Noninvasive surface-enhanced Raman spectroscopy outperforms combined positive score in predicting sensitivity to neoadjuvant immunotherapy in head and neck squamous cell carcinoma

Background

Head and neck squamous cell carcinoma poses a formidable treatment challenge owing to its complex anatomy and essential functions of the organs involved. Neoadjuvant immunotherapies, particularly PD-1 inhibitors, have shown promise in improving patient outcomes. Nevertheless, the ability to accurately predict which patients will benefit from neoadjuvant immunotherapy continues to be a significant hurdle.

Methods

We investigated 46 patients diagnosed with head and neck squamous cell carcinoma. Combined positive score was assessed before treatment. Serum samples were collected both before and after neoadjuvant immunotherapy, and subsequently analyzed utilizing surface-enhanced Raman spectroscopy.

Results

Significant differences in Raman spectral peaks were observed between the partial response and stable disease groups before treatment, particularly in the regions of 516–525 cm⁻¹, 1240–1400 cm⁻¹, 1600–1636 cm⁻¹, and 1647–1680 cm⁻¹. These peaks represent different cancer-related biochemical components, including protein and nucleic acid vibrations, disulfide bonds, amide III bands, CH2/CH3 deformations, and amide I bands. Principal Component Analysis-Linear Discriminant Analysis and Receiver Operating Characteristic analysis demonstrated that surface-enhanced Raman spectroscopy exhibited remarkable sensitivity and specificity, surpassing the combined positive score in assessing patient responses to neoadjuvant immunotherapy.

Conclusion

Surface-enhanced Raman spectroscopy offers significant potential to surpass the conventional combined positive score in predicting responses to neoadjuvant immunotherapy.