Deciphering the Predictive Utility of N-telopeptide (NTx) and C-telopeptide (CTx) for Early Bony Invasion in Oral Squamous Cell Carcinoma (OSCC)

BACKGROUND: Early bony invasion in oral squamous cell carcinoma (OSCC) often remains undetected by conventional CT imaging. Bone turnover markers like N-telopeptide (NTx) and C-telopeptide (CTx) may serve as sensitive biomarkers for subclinical bone involvement. OBJECTIVE: To evaluate the potential of serum NTx and CTx levels as diagnostic markers for early bony invasion in OSCC patients whose CT scans showed no radiological evidence of bone involvement. METHODS: A prospective observational study was conducted on 50 OSCC patients with negative CT reports for bone invasion. Serum NTx and CTx levels were measured using ELISA. Based on biomarker levels, patients were categorized into two groups: Group A (elevated NTx and/or CTx) and Group B (normal levels). Statistical comparisons, ROC curve analysis, and logistic regression were employed to assess the diagnostic potential of these biomarkers. RESULTS: Group A (n = 25) showed significantly elevated levels of serum NTx (mean ± SD: 20.4 ± 4.1 nM BCE) and CTx (860 ± 130 ng/L) compared to Group B (NTx: 11.5 ± 2.9 nM BCE; CTx: 540 ± 110 ng/L), with p < 0.001. ROC analysis (receiver operating characteristic) revealed AUCs ( area under the curve) of 0.902 for NTx and 0.928 for CTx, suggesting excellent diagnostic accuracy. Logistic regression confirmed serum NTx and CTx as independent predictors of probable microinvasion. A subgroup analysis based on tumor histopathology revealed NTx to be more sensitive in moderately differentiated tumors, while CTx was more sensitive in poorly differentiated tumors. CONCLUSION: Elevated serum levels of NTx and CTx in OSCC patients with negative CT scans may indicate early bony microinvasion. Incorporating biomarker screening into diagnostic protocols could enhance treatment planning and reduce recurrence.