Oral cancers are among the most prevalent malignancies in males. In developing countries like India where chewing tobacco and other carcinogen containing mixtures is common, incidence of oral cancers is high. Photodynamic therapy is emerging as a promising method for non-disfiguring treatment for early malignant lesions of the buccal mucosa with relatively few effects and potential for implementation in settings with limited medical infrastructure
We evaluate ultrasonography as an approach for assessment of PDT response in oral malignancies.In our study we selected stage 1 malignancy of the buccal mucosa using both ultrasonography followed by histopathology.The criterion for selection on USG was lesion length of 2cm or less and depth of 5mm confirmed by biopsy and histopathology analysis. Subsequently, the patients found positive on biopsy were treated with ALA PDT with a LED light source. Following treatment these patients were reassessed with ultrasound at day 10. The images obtained were compared and evaluated for change in the size of the lesion, their echopattern, vascularity, mucosal status etc.
It was found, lesions completely hypoechoic signifying necrosis came out negative on biopsy every single time, confirming hypoechogenecity as the single best indicator for success of PDT treatment. However, those lesions which did not develop necrosis but were negative on biopsy, the indirect markers were small initial size of the lesion, a lack of vascularity within the lesion and surrounding inflammation.
To conclude, ultrasonography is a convenient, reliable and radiation free method for post PDT evaluation of lesions of buccal mucosa.