Head and neck cancer (HNC) is a significant public health problem worldwide due to its high mortality and morbidity. Most head and neck cancers arise from the lining of the mouth and throat, and can be related to major risk factors including tobacco use, alcohol consumption and human papilloma virus. Other common chronic oral diseases are also known to increase the risk of developing HNC. These include oral lichen planus, oral submucous fibrosis, leukoplakia, and periodontal diseases. In the UK, little is known about the relationship between these diseases and HNC. Consequently, it is unclear whether individuals with HNC associated with these diseases could have more aggressive behaviour comparing to others without. Previous studies suggested that following their primary cancer; these patients were likely to develop more episodes of HNC and hence increase the rate of death.
We plan to use data from a large number of patients to assess the association between these common oral diseases and the development of HNC. The findings of the study will improve our knowledge about the behaviour of this cancer in these oral diseases as well as gathering information that could help doctors to improve their patients' management with/without risk of HNC.
We aim to assess the associations between oral lichen planus (OLP), oral submucous fibrosis (OSF), leukoplakia (LK) and periodontal diseases (PD), and the development of head and neck cancer (HNC) in a representative sample of the UK population using electronic health records from primary and secondary health care databases during 1997 to 2014. The hazard ratios (HR) of HNC among patients with/without the diseases of interest will be calculated using Cox proportional hazard models adjusted for potential confounding factors. We shall also consider the role of age, gender, medications, and other specific underlying diseases as effect modifiers.
With respect to the impact of these common oral disorders upon cancer prognosis, we plan to study survival rates by using Kaplan-Meier methods. Moreover, we will assess long-term cancer behaviour through the analysis of a number of additional prognostic markers/surrogates including (i) number of additional malignant events after the first diagnosis of HNC (new primary cancers), (ii) the total number of outpatient visits, (iii) the total number of inpatient admissions, (iv) the treatments received, and (v) the development of complications of anti-cancer therapy (fibrosis, dry mouth and jaw osteoradionecrosis).
PRIMARY OUTCOME
- The associations between the development of head & neck squamous cell carcinoma and oral diseases known to increase the risk of head & neck cancer (the diseases of interest) including: oral lichen planus, oral submucous fibrosis, leukoplakia, periodontal disease.
Outcome of interests will be:
- The incidence of head and neck squamous cell carcinoma
- Time to the first diagnosis of head and neck squamous cell carcinoma
- The associations with traditional risk factors for head & neck squamous cell carcinoma including smoking and alcohol.
SECONDARY OUTCOME
- The prognosis of head & neck cancer in patients with a history of the above cancer- predisposing oral diseases vs those without an history of these conditions, as expressed by:
1. Overall survival rates and disease-specific survival rates
2. Stage of first HNC
3. Stage of subsequent HNC
4. The number of additional head & neck cancer events following the first malignant episode
5. The treatment received (surgery, chemotherapy and/or radiotherapy)
6. The number of inpatient admissions
7. The number of outpatient appointments
8. The development of radiotherapy-induced jaw osteonecrosis
9. The development of radiotherapy-induced soft tissue fibrosis (trismus and dysphagia)
Stefano Fedele - Chief Investigator - University College London ( UCL )
Kununya Pimolbutr - Corresponding Applicant - Eastman Dental Institute
Arturo Gonzalez-Izquierdo - Collaborator - University College London ( UCL )
Spiros Denaxas - Collaborator - University College London ( UCL )
Stephen Porter - Collaborator - University College London ( UCL )
HES Admitted Patient Care;HES Outpatient;NCRAS Cancer Registration Data;ONS Death Registration Data;Practice Level Index of Multiple Deprivation