Incidence and outcome for patients with occult lymph node involvement in T1 and T2 oral squamous cell carcinoma: a prospective study

BACKGROUND: The evidence base to inform the decision making process in patients with early stage oral cancer and a clinical and radiological N0 neck remains insufficient to answer the question when it is safe to “watch and wait” and when to proceed with a selective neck dissection. METHODS: A total of 327 consecutive cases of histopathologically staged T(1–2), N(0–1) and M(0), but clinically N(0,) squamous cell carcinoma of the tongue were prospectively analysed. Univariate and multivariate analyses were used for statistical analysis and are represented as Kaplan-Meier analyses or Cox proportional hazard regression analysis. RESULTS: In 61 patients (18.65%) lymph node involvement was found in the histopathological processing. The mean survival of all patients was 73.3 ± 48.6 months. The 2-year and 5-year overall survival rates of all patients were 87.5% and 68.4%, respectively. The 2-year and 5-year survival rates for stage N(0) were 89.1% and 70.7% compared to 83.3% and 62.9% in N(1) situations. The 2-year and 5-year survival rates for stage T(1) were 87.9% and 73.6% compared to 87.2% and 65.3% in stage T(2), respectively(.) The time to recurrence in stage N(0) was 35.1 ± 30.5 months compared to 25.63 ± 24.6 months in cases with N(1) disease. Stage T(1) was associated with a time to recurrence of 38.1 ± 33.9 months compared with 27.2 ± 22.7 months in patients classified T(2). Variables found to be strongly associated with survival in the univariate analysis included older age, higher tumour and N stage, and grading. Age, tumour stage (p = 0.011, 95% CI, 1.09 to 2.0), nodal stage (p = 0.038, 95% CI, 1.02 to 2.07), and recurrence were independently and significantly associated with survival in the multivariate analysis. CONCLUSIONS: This confirms a high overall disease free survival for patients with T1 and N0 treated with single modality surgery and in common with the literature confirms the poor impact on prognosis of the N positive neck.