Oral Cancer Knowledge, Attitudes and Practices among Primary Oral Health Care Dentists in Kuwait

Background: Oral cancer signifies a public health concern of international importance. Early detection of oral cancer can improve the prognosis and the 5-year survival rate. Objective: The aim of this study was to assess the level of oral cancer knowledge, opinion, attitudes and practices among dentists working at the primary oral health care centers in Kuwait. Methods: In this cross-sectional study, self-reported questionnaire was distributed to the dentists working at the primary oral health care centers in Kuwait. A total of 289 dentists participated in the present study. The questionnaire included 23- questions on oral cancer knowledge, opinion, attitudes and practices. Results: The mean age of the dentists was 35.2 ± 10.9 years. Approximately, all dentists (99.7%) were aware of the major risk factors that were most likely associated with oral cancer. Overall, majority of the participants knew the most common form of oral cancer (80.6%), most common site (80.3%) and the likely lesions associated with oral cancer occurrence (87.9%). A large number of dental practitioners (81%) would routinely refer a patient with a suspicious lesion to a specialist. Nearly one-third (32%) reviewed their patients’ oral cancer risk factors. Approximately two-thirds (62%) assessed the use of tobacco in their practice. Almost, all (92.4%) were interested in attending continuing education courses on oral cancer. Conclusions: Majority of the participants presented good knowledge about various aspects of oral cancer. More continuing education programs on risk factors and diagnosis of oral cancer should be organized to train the dentists. Oral cancer screening should be a routine procedure for the high risk patients at the primary oral health care centers in Kuwait.


Introduction
which also considered oral cancer prevention, emphasized that the involvement of oral health professionals in early detection, diagnosis and treatment as an integral part of national cancer control programmes (Petersen, 2008).
In Kuwait, head and neck cancers are common sites of occurrence, the most predominant site being the nasopharynx (Morris et al., 2000). In an earlier study, Morris et al., (2000) conducted a computer search at the Kuwait cancer registry, for all cancers of the lip, oral cavity, and pharynx in the 10 years, from 1979 to 1988. They recorded 784 cases (7.4%) during this period out of a total of 10,539 cancers; the most frequent sites of cancer were the nasopharynx (25%), salivary glands (24%), and hypopharynx (14%). In 2008, the oral cancer incidence rate in Kuwait was 1.4 (per 100,000) and the mortality rate 0.6. The incidence rate in women was higher (1.8 per 100,000) than in men (1.1) (Ferlay et al., 2008). The male: female ratio for both incidence and mortality rates in 2012 were 1.5:1.3 and 0.3:0.7 respectively (Ferlay et al., 2012). Although the mortality rate is not very high in Kuwait, early detection of oral cancer is needed because of the increased consumption of tobacco in the last few years among Kuwaiti population (Memon et al., 2000).
Early detection of oral cancer can improve the prognosis and the 5-year survival rate Messadi et al., 2009). Although most of the dentists mentioned that they perform an oral examination on their patients, many studies indicate that dentists' lack knowledge of the etiology and diagnosis of oral cancer (Alfano and Horowitz, 2001). A previous study found that there is a delay in the early detection of oral cancer by the dental professionals (McLeod et al., 2005).
Several studies have assessed the dentists' knowledge, attitudes, and opinions regarding oral cancer and the early detection of oral cancer Patton et al., 2005;Gajendra et al., 2006;Ariyawardana and Ekanayake, 2008;Applebaum et al., 2009;Joseph et al., 2012;Alaizari and Al-Maweri, 2014;Saleh et al., 2014;Sarabadani et al., 2016;Mariño et al., 2017;Hashim et al., 2018;Jboor et al., 2019;Khattab et al., 2019). These studies showed the necessity to enhance the knowledge on preventing and early detection of oral cancer. A previous study done in Kuwait among dentists working at the Ministry of Health dental centers and the University dental center assessed their oral cancer awareness (Joseph et al., 2012). Another study, which assessed the oral cancer knowledge among undergraduate dental students in Kuwait University, emphasized the necessity for a structured teaching program with importance on early detection and risk factors of oral cancer (Joseph et al., 2015).
The primary oral health care centers provide dental services in all the six governorates in the State of Kuwait and the dentists working in the primary oral health care centers provide the oral health care for patients. Since there is a lack of baseline information about the oral cancer knowledge levels among the dentists working at the primary oral health care centers in Kuwait, it is important to evaluate their knowledge and practices. The present study was conducted to assess the level of oral cancer knowledge, opinions, attitudes, and practices among dentists working at the primary oral health care centers in Kuwait.

