Factors related to diagnostic delay of oral squamous cell carcinoma in southern Thailand: Revisited.

OBJECTIVES: To evaluate the impact of more open access to health services by Thailand's universal health coverage (UHC) on diagnostic delay of oral squamous cell carcinomas (OSCC) by comparing results with our previous study prior to the UHC. Reasons for delay in attending healthcare professional (HCP) consultation were also investigated. METHODS: A structure questionnaire was employed to interview 154 OSCC consecutive patients. Variables were included for Cox proportional regression models to conclude the hazard ratio of each delay. RESULTS: Regarding patient delay, those who had more than 12-year education showed less delay (HR 0.46, 95% CI: 0.21-1.01) while longer delay was found in farmers (HR 1.49, 95% CI: 1.05-2.11). Compared with the previous study, there was no association between herbal medication and patient delay, herbal medication and total delay, nor religion and total delay. Professional delay showed no association with any variable. Only half of the patients received initial proper HCP management in both studies. Patient delay was mostly (89.9%) due to unawareness of the lesion severity. CONCLUSIONS: Open access to the healthcare system had an influence on diagnostic delay. Public education and precise clinical acumen by HCPs in OSCC diagnosis are needed for early detection.

Oral manifestations of HIV infection in relation to clinical and CD4 immunological status in northern and southern Thai patients.

OBJECTIVES: To assess prevalence and variations in the oral manifestations of HIV in HIV-infected subjects in southern Thailand (a new HIV epidemic) and northern Thailand (a mature epidemic), and the association with age, sex, risk behaviours, CD4 count and medication used. SUBJECTS AND METHODS: A total of 102 and 135 HIV-infected individuals were enrolled in northern and southern hospitals, respectively. Oral and haematological examination was performed after sociodemographic interview of the patients. Clinical history was retrieved from patients' medical records. RESULTS: Oral candidiasis (OC, 55%), oral hairy leucoplakia (OHL, 21%) and HIV-associated-periodontal disease (14%) were among the most common oral lesions in southern Thailand. OHL (38%), OC (25%), HIV-associated-periodontal disease (15%) were the three most common lesions in the north. A significant association was found between any oral lesion, OC, particularly the pseudomembranous type (PC), and CD4 < 200 cells mm(-3) at both sites. A negative relationship was found between systemic antifungal treatment and OC including PC and erythematous candidiasis (EC) in the southern data. OHL showed a positive relationship with male sex and a negative relationship with antiretroviral treatment in the northern site. Younger age and being a current smoker were positively associated with oral lesions in the southern group. CONCLUSION: OC, particularly PC, could be useful as a marker for immunosuppression, particularly where CD4 count cannot be determined routinely. Antifungal treatment is of benefit in the subjects who cannot afford highly active antiretroviral therapy (HAART).

Expression of p53 in oral squamous cell carcinoma and its association with risk habits in southern Thailand.

Tobacco smoking and alcohol drinking are the principal factors associated with p53 expression in oral squamous cell carcinomas (OSCC) in the west, whereas betel quid chewing and smokeless tobacco are important factors in the east. Variable results of p53 expression have been reported and it has been proposed that ethnic difference and a variation in the indigenous oral habit may be responsible for the finding. This study, therefore, investigated p53 expression among 106 OSCC patients from a southern Thailand population in which all four risk behaviours, tobacco smoking, alcohol drinking, betel quid chewing and use of smokeless tobacco, are practised. The associations of p53 expression with lifetime exposure to each risk behaviour were explored. Multivariate modelling showed that lifetime exposure to alcohol drinking was significantly positively associated with p53 expression (likelihood ratio P value 0.01). Betel quid chewing and tobacco smoking habit showed a trend of decreasing risk of p53 expression with increased lifetime exposure (OR 0.62, 95% CI 0.39-1.00 and OR 0.50, 95% CI 0.26-0.98, respectively). No significant association was found between p53 expression and clinico-pathological parameters. Further investigations are needed to study (1) the molecular alteration of p53 in each risk habit and (2) other possible pathways of oral carcinogenesis in betel quid- and tobacco smoking-associated OSCC in these group of patients.

Factors related to advanced stage oral squamous cell carcinoma in southern Thailand.

A critical factor that indicates a poor prognosis of oral squamous cell carcinoma (OSCC) is advanced stage disease. This study, therefore, aimed to identify the factors related to advanced stage (TNM staging III, IV) OSCC in Thailand. There were 161 patients with squamous cell carcinoma of the oral cavity and lip (ICD-9 140, 141, 143-5), included in the study. Sixty-two per cent of the patients presented with advanced stage disease. Information on demographic characteristics, risk habits, health-seeking behaviour prior to health care professional (HCP) consultation, tumour characteristics and patient and professional delay was obtained by questionnaire-based interview of the patients. These variables were included as initial variables in a logistic regression to calculate the odds ratio (OR) of advanced versus early stage OSCC. Having traditional herbal medication before HCP consultation significantly increased the risk of advanced stage OSCC (OR 5.77; 95% C.I. 1.25-26.62). Floor of mouth location of tumour was associated with a lower risk of advanced stage disease (OR 0.27; 95% C.I. 0.09-0.82) as was having an ulcer (OR 0.43, 95% C.I. 0.02-0.89). The findings indicate that having traditional herbal medication before HCP consultation increased the risk of advanced stage disease. The lower risk of advanced stage OSCC associated with ulcerative tumours and those on the floor of the mouth may be due to their being more readily detected by the patients.

