Oral cavity, pharyngeal and salivary gland cancer: disparities in ethnicity-specific incidence among the London population.

OBJECTIVES

We examined the association between ethnicity and the incidence of oral and pharyngeal cancers in the London population.

METHODS

Data on London residents diagnosed with oral and pharyngeal cancer (ICD-10 codes C00-C14) between 1998 and 2007 were retrieved from the Thames Cancer Registry. Age-standardised incidence rate ratios (IRR) for cancers of the nasopharynx (C11), oropharynx (C09-C10), hypopharynx (C12-C13), oral cavity (C00.3-C06), salivary glands (C07-C08) and Waldeyer's ring (C02.4, C09, C11.1, C14.2) were calculated for different ethnic groups using White males and females as the baseline groups.

RESULTS

Records on 5833 individuals were examined, and ethnicity information was available for 4679 (80%) of these patients. The incidence rate of oral and pharyngeal cancer combined was 9.0 and 3.9 per 100,000 for males and females, respectively. Compared with their White counterparts, the highest incidence rate ratios of nasopharyngeal cancer were seen in Chinese males (IRR: 23, 95% confidence interval (CI): 7-73) and females (IRR: 16, 95% CI: 2-107). Waldeyer's ring cancers were most common in Bangladeshi and White groups. Analysis of the oropharynx and oral cavity cancers gave rise to variable but less obvious patterns among the different ethnic groups, whereas less variation was observed between ethnic groups for cancers of the hypopharynx and salivary glands.

CONCLUSION

The incidence rates of individual oral and pharyngeal cancer types are low, but seem to vary by ethnic group. The variation in incidence appears to be unique to the different cancer subtypes and may therefore reflect specific ethnicity-related risk factors.