Oral cancer: A multicenter study.

BACKGROUND: To determine the prevalence and clinicopathologic features of the oral cancer patients. MATERIAL AND METHODS: Biopsy records of the participating institutions were reviewed for oral cancer cases diagnosed from 2005 to 2014. Demographic data and site of the lesions were collected. Sites of the lesion were subdivided into lip, tongue, floor of the mouth, gingiva, alveolar mucosa, palate, buccal/labial mucosa, maxilla and mandible. Oral cancer was subdivided into 7 categories: epithelial tumors, salivary gland tumors, hematologic tumors, bone tumors, mesenchymal tumors, odontogenic tumors, and others. Data were analyzed by descriptive statistics using SPSS software version 17.0. RESULTS: Of the 474,851 accessioned cases, 6,151 cases (1.30%) were diagnosed in the category of oral cancer. The mean age of the patients was 58.37±15.77 years. A total of 4,238 cases (68.90%) were diagnosed in males, whereas 1911 cases (31.07%) were diagnosed in females. The male-to-female ratio was 2.22:1. The sites of predilection for oral cancer were tongue, labial/buccal mucosa, gingiva, palate, and alveolar mucosa, respectively. The three most common oral cancer in the descending order of frequency were squamous cell carcinoma, non-Hodgkin lymphoma and mucoepidermoid carcinoma. CONCLUSIONS: Although the prevalence of oral cancer is not high compared to other entities, oral cancer pose significant mortality and morbidity in the patients, especially when discovered late in the course of the disease. This study highlights some anatomical locations where oral cancers are frequently encountered. As a result, clinicians should pay attention to not only teeth, but oral mucosa especially in the high prevalence area as well since early detection of precancerous lesions or cancers in the early stage increase the chance of patient being cured and greatly reduce the mortality and morbidity. This study also shows some differences between pediatric and elderly oral cancer patients as well as between Asian and non-Asian oral cancer patients.

Correlation of collagenolytic enzymes and inhibitors in gingival crevicular fluid with clinical and microscopic changes in experimental periodontitis in the dog.

The quadrants of the jaw in 2 beagle dogs had various forms of periodontal disease induced by ligatures placed around second, third and fourth premolars in one quadrant and, 2.5 months later, around the same teeth in a second quadrant; gingivitis was allowed to develop in a third quadrant after 4 months; the fourth quadrant served as a healthy control. Crevicular fluid flow, plaque index, gingival index, attachment levels and recession were determined at intervals and collagenolytic activity measured in the fluid. The dogs were killed after 5 months and sections of each site prepared for histomorphometry. Clinically-inflamed and degenerating sites had significantly higher collagenolytic activities (p less than 0.001), lower collagenase inhibitor activities and greater fluid flow than control sites which showed abundant inhibitor activity and minimal active enzyme. Periodontitis sites had higher active enzyme, compared to latent enzyme activities, whereas latent collagenase was predominant in control and gingivitis sites. The collagenolytic activities in periodontitis sites fluctuated with time, suggesting a cyclical pattern. Active enzyme activities correlated strongly with gingival crevicular fluid flow and attachment loss. Periodontitis sites had much more inflammatory-cell infiltration than control and gingivitis sites (p less than 0.001). Thus periodontal disease may be monitored by examination of crevicular fluid collagenolytic enzymes, inhibitors and fluid flow, and these criteria may prove more meaningful than current clinical criteria.