Malignant renal cysts: diagnostic performance and strong predictors at MDCT

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Multidetector-row CT (MDCT) is increasingly utilized for evaluating renal masses.
• Accurate differentiation between benign and malignant cysts is crucial for patient management.

Purpose of the Study:

• To evaluate the diagnostic accuracy of MDCT for malignant cystic renal masses.
• To assess interobserver agreement and the benefit of consensus reading.
• To identify strong predictors of malignancy in cystic renal masses.

Main Methods:

• Two radiologists independently assessed 125 cystic renal masses (72 benign, 53 malignant) using MDCT.
• Diagnostic accuracy, interobserver agreement (kappa statistic), and malignancy predictors were analyzed.
• Consensus reading was performed for cases with interobserver disagreement.

Main Results:

• High diagnostic accuracy was achieved (Az values 0.905-0.936), with sensitivity of 85-89% and specificity of 83-93%.
• Good interobserver agreement (kappa=0.696) was observed.
• Thickened irregular walls/septa and enhancing soft tissue components were significant predictors of malignancy.
• Consensus reading improved sensitivity from 38-63% to 89% in discrepant cases.

Conclusions:

• MDCT is effective for diagnosing malignant cystic renal masses.
• Consensus reading can correct false negative interpretations.
• Specific imaging features (irregular walls/septa, enhancing soft tissue) are reliable indicators of malignancy.