Incidence and survival trends of lip, intra-oral cavity and tongue base cancers in south-east England

BACKGROUND

Oral cavity cancers are on the increase in the UK. Understanding site-specific epidemiological trends is important for cancer control measures. This study demonstrates the changing epidemiological trends in lip, intra-oral cavity and tongue base cancers in south-east England from 1987 to 2006.

AIM

METHODS

This was a retrospective study using anonymised data obtained from the Thames Cancer Registry (TCR) London. Data were analysed using SPSS v.17 and survival analyses with Kaplan-Meier and Cox regression. Age standardisation of the incidence rates was performed. It was conducted in south-east England, which has an average population of 12 million. The study analysed 9,318 cases (ICD-10 code C00-C06, C14). Kent Research Ethics Committee UK granted ethical approval.

RESULTS

Oral cancers were more common in men, with male: female ratio of 1.6:1. Tongue cancers had the highest frequency at 3,088 (33.1%). Incidence varied with each cancer type. Mean incidence (per 1,000,000) ranged from 2.3 (lip cancer) to 13.8 (tongue cancer). There has been a statistically significant increase in incidence for cancers of the tongue base, other parts of tongue, gum and palate (p<0.001). Median survival time varied by sub-site, with lip cancer having the best median survival time (11.09 years) compared with tongue base cancer (2.42 years). Survival analyses showed worse prognosis for men, older age at diagnosis, and presence of synchronous tumours (p<0.001).

CONCLUSION

There is a rising incidence of tongue and tongue base, gum and palate cancers in south-east England with wide variability in survival. Oral cancer awareness and screening programmes should be encouraged.

A 20-year retrospective study of tonsil cancer incidence and survival trends in South East England: 1987-2006

BACKGROUND

There has been an increasing incidence of tonsil cancer worldwide. Documenting these changes is crucial to cancer prevention and control measures, resource allocation and understanding disease aetiology.

OBJECTIVE

To analyse the changing epidemiology of tonsil cancer in South East England over a 20-year period between 1987 and 2006.

DESIGN

A retrospective, quantitative study using secondary anonymised data obtained from the Thames Cancer Registry, London. Data were analysed using spss v.17 and survival analyses with Kaplan-Meier and Cox regression.

SETTING

This study was conducted in South East of England comprising London, Kent, Surrey and Sussex counties with an average population of 12 million. This population increased from 10.7 to 11.8 million (a 10% increase) between 1987 and 2006.

PARTICIPANTS

All patients with tonsil cancer in South East England registered with the Thames Cancer Registry (ICD-10 code C09) between 1987 and 2006. A total of 1794 patients' data were analysed. Ethical Considerations: Ethical approval was granted by the Kent Research Ethics Committee.

MAIN OUTCOME MEASURES

Data were analysed for demographic trends including gender, age at diagnosis, yearly incidence and survival.

RESULTS

Tonsil cancer incidence has increased significantly from 0.60 to 1.45 per 100,000 in the 20 years (P < 0.001). This increase is mainly amongst men and age groups 40-59 years with a significant reduction in age at diagnosis by 2 years from 61.6 years in the first decade to 59.6 years in the second decade (P < 0.001). Survival was worse in men, older age groups and in the presence of synchronous tumours (P < 0.001). There has been a statistically significant increase in median survival times from tonsil cancer by about 3 years from 2.7 years in the first decade to 5.7 years in the second decade of this study (P < 0.001).

CONCLUSIONS

Tonsil cancer incidence has increased in the 20 years of this study in South East England, especially amongst men and age groups 40-59 years. There has also been significant reduction in the mean age at diagnosis and an increase in median survival times for tonsil cancer. Further studies are needed to explain these trends.