Oral squamous cell carcinomas and oral potentially malignant disorders: A Latin American study.

OBJECTIVE: To determine the frequency of oral squamous cell carcinoma (OSCC) associated or not with oral potentially malignant disorders (OPMD), and the epidemiological profile and traditional risk factors in Latin America. METHODS: A retrospective observational study was conducted in 17 Latin American centres. There were included cases of OSCC, analysing age, gender, OSCC and their association with previous OPMD. Clinicopathological variables were retrieved. The condition of sequential-OSCC versus OSCC-de novo (OSCC-dn) was analysed concerning the aforementioned variables. Quantitative variables were analysed using Student's t-test, and qualitative variables with chi-square. RESULTS: In total, 2705 OSCC were included with a mean age of 62.8 years old. 55.8% were men. 53.75% of the patients were smokers and 38% were common drinkers. The lateral tongue border was the most affected site (24.65%). There were regional variations in OPMD, being leukoplakia the most frequent. Of the overall 2705 OSCC cases, 81.4% corresponded to OSCC-dn, while s-OSCC were 18.6%. Regarding lip vermillion SCC, 35.7% corresponded to de novo lip SCC and 64.3% were associated with previous OPMD. CONCLUSIONS: In Latin America, OSCC-dn seems to be more frequent with regional variations of some clinical and histopathological features. Further prospective studies are needed to analyse this phenomenon.

Oral squamous cell carcinoma (OSCC) tumors from heavy alcohol consumers are associated with higher levels of TLR9 and a particular immunophenotype: Impact on patient survival.

Oral squamous cell carcinoma (OSCC) is one of the most frequent types of oral cancer in developing countries and its burden correlates with exposure to tobacco and excessive alcohol consumption. Toll like receptors (TLRs) are major sensors of inflammatory stimuli, from both microbial and sterile causes and as such, they have been related to tumor progression and metastasis. Here, we evaluated the expression of TLR2, 4 and 9 as well as CD3+, CD8+ and Granzyme B+ cell infiltration by immunohistochemistry in oral samples of 30 patients with OSCC, classified according to their consumption of alcohol. Our findings indicate that there is a significant association between heavy alcohol consumption and tumors with higher expression levels of TLR9. Moreover, patients with TLR9high tumors, as well as those who indicated high consumption of alcohol exhibited a diminished overall survival. TCGA data analysis indicated that TLR9high tumors express a significant increase in some genes related with the oral cavity itself, inflammation and tumor promotion. Our analysis of tumor infiltrating leukocytes demonstrated that the major differences perceived in heavy alcohol consumers was the location of CD8+ T cells infiltrating the tumor, which showed lower numbers intratumorally. Our data suggest the existence of a pathogenic loop that involves alcohol consumption, high TLR9 expression and the immunophenotype, which might have a profound impact on the progression of the disease.

Reexamination of delays in diagnosis of oral cancer following an intervention program in Cordoba, Argentina.

OBJECTIVE: We compare the results of delay in oral cancer diagnosis before and after a campaign directed toward dentists and raising awareness of the population to achieve early diagnosis of oral cancer in Córdoba, Argentina. The campaign included training dentists in diagnostic skills and a public awareness program through media and networks. STUDY DESIGN: Clinical records (period 1: before intervention program, n = 70; period 2: after intervention program, n = 60) of patients presenting with oral squamous cell carcinoma treated in 2 referral centers were analyzed. Records included first symptoms, first consultation with a health professional, and the time when treatment was formulated. RESULTS: Oral cancer diagnosis at early stages increased from 27% (period 1) to 40% (period 2). Biopsy at first consultation was indicated in 6% of patients in period 1 and in 23.3% in period 2 (odds ratio = 4.68; 95% confidence interval, 1.87-11.73; P < .05). Professional delay at early stage decreased from 72% in period 1 to 36.8% in period 2. During period 1, for initial stage cancer, the average patient and professional delays were 2.7 and 2.9 months, respectively (P = .06); in period 2, patient delay was 2.67 months and professional delay was 1.34 months (P = .005). CONCLUSION: The intervention program helped to improve early-stage diagnosis from 27% to 40% by reducing professional delays.