII being 0.752, 0.802, and 0.883, respectively. R2*, FF, and SII were independent risk factors for LNM, and the AUCs of R2*, FF, SII, R2*+FF, and R2*+FF+SII were 0.733, 0.702, 0.778, 0.825 and 0.857, respectively. Correlation analysis indicated a positive relationship between FF and several blood cell parameters, including NLR, monocyte to lymphocyte ratio (MLR), SII, and SIRI (r=0.534, 0.451, 0.353, 0.468, P<0.05).
Conclusions Both mDixon-Quant imaging and blood cell parameters are effective for assessing LVI and LNM status in RC. In addition, the correlation between FF and various blood cell parameters highlights the potential role of abnormal lipid metabolism and inflammatory responses in the development of RC, suggesting new avenues for developing clinically tailored treatment protocols.