How Accurate Is Diagnostic Imaging in Determination of Size and Multifocality of Renal Cell Carcinoma as a Prerequisite for Nephron-Sparing Surgery?

Abstract

BACKGROUND: The indication for elective nephron-sparing surgery (NSS) in renal cell carcinoma (RCC) is under discussion in the urological literature. The main problem of NSS is the multifocality of RCC. The presented study was performed to asses the accuracy of pre- and intraoperative ultrasound (US), and computerized tomography (CT) in determination of tumor size and detection of multifocal lesions. MATERIALS AND METHODS: Tumor size was measured by preoperative US and CT and compared with the tumor diameters in gross sections of the neoplastic kidneys. Multifocality was determined by 3-mm step sectioning of the nephrectomy specimen, and the results were correlated with preoperative US and CT on the one hand, and the ex situ sonography of the nephrectomized kidney on the other hand. RESULTS: US and CT show similar results in the determination of the tumor size. In only 22.9%, preoperative US and CT were able to detect multifocal tumors. Ex situ sonography had a sensitivity of 40.0% and a specificity of 87.2% in this regard. CONCLUSIONS: In preparation for nephron-sparing surgery of renal cell carcinoma, neither preoperative routine imaging, nor intraoperative ultrasound can safely predict multifocal lesions of renal cell carcinoma.