Natural history and patterns of recurrence of tongue tumours

Summary This retrospective study comprises 226 patients with squamous cell carcinoma of the tongue treated at Canniesburn Hospital, Glasgow between 1980 and 1996. The male:female ratio was 1.2:1 and the average age was 64 years. The ratio of anterior 2/3 to posterior 1/3 tongue lesions was 1.8:1. A total of 23% of patients were clinically staged as T1, 50% were T2 and 27% were T3/T4. At presentation 156 patients (69%) had a clinically negative neck, while 110 patients (49%) had a neck dissection at the time of treatment of the primary. A comparison between the clinical and pathological T and N stages highlighted the difficulties of clinical TNM staging with upstaging of the primary T stage in 21% of patients and downstaging in 6% and upstaging of neck disease in 36% and downstaging in 7.7%. The incidence of clinically occult disease in the neck was 41% including six patients (4.5%) with occult disease in the contralateral neck. Despite advances in treatment, this series has shown no significant improvement in survival over the 17-year study period. The determinant 5-year survival rates by the Kaplan-Meier method were pT1: 79%, pT2: 52%, pT3/4: 35% and overall 51%. In total 48% of patients died of disease directly related to their tongue cancer and this included 8% with systemic failure. Loco-regional failure remains the major problem with tongue cancer accounting for death in 35%. The understanding of the natural history of tongue tumours as a separate entity from other intraoral squamous cell carcinomas should allow us to formulate different strategies for its treatment in the future.