Ton G. van Leeuwen, Mara Buijs, Jean J.M.C.H. de la Rosette, Peter G. K. Wagstaff, Daniel M. de Bruin, Patricia J. Zondervan, R. Jeroen A. van Moorselaar, Otto M. van Delden, C. D. Savci-Heijink, Maria del Pilar Laguna Pes, CCA - Cancer Treatment and Quality of Life, APH - Quality of Care, APH - Personalized Medicine, Graduate School, Urology, Biomedical Engineering and Physics, Amsterdam Gastroenterology Endocrinology Metabolism, Pathology, Amsterdam Cardiovascular Sciences, Radiology and Nuclear Medicine, and ACS - Atherosclerosis & ischemic syndromes
Background Lack of accuracy in preoperative imaging leads to overtreatment of benign renal masses (RMs) or indolent renal cell carcinomas (RCCs). Optical coherence tomography (OCT) is real time and high resolution, enabling quantitative analysis through attenuation coefficient (μ OCT , mm −1 ). Objective To determine the accuracy and diagnostic yield of OCT and renal mass biopsy (RMB) for the differentiation of benign RMs versus RCC and oncocytoma versus RCC. Design, setting, and participants From October 2013 to June 2016, 95 patients with solid enhancing RMs on cross-sectional imaging were prospectively included. All patients underwent subsequent excision or ablation. Intervention Percutaneous, image-guided, needle-based OCT followed by RMB in an outpatient setting under local anaesthesia. Outcome measurements and statistical analysis Accuracy and diagnostic yield, μ OCT correlated to resection pathology or second biopsy during ablation. Tables (2×2) for RMB, receiver operating characteristic curve for OCT. Mann-Whitney test to differentiate μ OCT of RMs. Results and limitations RMB diagnostic yield was 79% with sensitivity, specificity, positive predictive value, and negative predictive value (NPV) of 100%, 89%, 99%, and 100%, respectively. Diagnostic yield and added value of OCT to differentiate RCC from benign was 99% and 15%, respectively. Significant difference was observed in median μ OCT between benign RMs (3.2mm −1 , interquartile range [IQR]: 2.65–4.35) and RCCs (4.3mm −1 , IQR: 3.70–5.00), p =0.0171, and oncocytomas (3.38mm −1 , IQR: 2.68–3.95) and RCCs (4.3mm −1 , IQR: 3.70–5.00), p =0.0031. OCT showed sensitivity, specificity, positive predictive value. and NPV of 91%, 56%, 91%, and 56%, respectively, to differentiate benign RMs from RCCs and 92%, 67%, 95%, and 55%, respectively, to differentiate oncocytoma from RCC. Limitations include two reference standards and heterogeneity benign RMs. Conclusions Compared with RMB, OCT has a higher diagnostic yield. OCT accurately distinguishes benign RMs from RCCs, and oncocytoma from RCCs, although specificity and NPV are lower. Patient summary Optical coherence tomography, a new optical scan, exhibits similar sensitivity and positive predictive value than renal mass biopsy, although lower specificity and negative predictive value. Optical coherence tomography has a higher diagnostic yield for diagnosing renal cell carcinoma.