Study design
This is a cross-sectional study among the dentists practicing at the primary oral health care centers in Kuwait. This study was conducted under the supervision of Kuwait School Oral Health Program in collaboration with the Dental Administration, Ministry of Health, Kuwait. The study protocol was approved by the Dental Administration, Ministry of Health Ethical Committee and the School Oral Health Program Research Committee.

Study setting and participants
Only dentists working at the primary oral health care centers were included in this study. Six dental assistants distributed the questionnaires; one at each governorate. All the dentists reached were invited to participate in the study. Altogether 410 dentists received the questionnaire.
A covering letter explaining the purpose of the study was included.

Study questionnaire
A 23-item questionnaire in English was developed and utilized in this study, which included previously validated questions (Patton et al., 2005;Gajendra et al., 2006), and also questions designed for this study. The questionnaire was pretested in a pilot study among 40 dentists who attended the previous annual meeting of Kuwait division of the IADR (KuADR). The first section of the questionnaire included 6 questions regarding dentists' demographic characteristics. The demographic data collected were age, gender, date of graduation, the level of education, nationality, and the working site. The second section included 17 questions about the dentists' oral cancer knowledge, attitude, opinions, and practices. Nine knowledge questions were about the oral cancer risk factors, most common forms of oral cancer, common age of diagnosis, most common sites of oral cancer, symptoms of both early, late stage of oral cancer, and the features of oral cancer metastases. Three questions were about the dentists' opinion on oral cancer training, overall dentists' current knowledge, and mandatory oral cancer screening. One attitude question was regarding attending oral cancer continuing education courses. Four questions were about their current practices including evaluating oral cancer risk factors and managing patients with suspicious lesions.

Statistical analysis
Data were managed and analyzed using Epi-Info 3.5.3 and SPSS 21.0 software (IBM Corp., Armonk, N.Y., USA). Frequencies and means (SD) were used for data description. Shapiro-Wilks test tested continuous variables for normal distribution. As data were normally distributed, t-test and ANOVA were used to examine the difference in mean knowledge, attitude, and practice scores according to gender, nationality, governorate, and level of education. Pearson correlation coefficient was used to evaluate the correlation between the scores and participants' age and years of experience. The significance level used was p < 0.05.

Results
From a total of 410 questionnaires distributed to the dentists, 289 were completed, resulting in a response rate of 71%. Of the 289 dentists who participated, 177 (61%) were Kuwaiti, 112 (39%) from other nationalities. The mean age was 35.2 ± 10.9 years with the gender distribution of 62.3% males and 37.7% females. Seventy-five percent of the dentists had only a bachelor degree, while the remaining quarter had a master degree, MEGD or PhD. Their mean years of experience was 11.7 ± 11.3 years. Table 1 summarizes the demographic characteristics of the participants. About 98.9% of the questions were answered.
The mean (SD; range) knowledge score was 6.58 (1.55; 3-9). Majority of the dentists (73.4%) answered the knowledge questions correctly. Approximately, all dentists (99.7%) were knowledgeable about tobacco use one-third (31.3%) of dentists were aware of the symptoms of the early stage of oral cancer. More than one-third (37.3%) of dentists knew the most common age of oral cancer diagnosis. The majority of dentists knew the most common form of oral cancer (80.6%), the most common site of oral cancer (80.3%) and the most likely lesions associated with oral cancer (87.9%). Descriptive analysis of knowledge responses is summarized in Table 2.
Kuwaiti dentists had significantly better mean knowledge scores compared to dentists with other nationalities (6.87 vs. 6.19, p < 0.001). There was no significant difference in knowledge between male and female dentists (p = 0.07), between dentists from different governorates (p = 0.06), or between dentists with different level of education (p = 0.61). Knowledge scores were significantly correlated with age and years of experiences (r = 0.271, p < 0.001; r = 0.302, p < 0.001, respectively).
Overall, more than half (58.5%) of the dentists answered opinion questions positively with a mean opinion score of 1.74 (0.2; 0-3). About 38% thought they had adequate training to perform oral cancer screening and only half (55%) of them thought that their oral cancer knowledge is current. Most of the dentists (82.4%) thought that oral cancer screening should be a mandatory procedure at the primary oral health care centers. There was no significant difference in opinion scores based on age, gender, nationality, governorate, the level of education, or years of experience. Opinion responses are summarized in Table 3. The majority of dentists (92.4%) and alcohol consumption as the two major oral cancer risk factors. About 83.7% of the dentists reported the symptoms of late stage of oral cancer correctly, and only Years of experience (mean ± SD) 11.6 ± 11.3    Table 4. Descriptive Analyses of Dentists' Practice were interested in attending continuing education courses on oral cancer with a mean score of 0.92 (0.27; 0-1).
There was no significant difference in attitude scores based on age, gender, nationality, governorate, the level of education, or years of experience. The mean practice score was 10.36 (2.19; 5-16). Overall, half (48%) of dentists always/usually follow the ideal practice regarding screening and managing oral cancer. Approximately, half of the dentists (56%) would always and a quarter (25%) of them usually refer a patient with a suspicious lesion to a specialist. Nearly one-third of the dentists (32%) reviewed their patients' oral cancer risk factors. Overall, two-third of the dentists (62%) reported that they assessed the use of tobacco in their practice. Majority of the dentists working at the primary oral health care centers did not ask their patients about alcohol consumption. There was no significant difference in opinion scores based on age, gender, nationality, governorate, the level of education, or years of experience. Distribution of different practice responses is summarized in Table 4.

