Assessment of tumour invasion into the mandible: the value of different imaging techniques

• Published in: European radiology 1998-01, Vol.8 (9), p.1552-1557
• Main Authors: van den Brekel, M W, Runne, R W, Smeele, L E, Tiwari, R M, Snow, G B, Castelijns, J A
• Format: Article
• Language: English
• Subjects: Adult; Aged; Carcinoma, Squamous Cell - diagnosis; Carcinoma, Squamous Cell - diagnostic imaging; Carcinoma, Squamous Cell - pathology; Carcinoma, Squamous Cell - surgery; Diagnostic Imaging; False Positive Reactions; Female; Humans; Magnetic Resonance Imaging; Male; Mandibular Neoplasms - diagnosis; Mandibular Neoplasms - diagnostic imaging; Mandibular Neoplasms - pathology; Mandibular Neoplasms - surgery; Medical imaging; Middle Aged; Mouth Floor - pathology; Mouth Neoplasms - pathology; Neoplasm Invasiveness; Osteotomy - methods; Predictive Value of Tests; Radiography, Panoramic; Retrospective Studies; Sensitivity and Specificity; Tomography, X-Ray Computed
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s003300050585

In oral carcinomas close to the mandible, tumour invasion of the mandible is important in selecting segmental or marginal resection. Imaging may play a role in assessing tumour invasion. This study compares the accuracy of panoramic X-ray, CT and MR imaging in assessing invasion of the mandible in 29 patients. At histopathology, 6 patients had mandible erosion, 12 had invasion and 11 had an intact mandible. Magnetic resonance imaging had the highest sensitivity (94%), but a low specificity (73%), with 3 of 11 intact mandibles interpreted as positive. Furthermore, MR often overestimated the extent of tumour invasion. On the other hand, CT and panoramic X-ray had a lower sensitivity (64 and 63%, respectively) and a higher specificity (89 and 90%, respectively). Computed tomography (using 5-mm sections) and panoramic X-ray had a similar accuracy, and negative findings do not exclude invasion. Magnetic resonance imaging was the most sensitive technique but had more false positives and frequently overestimated the extent of tumour invasion. Because none of the radiological techniques are accurate enough, clinical examination seems at present to remain the most important modality in deciding between segmental and marginal resection. Tumour invasion at CT or panoramic X-ray is a strong argument for a segmental resection.