Nerve growth factor receptor (p75 NTR) and pattern of invasion predict poor prognosis in oral squamous cell carcinoma

Aims:  To evaluate the expression of p75 neurotrophin receptor (p75^NTR) in oral squamous cell carcinoma (OSCC). The results were related to tumour node metastasis (TNM) stage, World Health Organization (WHO) grade, invasive front grading (IFG) and prognosis.
Methods and results:  Immunohistochemically, the expression of p75^NTR was assessed in 53 T1-T2 OSCCs. Clinical data were recorded prospectively. The end-point was disease-free survival. All tumours expressed p75^NTR, and this expression, both in central/superficial tumour areas and at the invasive front, was associated with poor prognosis ( P  = 0.03 and P  = 0.02) (log rank test). Tumours with marked cellular dissociation (IFG parameter) had more recurrences than tumours with collective tumour cell invasion ( P  = 0.03). In tumours showing both p75^NTR at the invasive front and marked tumour cell dissociation, the average risk of recurrence was increased about 17 times (Cox regression analysis) compared with tumours with low p75^NTR expression and collective invasion. Traditional prognostic systems were of no prognostic significance.
Conclusion:  p75^NTR was expressed in all OSCCs. p75^NTR expression and the pattern of invasion were significantly associated with a poor prognosis in OSCCs, and both were better prognostic factors than traditional prognostic parameters. The combination of p75^NTR expression and the pattern of invasion strongly increased precision in the identification of tumours with poor disease-free survival.