Comparison of hair medulla from lymph node metastasis and non-lymph node metastasis gastric cancer patients using synchrotron radiation infrared microspectroscopy

Lymph node metastasis often occurs in gastric cancer, hence it is important to explore new methods for diagnosing lymph node metastasis before surgery. In this study, synchrotron radiation infrared (SR-IR) microspectroscopy was used to compare hair medulla from lymph node metastasis and non-metastasis gastric cancer patients. Peak-area ratios indicated that significant alterations might occur in lipids, proteins and nucleic acids after lymph node metastasis. Discriminant analysis was implemented on the basis of peak-area ratios and obtained the following results: the sensitivity was 80.56%, the specificity was 82.76%, the positive predictive value was 85.29% and the accuracy was 81.54%. This study showed that biomacro-molecules in hair medulla were influenced by lymph node metastasis, indicating that IR spectra of hair medulla may be potentially used to diagnose lymph node metastasis before gastric cancer surgery.