Discussion
Since oral cancer is a disease that it is hard to diagnose in its early stage, dental health care professionals should have a significant role and responsibility in prevention and early detection of oral cancer. Understanding the knowledge, attitudes, and practices among dental practitioners is vital to assess their effectiveness in early detection and to reduce the mortality and morbidity of oral cancer . This study was done to assess the oral cancer knowledge, opinions, attitudes and practices among dentists working at the primary oral health care centers in Kuwait. This study's results are comparable to other studies done among similar participants Patton et al., 2005;Gajendra et al., 2006;Applebaum et al., 2009;Joseph et al., 2012;Alaizari and Al-Maweri, 2014;Saleh et al., 2014;Hashim et al., 2018;Jboor et al., 2019;Khattab et al., 2019).
Of 410 questionnaires distributed, 289 dentists returned completed questionnaires with a total response rate of 71% in this study. This response was higher than in similar studies which had only 9.4% (Mariño et al., 2017), 27.6% (Alaizari and Al-Maweri, 2014), 38% (Ariyawardana and Ekanayake, 2008), 41.7% (Saleh et al., 2014) and response rates from 50-59% Yellowitz et al., 2000;Patton et al., 2005;Gajendra et al., 2006;Applebaum et al., 2009). The reply percentage was similar to a previous study in Kuwait (76.5%) (Joseph et al., 2012). Less than one-third of dentists did not participate in this study. The possible reason could be that some of the dentists were not confident about their oral cancer knowledge. Another reason could be that some of the dentists graduated from dental schools with Arabic curriculum did not participate as the questionnaire was in English.
Tobacco and alcohol are the most important risk factors for oral cancer (Moreno-Lopez et al., 2000;Rodriguez et al., 2004;Petersen, 2009). In this study, almost all dentists identified tobacco use and alcohol consumption as the two major risk factors for oral cancer occurrence. This was consistent with recent studies; in which majority of dentists recorded similar oral cancer risk factors (Jboor et al., 2019;Khattab et al., 2019). As shown in prior studies, although a large percentage of dental practitioners identified tobacco and alcohol as major risk factors, few of them assessed their patients for alcohol use Gajendra et al., 2006).
In the current study, majority of the dentists had a good knowledge on the clinical presentation and risk factors of oral cancer. However, this knowledge could have had higher impact on the dentists' practice. Several studies that had been reviewed showed that dentists were knowledgeable about oral cancer risk factors, signs, and symptoms (Applebaum et al., 2009;Yellowitz et al., 2000;Gajendra et al., 2006;Hashim et al., 2018;Jboor et al., 2019). Also, an earlier study among undergraduate dental students in Kuwait University showed that their knowledge of non-risk factors was lesser than their knowledge of recognized risk factors (Joseph et al., 2015).
In our study, greater number of dental practitioners knew the most common site affected by oral cancer when compared to other studies (Applebaum et al., 2009;Yellowitz et al., 2000;Hashim et al 2018;Jboor et al., 2019). Similar to this study, majority of the dental students identified the most likely sites of oral cancer (Al-Maweri et al., 2015). Compared to this study, higher percentage of dentists in other studies thought that they were adequately trained to perform oral cancer screening (Applebaum et al., 2009;Jboor et al., 2019). Similar percentage of dentists believed that their knowledge regarding oral cancer was current as in our study (Applebaum et al., 2009), however some studies found higher percentage of dentists who perceived that their oral cancer knowledge was up-to-date Jboor et al., 2019). In our study, half of the primary oral health care dentists routinely followed the practice regarding screening and managing oral cancer; similar to a recent study in Australia; wherein half of the oral health professionals performed oral cancer screening (Mariño et al,. 2017). In other studies, more than half of the dentists thought that they had learnt the important skills for oral cancer screening (Sarabadani et al., 2016); whereas majority of dentists agreed that they were adequately trained in oral cancer screening (Ariyawardana and Ekanayake, 2008).
