Investigations into oral health and dental care factors associated with oral cancer risk and management

Pye, Andrew David (2015) Investigations into oral health and dental care factors associated with oral cancer risk and management. MSc(R) thesis, University of Glasgow.

Abstract

Introduction:
In Scotland in 2010, 460 new cases of cancer of the oral cavity were reported with a crude rate of 8.8 per 100,000 person/year risk (ISD Scotland). Worldwide, oral cancer (also known as lip and oral cavity cancer) is the 15th most common cancer, with more than 300,000 new cases diagnosed in 2012 (2% of the total). Oral cancer is the 15th most common cancer in Europe, with around 61,400 new cases diagnosed in 2012 (2% of the total) (GLOBOCAN 2012). In order to reduce the incidence of oral cancer, risk factors need to be identified and appropriate preventative strategies developed.

In addition to significant mortality, there is significant morbidity associated with oral cancer. Patients can suffer from disfigurement, pain, reduced function and depressive illness as a result of the disease and its treatment. Guidelines state that oral cancer patients should receive pre- and post-operative dental assessments and management as part of their cancer treatment to reduce complications and improve outcomes (British Association of Head and Neck Oncologists, 2009, National Institute for Clinical Excellence, 2004, Scottish Intercollegiate Guidelines Network, 2006).

Aims:
To carry out a systematic review and meta-analysis of the world-wide literature regarding oral health and dental care factors associated with oral cancer risk.
To examine the level and degree of clinical dental care for patients diagnosed with and treated for head and neck/ oral cancer.
Materials and Methods:
A systematic review and meta-analysis of the world literature was undertaken assessing the association between oral health and dental care factors and the incidence risk of oral cancer. Studies were included if they reported odds ratios and corresponding 95% Confidence Intervals of oral cancer with respect to oral health or a dental care factor or if the estimates could be calculated or obtained. Meta-analyses were performed to quantify the risk associated with each factor. Included studies were assessed regarding heterogeneity and meta-analysis were carried out using a random effects model where heterogeneity was significant and a fixed effects model where heterogeneity was not significant. Included studies were also assessed regarding their methodological quality and sensitivity analyses and publication bias assessments were conducted.
Case records for head and neck cancer patients diagnosed 2002-2004 were examined and assessed for evidence of dental assessments in parallel to a large multi-centre case-control study. Data were compared to audit data collected from patients diagnosed with head and neck cancer 2013-2014.
Results:
The systematic search retrieved 8534 articles (after removal of duplicates, books and patents) which were screened against the inclusion criteria. This resulted in 18 studies that met the inclusion criteria. The overall estimate for general oral health associated with increased risk of oral cancer comparing the best oral health score with the worst was OR 3.91 (95% CI 2.29, 6.67) based on 3 studies. The overall estimate for gum bleeding associated with increased risk of oral cancer comparing the absence of gum bleeding with the worst score was 1.76 (95% CI 1.20, 2.58) based on 6 studies. The overall estimate for poor oral hygiene associated with increased risk of oral cancer was 3.56 (95% CI 2.52, 5.04) based on 2 studies. The overall estimate for 6 or more missing teeth associated with increased risk of oral cancer was OR 2.3 (95% CI 1.27, 4.18) based on 6 studies. The overall estimate for non-attendance at the dentist associated with increased risk of oral cancer was 1.45 (95% CI 1.12, 1.87) based on 3 studies. The overall estimate for denture-wearing associated with increased risk of oral cancer was 1.08 (95% CI 0.80, 1.46) based on 5 studies. The overall estimate for reduced frequency of toothbrushing associated with increased risk of oral cancer was reported as OR 1.75 (95% CI 1.21, 2.53) based on 6 studies.
Regarding dental assessment of head and neck cancer patients, 6 out of 43 (14%; 95% CI 4%, 24%) dentate patients from the 2002-2004 cohort had a pre-operative dental assessment compared to 45 out of 71 (63%; 95% CI 52%, 74%) of the dentate patients in the 2013-2014 cohort, which was a significant improvement. In the 2002-2004 cohort, 14 (18%; 95% CI 9%, 27%) patients out of 76 had a post-operative dental assessment compared to 19 (26%; 95% CI 16%, 36%) out of 74 patients were identified as having had some form of post-operative assessment or management, which was not a significant improvement (p= 0.28).
Conclusions:
The available evidence indicates that general oral health, gum bleeding, oral hygiene, missing teeth, dental attendance and frequency of toothbrushing are all risk factors for oral cancer. Denture use per se is not associated with an increased risk of oral cancer. Oral health factors and, more widely, dental care factors should be acknowledged alongside traditional smoking and alcohol behaviours as important risk factors for oral cancer.
An improvement in the frequency of pre-operative dental assessments has been seen. However, guidelines and standards that state that all oral cancer patients should receive a pre-operative dental assessment are not being met (British Association of Head and Neck Oncologists, 2009, National Institute for Clinical Excellence, 2004, Scottish Intercollegiate Guidelines Network, 2006) and we don’t appear to have achieved the quality performance indicator (Healthcare Improvement Scotland, 2014) stating that at least 90% of oral cancer patients should receive a pre-operative dental assessment. Post-operative dental assessments have not seen a significant improvement and compliance is difficult to assess against other research as there is little published work in this area. As standards have not been met, further efforts should be made to attempt to ensure dental assessment and management are integrated as part of the multidisciplinary team approach for patients with oral cancer.

• Item Type: Thesis (MSc(R))
• Qualification Level: Masters
• Keywords: Oral cancer, risk factors, oral health, dental care, dental assessment
• Subjects: R Medicine > RK Dentistry
• Colleges/Schools: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing > Dental School
• Supervisor's Name: Conway, Dr David, I and Cross, Dr Laura, J
• Date of Award: 2015
• Depositing User: Mr Andrew D Pye
• Unique ID: glathesis:2015-6483
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 19 Jun 2015 08:40
• Last Modified: 12 Aug 2015 08:31
• URI: https://theses.gla.ac.uk/id/eprint/6483