RSNA 2006 

Abstract Archives of the RSNA, 2006


SSJ06-03

Role of Lymphotrophic Nanoparticle Enhanced Magnetic Resonance Imaging (LNMRI) to Identify Lymph Node (LN) Metastases in Recurrent Prostate Cancer (CaP) Patients, Candidates for Salvage Radiation Therapy (SXRT)-Preliminary Data

Scientific Papers

Presented on November 28, 2006
Presented as part of SSJ06: Molecular Imaging (Lymph Nodes)

Participants

Robert W Ross MD, Presenter: Nothing to Disclose
Anthony Zietman MD, Abstract Co-Author: Nothing to Disclose
John Coen MD, Abstract Co-Author: Nothing to Disclose
Marta Braschi MD, Abstract Co-Author: Nothing to Disclose
Ralph Weissleder MD, PhD, Abstract Co-Author: Stockholder, VisEn Medical, Inc Consultant, Siemens AG
Mukesh Gobind Harisinghani MD, Abstract Co-Author: Nothing to Disclose

PURPOSE

LNMRI using magnetic nanoparticles (CombidexÒ, Advanced Magnetics) is able to identify metastatic LN involvement in patients with high risk, localized CaP prior to radical prostatectomy with a positive predictive value of > 94%. The purpose of this study was to identify LN involvement using LNMRI in men with a rising prostate specific antigen (PSA) and who are candidates for SXRT.

METHOD AND MATERIALS

Eighteen patients have been enrolled to date in an ongoing clinical trial of LNMRI in men with rising PSA post-RP, candidates for SXRT. Inclusion criteria include PSA < 4.0 ng/ml, no metastatic disease or LN involvement by bone scan or computed tomography (CT) scan, and no history of XRT or androgen deprivation therapy. All eligible, consented subjects underwent an LNMRI. “Positive” LN subjects underwent a CT-guided biopsy if feasible. Enrollment is planned for 40 subjects. This report is of the LNMRI results of the first subjects enrolled, without clinical follow-up.

RESULTS

Of the 18 enrolled patients; 9 (50%) had a Gleason grade of 7 at RP (range 6-9). 7 (39%) had positive margins at RP. 1 (6%) had seminal vesicle invasion. 10 (56%) had a LN dissection as part of their RP. Mean PSA at enrollment was 0.96 ng/ml (range 0.3 – 3.7). 2 (11%) subjects had adverse reactions during the infusion of the contrast or in the 3 hour follow-up period (both were Grade 1 allergic reactions and flushing). 4 (22%) had LNMRI evidence of LN metastatic disease – one subject had 4 suspicious nodes (obturator, perirectal, presacral and hypogastric, the largest 7 mm in size) and all the other subjects had one suspicious node each (obturator node of 3.5 mm, presacral node of 5 mm, para-aortic node of 5 mm). One of these nodes was biopsied and found to be benign; all the other nodes were too small to biopsy. Long-term outcome data is pending.

CONCLUSION

LNMRI is associated with few adverse in this patient population. The location of the recurrent LNs in these post-RP subjects is varied.

CLINICAL RELEVANCE/APPLICATION

The proportion of subjects with positive nodes is high enough to be clinically relevant, although conclusions regarding its clinical usefulness will require completion of this ongoing trial and long-term follow-up data.

Cite This Abstract

Ross, R, Zietman, A, Coen, J, Braschi, M, Weissleder, R, Harisinghani, M, Role of Lymphotrophic Nanoparticle Enhanced Magnetic Resonance Imaging (LNMRI) to Identify Lymph Node (LN) Metastases in Recurrent Prostate Cancer (CaP) Patients, Candidates for Salvage Radiation Therapy (SXRT)-Preliminary Data.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4438089.html