Effectiveness of Computed Tomography Density Value in the Differential Diagnosis of Benign and Malignant Renal Lesions

Abstract

Purpose: We aimed to investigate the role of mean Hounsfield Unit(HU) values measured on enhanced or unenhanced Computed Tomography(CT) images for the differentiation of benign and malignant kidney lesions. Materials and Methods: In this retrospective study, CT images, demographic features, and histopathological results of the patients with renal lesions were reviewed from the hospital database. The pathological results were classified as benign and malignant. Mean attenuation values of the lesions were measured as HU on enhanced or un-enhanced CT images. The mean HU values of benign and malignant lesions were compared by using the student’s t-test. Results: The mean HU value of lesions who have enhanced CT scan with malignant histopathological results (17 males, 11 females) was 83,7±39,4, with benign histopathological results (5 males, 4 females) was 81,0±52,9. There was no statistically significant difference between malignant and benign lesions regarding the HU values on enhanced (70. Second delay) CT images (p:0.8704). The mean HU value of lesions which has unenhanced CT scan with malignant histopathological results (12 males, 9 females) was 29,3±8,1 with benign histopathological results (1 male, 4 females) was 9.4±42,0. The mean HU value of malignant lesions was higher than those of benign lesions on unenhanced images, and this difference was statistically significant (p:0,0426). Conclusion: The mean HU values of kidney masses on unenhanced CT images were found to be useful for the differentiation of benign and malignant lesions but values on enhanced (70 second delay) images in our study did not achieve such discrimination.

Keywords

• computed tomography
• hounsfield unit
• density
• imaging
• renal lesion