Computed Tomographic Qualitative Diagnosis of Renal Masses

Abstract

Objective: To analyze the CT findings of renal masses and to investigate the value of CT imaging in qualitative diagnosis of these diseases. Methods: Twenty-eight cases of renal masses, proven surgically and pathologically, were retrospectively analyzed. Pre-and post-contrast CT scans were performed in all cases. Results: Twenty-one of 28 cases (75%) were diagnosed as having malignant tumors with 16 cases of renal cell carcinoma (RCC) showing as irregular-shaped low density soft tissue mass with no or slight enhancement. Ten of 21 cases were diagnosed as having carcinoma of the renal pelvis showing as soft tissue mass in renal pelvis with no or slight enhancement. Three of 21 cases were diagnosed as having nephroblastoma (Wilms' tumor) showing as larger irregular lobucated mass with no enhancement. Three of 28 cases (11%) of benign tumors were diagnosed as having angiomyolipoma (AML). Two cases showed a mixed density mass while another case showed iso-density mass. The soft tissue part of the tumor showed enhancement while the area of fat didn't show any enhancement of the contrast medium. Four of 28 (14%) included 3 cases of renal cysts showing as classic cystic lesions with clear-margin. No enhancement was found. In the remaining one case of renal abscess, CT showed a mixed density mass of soft tissue and cyst with slight enhancement of soft tissue part while no enhancement of cystic part. Conclusion: Pre-contrast and post-contrast CT scans in combination with history play an important role in the diagnosis of renal masses.Computed tomography (CT) is generally accepted as a critical imaging tool for the classification of renal masses. With the development of CT and MRI, there has been an increase in the detection of renal masses. In actual practice, it is still difficult in differentiating benign from malignant renal masses. Differentiation of various renal masses to determine which are benign and require no further study or treatment and which require surgical or other treatment is based on results of both clinical and imaging assessment. This report describes our 1-year experience using spiral CT in 28 patients with renal masses and investigates the value of CT imaging in differential diagnosis of these diseases. Materials and methodsTwenty-eight patients referred for renal masses that had been suspected or detected with spiral CT were enrolled. The study group consisted of 15 men and 13 women aged 2-73 years (mean, 52 years). The main symptoms include lumbar pain, painless hematuria, lower abdominal pain, frequent micturition and abdominal mass. Four cases with no symptom were detected by ultrasound (US) in routine health examinations.Pre-and post-contrast CT scans were performed in all patients (18 cases by GE prospeed CT scanner and 10 cases by Elscint Twin CT scanner). Oral contrast material was administered before scanning in all cases to fill the gastrointestinal tract. Preliminary scan without contrast material was obtained and then contrast material was powerfully injected intravenously at the rate of...