Immunohistochemical study of GLUT-1 in oral peripheral nerve sheath tumors.

AIM: To investigate the immunoexpression and diagnostic applicability of human erythrocyte-type glucose transporter protein (GLUT-1) in oral peripheral nerve sheath tumors. MATERIAL AND METHODS: Specimens diagnosed as oral peripheral nerve sheath tumors archived in the Oral Pathology Service of Universidade Federal de Minas Gerais from 1966 to 2006 were evaluated. Thirty-four lesions were included: 15 traumatic neuromas, 11 neurofibromas, four neurilemmomas, and four malignant peripheral nerve sheath tumors (MPNST). One case of neurofibroma was associated with neurofibromatosis type I. Immunohistochemistry for S-100 and GLUT-1 was performed. S-100 was immunopositive in all lesions. RESULTS: Benign lesions were immunopositive for GLUT-1 except in two (18.2%) cases of neurofibromas. In the traumatic neuroma, the perineuriums were immunopositive for GLUT-1. In the neurofibroma, the immunoreactivity was heterogeneous. Immunopositivity was observed at levels of 54.5% in the periphery of the lesion, 9.1% in the center, and 18.2% in both. The neurilemmoma demonstrated immunopositivity in the capsule. One case (25%) of MPNST presented GLUT-1 positive stain in occasional cells distributed homogeneously in all the tumor area. CONCLUSION: GLUT-1 is a useful marker for perineurial cells and should be included in the oral peripheral nerve sheath tumors immunophenotyping thus aiding in the correct diagnosis of these lesions.

GLUT-1 in oral benign vascular lesions.

AIM: To investigate the accuracy of histological diagnosis of oral hemangioma, oral vascular malformation and oral pyogenic granuloma according to immunohistochemical evaluation of the human erythrocyte-type glucose transporter protein (GLUT-1), and to observe the immunoexpression of this protein in oral varix. MATERIALS AND METHODS: Immunohistochemistry for GLUT-1 was performed in 93 histologically diagnosed cases of oral benign vascular lesions: 17 vascular malformations, 19 hemangiomas, nine varix, and 48 pyogenic granulomas. Descriptive analyses were performed. RESULTS: None of the cases of the oral benign vascular lesions evaluated were immunopositive to GLUT-1. The 19 cases histologically diagnosed as oral hemangioma that showed negative staining to GLUT-1 were reclassified as oral pyogenic granuloma or oral vascular malformations. The histological evaluation itself is not enough to obtain the correct diagnosis of oral HEM as none of the sample cases were true hemangioma. All sample cases with initial vascular malformation or pyogenic granulomas classification were negative to GLUT-1, demonstrating the accuracy of histological diagnosis of these lesions itself. Oral varix showed negative staining to GLUT-1 in blood vessels. CONCLUSIONS: GLUT-1 is an useful, effective and important auxiliary marker for the diagnosis of oral benign vascular lesions. CLINICAL RELEVANCE: This study showed that histological diagnosis alone is not sufficient to correct diagnoses of oral hemangioma. Moreover, immunohistochemistry to GLUT-1 is a useful and easy diagnostic method that may be used to avoid such misdiagnosis. Accurate diagnosis of these oral lesions has an important clinical relevance allowing: (1) correct management, (2) adequate communication among the multidisciplinary team (dentist, dermatologist, pediatrist, radiologist, pathologist, and surgeon), (3) understanding of the biological behavior of the lesions, and (4) facilitate the development of new therapeutic modalities. Thus, supporting the use of this marker in medical and dentistry communities is warranted.