AUA 2017: Panel Discussion: Advances in Imaging in Urologic Oncology

Boston, MA ( Dr. Damien Bolton presented on PSMA-PET CT and the importance in urologic oncology. He described PSMA-PET as being useful in restaging for a biochemical recurrence and primary staging in high risk disease. He discussed the meta-analysis his group performed for patients for those who had biochemical recurrence the sensitivity and specificity were 86%. For a per-lesion re-staging the sensitivity was 80% and the specificity 97%. For patients with a long PSA doubling time the PSMA positive was 64%, but for a short PSA doubling time (less than 6 months), than the PSMA positivity increased to 92%. However, there were false negatives, not pathologic correlation for most studies and there needs to be further clinical research on how we can use this data in the setting of primary staging and the secondary staging.

Dr. Bedi then discussed contrast enhanced ultrasound (CEUS) which was approved last year by the FDA. He discussed the uses and advantages of CEUS compared to CT or MR. This imaging technology can be used for focal renal masses and other discrete masses (diagnosis, characterization, extent and local invasion during partial nephrectomy and post treatment evaluation). CEUS is different from CT or MR contrast in that they are purely intravascular and microbubble contrast, so it is not nephrotoxic and the dye has a very low toxicity. Once the contrast is injected over the next several seconds contrast saturates lesion of interest. This technology could be helpful for patients with end stage renal disease. The characteristics of contrast uptake may help distinguish types of tumor, but CEUS has not been studied yet in the differentiation of onchocytomas and malignancies. This also may have some utility in bladder and prostate cancer.

Dr. Desai presented on determining if a renal mass is benign or malignant, as well as the biologic behavior. 3D Voxel Mapping gives you cross sectional imaging in four phases so that the full volume of the tumor is able to be calculated with more advanced image analyses. The utility may be to halp differentiate clear cell and papillary tumors. This differentiation is done through analysis of the shape and texture on the imaging. By incorporating the position of each pixel in the imaging for all phases, the biologic characterization of Furhman grading one through four can be determined. A percutaneous biopsy remains gold standard for a diagnosis of renal mass pathology, but perhaps this analysis will help determine future treatment or further workup needed for this patient cohort.

Presented by Mihir M. Desai, MD, University of Southern California, Los Angeles, CA; Damien Bolton, MD from University of Melbourne, Melbourne, Austrailia, Deepak G. Bedi, MD, and Badrinath Konety, MD, University of Minnesota, Minneapolis, MN.

Written By: Janet Baack Kukreja (@janetkukreja), MD, MPH, Urologic Oncology Fellow, Department of Urology, UT MD Anderson Cancer Center, Houston, TX, Ashish M. Kamat, MD, MBBS, FACS, Wayne B. Duddlesten Professor, Department of Urology, UT MD Anderson Cancer Center, Houston TX

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA