Toluidine Blue Versus Frozen Sections for Assessment of Tumor Margins in Oral Squamous Cell Carcinoma

The incidence of oral cancer remains high, it is ranked to be the sixth most common cancer worldwide, oral squamous cell carcinoma represent more than 90% of all oral malignances. Standard treatment for oral squamous cell carcinoma is surgical resection with free margin. Negative margin status is an important for control local recurrence and improve outcome in squamous cell carcinoma of the head and neck. Hematoxylin and Eosin (H\&E) Frozen section biopsy is useful tool for intraoperative assessment of resected margins and control of local recurrence, allowing for additional resection intraoperatively in case of positive margins. However in the least developed countries with limited resource, the frozen section is not available in a majority of centers, in addition to that if present in developed countries, it somewhat considered time and cost consumer. Toluidine blue(TB) is metachromatic stain, easily available, economical, with high affinity for DNA and RNA. It is rapidly uptaken by malignant epithelium which contain quantitatively more nucleic acid than normal tissue. It has been widely used as screening tool for malignant and premalignant lesion. The purpose of this study is to test the accuracy of toluidine blue in the assessment of intraoperative tumor margin after excision of oral squamous cell carcinoma(OSCC)in comparison to H\&E stain on frozen section.