Mittul Gulati MD, Presenter: Nothing to Disclose

Steven Satish Raman MD, Abstract Co-Author: Nothing to Disclose

Nagarajan Rajakumar PhD, Abstract Co-Author: Nothing to Disclose

Ana Maria Gomez, Abstract Co-Author: Nothing to Disclose

Michael Albert Thomas PhD, Abstract Co-Author: Nothing to Disclose

David Shin-Kuo Lu MD, Abstract Co-Author: Consultant, Siemens AG Consultant, EZM Incorporated Consultant, Vital Images, Inc Consultant, General Electric Company Speaker, General Electric Company Consultant, RITA Medical Systems, Inc Speaker, RITA Medical Systems, Inc Consultant, Boston Scientific Corporation Speaker, Boston Scientific Corporation Consultant, Endocare, Inc Research funded, Endocare, Inc Consultant, Tyco Healthcare (Valleylab) Speaker, Tyco Healthcare (Valleylab) Research funded, Tyco Healthcare (Valleylab)

Robert E. Reiter MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

MRI/MRSI are increasingly used for preoperative staging of prostate cancer. We identified cases where imaging findings helped plan robotically assisted laparoscopic radical prostatectomy (RALRP).

Unlike clinical variables (digital rectal exam (DRE) and serum PSA level), MRI/MRSI results are spatially localized, offering the potential for individually tailored surgery. Knowledge of extracapsular extension (ECE) of cancer should prompt wide resection of the involved prostatic capsule and NVB. On the other hand, in prostate-confined cancer, the NVBs should be spared in order to preserve patient potency. Preoperatively determining ECE is especially relevant prior to RALRP, in which the surgeon has no tactile feedback to gauge tumor extent. We retrospectively evaluated records of 21 prostate cancer patients who underwent endorectal MRI/MRSI prior to RALRP. A GE 1.5T Echospeed MRI scanner was used, and MRI protocol included multiplanar T1- and T2-weighted imaging. MRSI included 3D water and fat suppressed spectroscopic acquisition. We determined accuracy of MRI/MRSI in predicting ECE, using post-prostatectomy surgical pathology as a gold standard.

The sensitivity and specificity of MRI for determining ECE were 83% and 93%, respectively. Positive and negative predictive values of MRI for predicting ECE were 83% and 93%, while accuracy was 90%. Significantly, in 5 of 21 patients undergoing RALRP, imaging demonstrated ECE and unilateral NVB involvement. None of these 5 cancers were palpable on DRE, and ECE would have been undetected in the absence of MRI/MRSI. Operative reports showed that imaging guided the surgeon to widely resect the involved NVB and prostatic capsule and achieve negative surgical margins in all 5 cases. Patients were aware that their NVB had to be resected, decreasing their chance of postoperative potency.

MRI/MRSI was excellent at staging prostate cancer prior to RALRP. This is the first report utilizing imaging to plan NVB resection in RALRP, which is significant given the increasing prevalence and lack of tactile feedback during RALRP.

MRI/MRSI can be used as valuable adjuncts when planning to resect or spare vital structures during RALRP.

Gulati, M, Raman, S, Rajakumar, N, Gomez, A, Thomas, M, Lu, D, Reiter, R, et al, , et al, , Novel Use of MRI/MRSI in Planning Robotic Radical Prostatectomy: Report of Experience with Histopathological Correlation.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5005671.html