Predictive Ability of Preoperative CT Scan in Determining Whether the Adrenal Gland is Spared at Radical Nephrectomy

Abstract

Introduction: The aim of this study was to assess whether preoperative multiple detector computed tomography (MDCT) accurately predicts adrenal involvement for patients undergoing non-adrenal sparing radical nephrectomy for renal cell carcinoma. Methods and Materials: A retrospective observational study based on a composite patient population of two university teaching hospitals who underwent radical nephrectomy. Sensitivity, specificity, overall accuracy, positive and negative predictive values and likelihood ratios were calculated from radiological reports. Results: Total 579 patients underwent radical nephrectomy, of which 199 (34.4%) patients underwent a non-adrenal sparing radical nephrectomy, in which 128 (64.3%) were male and 118 (59.3%) were left side tumors. Mean tumor size was 8.2 cm (range 1.4-20cm). MDCT was found to have a sensitivity of 100% and specificity of 95.2% for identifying adrenal invasion. Total 179 patients (89.9%) had a radiographically normal ipsilateral adrenal gland, of which none were found to have adrenal involvement. Therefore, the negative predictive value of preoperative cross-sectional imaging for identification of adrenal involvement was 100%. Conclusion: Cross- sectional MDCT imaging accurately predicts adrenal involvement and the decision to remove or spare the adrenal gland should be made preoperative planning regardless of tumour size or location at the time of multi-disciplinary discussion unless there is intraoperative evidence of adrenal invasion.