ACCURACY OF MRI IN MEASUREMENT OF DEPTH OF INVASION IN ORAL CANCER AND ITS HISTOPATHOLOGICAL CORRELATION

Abstract

AIM: To evaluate accuracy of MRI in measurement of Depth of Invasion and Bone involvement in Oral cancer and its histopathological correlation.

Material & methods: 70 patients with biopsy proven oral cancer with clinical stage at or below T4a were included in this hospital based descriptive type of observational study. All patients underwent preoperative MRI examination. MRI was performed on PHILIPS INGENIA 3 TESLA MRI. Images were interpreted for Depth of invasion and Bone involvement. All patients underwent surgery and the final diagnosis was made by histopathology. Statistical analysis was applied to find out the Sensitivity, Specificity, Accuracy, PPV and NPV of MRI. Correlation was inferred by Pearson’s Correlation coefficient. P-value < 0.05 was taken as significant.

Results: Average Depth of invasion calculated on MRI was 8.48mm and by histopathology was 6.90mm.Pearsons correlation coefficient was 0.988. Shrinkage factor was 0.81. Sensitivity, specificity, accuracy, PPV and NPV of MRI in predicting Bone invasion was 92.3%, 90.90%, 91.42%, 85.71% and 95.23% respectively.

 Conclusion: Depth of invasion in oral malignancies can be measured reliably on MRI which helps in predicting cervical lymph nodal metastasis which can be used as an important supportive tool in deciding type of neck dissection and prognosis of patient.

Keywords: Depth of invasion, MRI, Oral Cancer.