381P - P16INK4 over-expression, early stages, keratinization, and surgical margin-free status are associated with better prognosis of oral squamous cell carcinoma (OSCC)

Background

Oral squamous cell carcinoma (OSCC) is highly prevalent in South-East Asia including Indonesia. Recurrence and early mortality in OSCC patients cause significant health burden. Subclassification of patients with high risks of locoregional recurrence and early death is beneficial for planning of treatment intensification and surveillance.

Methods

Formalin-fixed paraffin embedded (FFPE) tissues of OSCC were immuno-stained and analyzed for p16 expression. Semi-quantitative German scoring system for p16 was used. Risk factors and clinical parameters of OSCC patients were collected and compared to identify factors associated with recurrences and overall survival.

Results

OSCC recurrences and mortality were observed in in 82% and 78% patients (N=60) after a median follow-up of 32 months. Larger tumor size (T3 and T4) was significantly associated with both recurrences and mortality (OR = 3.967,95% CI = 1.007-15.618 and OR = 5.885, 95% CI = 1.541-22.47, respectively). Positive p16 staining was observed in 31% of tumors. Patients with p16 -positive expression were significantly associated with longer recurrence-free and overall survivals (medians of recurrence-free survivals were 31.2 vs 19.0 months, P=0.038 and overall survivals were 39.0 vs 28.8 months, P=0.048; respectively). Other clinical variables including early stages, negative cervical nodes, non-keratinizing tumors, and negative surgical margin status were significantly associated with longer recurrence-free and survivals (log-rank tests, P<0.05).

Conclusions

P16 -positive staining, early stages, positive cervical lymph node infiltration, and positive surgical margins are associated with better prognosis in OSCC patients. The study emphasizes the importance of early detection and the potential use of p16 and other clinical markers as prognostic markers in OSCC patients.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

S. L. Anwar.

Funding

Universitas Gadjah Mada.

Disclosure

All authors have declared no conflicts of interest.