Methylene Blue Test in Assessing Disease Free Margins in Lingual Carcinoma Resection

Lingual squamous cell carcinoma is one of the most frequent localization of the oral carcinomas. The tongue neoplasia represents nearly 40% of the oral carcinomas. Recent studies showed an increasing trend of lingual carcinoma in young patients. Several staining tests have been described to early detect the disease. After detection, disease free margins resection will increase the survival rate. This study aims to analyze the methylene blue staining test in achieving disease free resection margins in lingual squamous cell carcinoma.

DNA Vaccine against Hamster Oral Papillomavirus-associated Oral Cancer

Previously we developed a carcinogenesis model involving the combination of 9, 10-dimethyl-1, 2-benzanthracene (DMBA) application with physical wounding of hamster lingual mucosa. The presence of a novel hamster oral papillomavirus (HOPV) was demonstrated and its genome sequenced. In the present study, this HOPV hamster model was used to test whether vaccination with the L1 gene could prevent the development of oral carcinoma. DNA plasmids encoding the L1 gene or the vector alone were injected intramuscularly into 20 vaccinated and 20 control hamsters, respectively. The lingual tips of the hamsters were painted with DMBA for 8 weeks. A portion of the lingual tips was excised, and the tips were then painted daily with DMBA until the animals were killed 13 days later. All control hamsters developed lingual carcinoma, whereas 12 of the L1-vaccinated hamsters showed no lesions. These results suggest that immunization with L1 DNA vaccines may prevent the development of papillomavirus-associated oral cancer.