Assessment of the accuracy of MRI in differentiating benign and malignant lesion by different intralesional tissue signal characteristics
Keywords:
MRI, Soft tissue tumors, malignant lesionsAbstract
Background:Despite the diversity associated with soft tissue tumour development, all diagnosis carry similar symptoms and treatment options. By systematically using clinical history, lesion localisation, mineralisation on radiographs and signal intensity characteristics on MR images, one can determine the diagnosis for the subset of determinate lesion that have characteristic clinical and imaging features and narrow the differential diagnosis for lesions that demonstrate indeterminate characteristics. Material & Methods:The present retrospective study was conducted at department of Department of Radiology at MRI Centre, M.B. Govt. Hospital, Udaipur. The study duration was September 2012 to March, 2015. The study group of 50 patients, consisted of mainly patients from different parts of Rajasthan and also some from the states like Gujarat and Madhya Pradesh. Results: In the present study, in demographic study youngest age was 6 months female with angiofibroma and oldest was 79 years male with Leiomyosarcoma. Most common age group over all was 31 to 40 years [24%]. Amongst malignant and benign most common age group was again 31- 40 years, 8% in benign and 16% in malignant. Benign lesions were more common in females and malignant were more common in males.Out of total study participants 50 patients, 32 cases were malignant and 18 cases were benign.Most tumors were hypointense on T1W study[58%] and hyperintense on T2W images[86%]. Heterogenous hyperintensity on T2W images was more common in malignant lesions than in benign. Sensitivity and specificity of this characteristic predicting malignancy is as follows. Statistics show that heterogenous hyperintensity has higher sensitivity, specificity, PPV and NPV in predicting malignancy and p value suggests that there is significant difference among the malignant and benign lesions. [Chi = 20.91; p = 0.0001].Conclusion:We concluded from the present study that MRI is the modality of choice for evaluation of soft tissue tumors along with highly sensitive in detection of soft tissue tumors almost 100%. MRI has an important role in determining the origin of these lesions and in defining their extent and relation to adjacent structures. However, it must be emphasized that MRI cannot completely distinguish benign from malignant lesions when radiologic evaluation is non-specific.