Rapid screening of esophageal squamous cell carcinoma by near-infrared spectroscopy combined with aquaphotomics

Esophageal cancer (EC), the fifth most common cause of cancer-related mortality in China, poses a significant threat to public health. Among the pathological types, esophageal squamous cell carcinoma (ESCC) is predominant, comprising approximately 90 % of cases. Screening is crucial for early detection, diagnosis and treatment, thereby reducing ESCC mortality. This study aimed to develop a rapid, accurate, and cost-effective method based on near-infrared (NIR) spectroscopy combined with aquaphotomics for ESCC screening. NIR spectra were obtained from plasma samples of both healthy controls and ESCC patients. Subsequently, principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were utilized to identify the water matrix coordinates (WAMACS), thereby delineating the water absorption spectrum pattern (WASP) and constructing an aquagram. The results showed that the PLS-DA screening test model demonstrated high accuracy and precision rates of 95.12 % and 97.10 %, respectively, along with sensitivity and specificity rates of 97.10 % and 84.62 %. The area under the curve (AUC) achieved 0.9064. Aquaphotomic analysis revealed that the WASP of the healthy group predominantly exhibited strong absorption in regions indicative of strong hydrogen bonds (1460 nm, 1480 nm, 1494 nm), while the WASP of the ESCC group showed strong absorption in regions associated with strong hydrogen bonds, weak hydrogen bonds and free water, especially the regions of weak hydrogen bonds (1434 nm) and free water (1390 nm) were significantly different from those of the healthy group. The findings indicated that the rapid screening model for ESCC, integrating NIR spectroscopy with aquaphotomics, is both effective and feasible, with the WASP presenting as a potentially valuable biomarker for ESCC screening.