Factors related to delay in diagnosis of oral squamous cell carcinoma in southern Thailand.

The factors related to patient, professional and total delay in 161 oral squamous cell carcinoma (OSCC) patients attending for treatment at a university hospital in southern Thailand were investigated. About 42 and 20% of these patients had a patient delay of more than 1 month and 3 months, respectively. About half of the patients received proper management from health care professionals (HCPs) on their first consultation. Traditional herbal medication use was significantly associated with prolonged patient delay (hazard ratio [HR] 0.46, 95% C.I. 0.28-0.76). None of the variables investigated had a significant association with professional delay. Traditional herbal medication use also significantly prolonged total delay (HR 0.45, 95% C.I. 0.27-0.74). Buddhists had shorter total delay than Muslims (HR 0.68, 95% C.I. 0.49-0.95). The present study indicates that both patients and HCPs are responsible for the diagnostic delay. A health education campaign about OSCC and the use of traditional herbal medication is recommended to shorten patient delay. Continuing education on oral cancer and precancer for HCPs and clarification of the referral system are needed to effect a major reduction in professional delay.

p53 expression in oral precancer and cancer.

Expression of the p53 tumour suppressor gene is a frequent finding in human malignancies, including oral cancer, and it has been detected in some potentially malignant lesions. The results of the present project showed that 35 of the 41 (85 per cent) oral mucosal lesions with histological evidence of epithelial dysplasia expressed p53, but the presence or absence of p53 staining could not be used to predict the outcome of potentially malignant oral mucosal lesions.

A clinical study of oral tori in southern Thailand: prevalence and the relation to parafunctional activity.

The objective of the present study was to investigate the relationship of oral tori and occlusal stress as indicated by parafunctional activity (clenching and grinding) and to report the prevalence of torus palatinus (TP) and torus mandibularis (TM) among patients attending a dental school hospital in southern Thailand. Six-hundred-nine individuals, 183 males and 426 females, were interviewed and examined for the presence of clenching and grinding habit. The presence of TP and TM was also examined in each individual and in the case of TM size was recorded. Tabulated analysis was carried out to find the crude relationships of the parafunction, age and sex to the presence of TP or TM. The relationships were then analyzed by logistic regression. Of these individuals, 376 (61.7%) had TP, whereas 182 (29.9%) had TM. The male:female prevalence ratios of TP and TM were 1:1.4 and 1:0.94, respectively. TP was, thus, more frequent in females. A strong association between clenching and grinding and the presence of TM was found. The presence of TM might be useful as a cue to look for signs of parafunction.

Relationship between oral tori and temporomandibular disorders.

The aim of the study was to compare the presence of oral tori and parafunctional activity (clenching, grinding teeth and/or bruxism) between temporomandibular disorder (TMD) patients and control subjects. Fifty-nine TMD and 353 control subjects were included. The groups were similar in sex and age distribution. There was no significant difference in prevalence of torus palatinus (TP) between TMD and control group (P = 0.2), while torus mandibularis (TM) was more common in TMD than in control group (P < 0.0005). Parafunctional habit was more common in TMD patients than in the control group (P < 0.0005). There was no significant association between size of TM and Helkimo's dysfunction index (P = 0.4). The results show that the prevalence of TM and parafunctional activity was higher in TMD than control patients. TM might be useful as an indicator of increased risk of TMD in some patients.

Expression of p53 in oral mucosal hyperplasia, dysplasia and squamous cell carcinoma.

OBJECTIVE: To assess p53 expression in a range of oral mucosal lesions and to relate the results to the clinical outcome in patients with dysplastic oral mucosal lesions and oral squamous cell carcinomas (OSCC). MATERIALS AND METHODS: Archival tissue was available for eight cases of normal oral mucosa, 50 cases of oral mucosal hyperplasia, 41 cases of oral mucosal dysplasia and 48 cases of OSCC. The monoclonal antibody DO-7, reactive to p53 protein, was applied to paraffin-embedded sections using microwave pretreatment and immunohistochemical techniques. RESULTS: The results showed that normal oral mucosa did not express p53. Positive nuclear staining was found in 18/50 (36%) cases of hyperplasia, 35/41 (85%) cases of dysplasia and 45/48 (94%) cases of OSCC. None of the p53 negative dysplasias progressed, while 19% of p53 positive cases of dysplasia recurred following excision and 11% of the cases underwent neoplastic transformation. Five out of 10 (50%) cases of severe dysplasia which were p53 positive resolved. CONCLUSION: The proportion of cases with positive p53 expression increased from hyperplasia to dysplasia to OSCC. These results may indicate an involvement of p53 in neoplastic transformation as well as in proliferative events although the presence or absence of p53 staining could not be used to predict the outcome of potentially malignant oral mucosal lesions.