Differential diagnosis of myoxid lesions in head and neck area with special staining of mucin

Myxoid histological pattern is of nonspecific features that is seen in most of benign and malignant lesions occupying a great mass of them. Thus, histopathologic diagnosis depends on a careful and precise investigation. The aim of this study was to differentiate between mucins in myxoid tissues through histochemical staining. Archives of three important educational pathology departments (Facutty of Dentistry of Tehran University, cancer institute of Imam Khomeini hospital and Amir alam hospital) were investigated and information on head and neck tumors with myxoid histopathologic pattern were worked out, then slides and paraffin embeded blocks were studied. Tissue slides of 5mm thickness were stained with PAS/Alcian blue technique and studied under light microscope. The notable standard was the predominant stain of mucin in histological field. The study of 41histologic slides countaining: malignant fibrous histocytoma (MFH)(n=4), Rhabdomyosarwma (n=6),Chondrosar coma (n=6), Schwannoma (n=7), Neurofibroma (n= 8), Pleomorphic adenoma (n=4) and Odontogenic myxoma (n=6), revealed that neurologic derived lesions and Rhabdomyo sarcoma and MFH had notable red field (neutral mucin nature) where as chondrosarcoma, pleomorphic adenoma and odontogenic myxoma had notable blue field (acidic mucin nature). Despite limited cases, the results showed that different nature of mucins in different lesions can be considered as a good criteria for differential diagnosis, however, more detailed studies are recommended.