An earlier study in Kuwait (Joseph et al., 2012) demonstrated better knowledge of dentists about the symptoms of early oral cancer; wherein majority knew that the early oral cancer is asymptomatic compared to this study. This dissimilarity could be due to the differences between the dentists' affiliations. Majority of dentists routinely referred their patients with suspicious lesions to a specialist in this study which is similar to a previous study in Kuwait (Joseph et al., 2012) and higher than in an earlier study in the US (Patton et al., 2005).
A possible strength in this study was in the sample that only the dentists working at the primary oral health care centers were included. These dentists provide the primary oral health care to their patients in their practice and a good response rate was achieved. Another strength of this study was that the questions included in this study were pretested among the dentists who attended the previous KuADR conference in Kuwait. A likely limitation of this study was that dentists practicing in the private clinics were not included.
Delays in the diagnosis and referral of patients with oral cancer have not improved in spite of efforts to increase the awareness of the disease (McLeod et al., 2005). Continuing education courses can have a positive influence on dentists' knowledge and practices (Silverman and Rankin, 2010). Since primary oral health care dentists have a vital role in screening patients for oral cancer, education in oral cancer examination must be a regular part of continuing dental education courses. In this study, almost all dentists were interested in attending continuing education courses regarding oral cancer which is similar to other studies (Applebaum et al., 2009;Hassona et al., 2015;Khattab et al., 2019) and higher than in a previous study that was done in the US, wherein only 50% of the dentists indicated an interest in further training . Since most of the dentists in this study expressed their interest to attend continuing education training on oral cancer, this might be considered as a strong indicator for improving; as such courses enhance the prevention and early detection of oral cancer. In a recent study, the significance of enhanced educational methods for dentists on oral cancer detection and prevention was emphasized (Kebabcıoğlu and Pekiner, 2018).
Since oral cancer is generally linked to lifestyle and as primary oral health care providers; dentists should be aware of the risk factors and have a significant part in imparting knowledge about the benefits from the altering of lifestyle habits (Galvão-Moreira and da Cruz, 2017). Dentists working at the primary oral health care centers play an important role in the early detection of oral cancer and all patients should receive an oral cancer examination which takes only about 90 seconds as a part of a comprehensive oral examination (Horowitz, 2001). One important part of the primary oral health care is the early detection of oral cancer through the visual examination that can be done by the general practitioner dentists with minimal tools. Since, the visual examination of any oral epithelial changes is the gold standard of early detection of oral cancer (Epstein and Lonky, 2008); this examination should be a routine procedure at the primary oral health care centers in Kuwait.
In conclusions majority of the dentists presented good knowledge about various aspects of oral cancer. More continuing education programs on risk factors and diagnosis of oral cancer should be organized to train dentists. Oral cancer screening should be a routine procedure for the high risk patients at the primary oral health care centers in Kuwait.
This study was not funded. There is no conflict of interest regarding the study. Ethical approval for this study was obtained from the Ethical Committee, Dental Administration, Ministry of Health and the School Oral Health Program, Research Committee, Kuwait.