More than 2,900 attendees gathered for the 11th annual Genitourinary (GU) Cancers Symposium, held February 26-28, in Orlando, Florida, with more than half the attendees hailing from outside of the United States. During the 3-day Symposium, attendees exchanged ideas, best practices, and scientific research that will lead to future progress in GU cancers. Reflecting the meeting’s theme, “Integrating Biology into Patient-Centric Care,” this year’s sessions featured several key studies pulled from the more than 640 abstracts submitted by researchers from around the globe.
Social media continued to play a large role in enabling attendees to share information with the public and connect with one another and the larger cancer community. Using the hashtag #GU15, users sent out more than 2,000 tweets. (For more information on social media presence at the GU Symposium, see the infographic.)
Commenting on the breadth of research at this year’s Symposium, Christopher P. Evans, MD, of the University of California, Davis, Comprehensive Cancer Center and 2015 GU Cancers Symposium Steering Committee chair, said, “We took the theme to heart in how we set up the program, in that we had biology integrated into each section along with the clinical aspects, so that the panels and conversations that ensued encompassed both the biology, the translational science, and the clinical application of patient care.”
Adjuvant treatment of renal cell carcinoma
The data presentation causing the largest stir at the GU Symposium was the report on the phase III ASSURE trial, the first study to evaluate the efficacy of multitargeted VEGF inhibitors in the adjuvant setting for patients with locally advanced renal cell carcinoma at high risk of recurrence. Results demonstrated that neither sorafenib nor sunitinib offered benefits above and beyond those of placebo in the adjuvant setting. Time to disease recurrence after surgery reached 5.6 years with either sorafenib or sunitinib, as compared with 5.7 years with placebo. In addition, 5-year disease-free survival rates and 5-year overall survival (OS) rates ranged little between sorafenib, sunitinib, and placebo.
Radiation therapy and hormone therapy for localized prostate cancer
ASCENDE-RT (Androgen Suppression Combined with Elective Nodal and Dose Escalated Radiation Therapy), pushed the treatment envelope in localized prostate cancer by delivering higher radiation therapy doses via low-dose rate brachytherapy (LDR-B) and administering androgen deprivation therapy (ADT) for 12 months in patients with intermediate- or high-risk nonmetastatic disease. The findings revealed that LDR-B resulted in a 50% reduction in the risk of biochemical relapse compared with an external-beam conformal boost (DE-EBRT) in the context of ADT and pelvic EBRT—the first time this has been demonstrated in a randomized trial. The biochemical progression-free survival (PFS) rates for the LDR-B and DE-EBRT arms, respectively, were 88.7% versus 83.8% at 5 years, and 83.3% versus 62.4% at 9 years. Notably, the trend favoring LDR-B over DE-EBRT for improved biochemical PFS held steady in both the intermediate-risk and high-risk patient groups.
Commenting on this study, Daniel A. Hamstra, MD, PhD, of the University of Michigan Health System and chair-elect of the 2015 GU Cancers Symposium, said, “These results are potentially game-changing in terms of how we’re going to treat patients. It’s the first level 1 evidence that we’ve had that brachytherapy provides a substantial improvement in disease control as compared to dose-escalated EBRT.”
Systemic therapy for prostate cancer
Previous research tied androgen receptor splice variant 7 (AR-V7) to resistance to both enzalutamide and abiraterone in metastatic castration-resistant prostate cancer (mCRPC); the truncated form of AR-V7 lacks the ligand-binding domain targeted by androgen antagonists. In a new study, the presence of AR-V7 in circulating tumor cells did not correlate with primary resistance to taxane chemotherapy. Among patients negative and positive for AR-V7 who received taxane, best prostate-specific antigen (PSA) response rates reached 65% and 41%, respec-tively, which did not differ significantly between arms in this small prospective study of 37 patients. PSA PFS and clinical/radiographic PFS following taxane chemotherapy also turned out to be comparable between the AR-V7–negative and AR-V7–positive groups. Thus, these initial data suggest that AR-V7 may serve as a useful treatment selection marker in patients with mCRPC by indicating which patients may benefit from antiandrogens and which would fare better with taxane chemotherapy.
Results from the international phase III COMET-1 trial, which compared cabozantinib versus prednisone in patients with mCRPC previously treated with docetaxel and antiandrogens, also turned out negative, but with potential positive signals in select patient subgroups. In the final analysis of the 1,028 patients who participated in the trial, median OS was 11.0 months with the antiangiogenic agent versus 9.8 months with prednisone, a difference that did not reach statistical significance (cabozantinib did yield significant improvements in the 12-week bone-scan response, PFS, and time to the first skeletal-related event, among other endpoints, in comparison with prednisone).
Increased Networking and CME Opportunities
The 2015 meeting featured several new programs, including Audio Poster Tours, Electronic Question and Answer (eQ&A), and the Message and Networking Center, which allowed attendees to connect and interact with one another, both in person and virtually.
For the first time, this year’s GU Symposium featured Audio Poster Tours, in which expert faculty discussed selected posters via podcast for the three Poster Sessions. Attendees could stream or download the Audio Poster Tours and scan the QR code displayed on select posters with their smartphone. The expert faculty who narrated the poster tours included: A. Oliver Sartor, MD; Noah M. Hahn, MD; Stacy Loeb, MD; and Eric Jonasch, MD.
Attendees connected with one another through the new Message and Networking Center, a tool accessed through the Attendee Resource Center that facilitates quick, convenient communication with other attendees. Attendees could search the Symposium attendee list to find out if colleagues were attending the meeting, see a list of suggested attendees they might know, and send private messages.
Also for the first time, all General Sessions at the GU Symposium used eQ&A, an interactive feature that enabled participants to ask questions via text or web submission using their mobile phones, tablets, or laptops.
Expanded continuing education credits for 2015
American Board of Internal Medicine (ABIM) diplomates who attended the Symposium were able to earn up to 10 Maintenance of Certification (MOC) points. After registering online or onsite at the meeting, attendees had the opportunity to take an online pretest that identified learning gaps and suggested a list of sessions that addressed those gaps. After the Symposium, attendees were able to take a post-test that allowed them to claim 10 MOC points, with the option of sending results directly to the ABIM.
Mark Your Calendar for the 2016 GU Cancers Symposium
Save the date for the 2016 Symposium, scheduled for January 7-9, in San Francisco. To accommodate a growing number of attendees, the Symposium will be moving to a new, larger venue at the Moscone Convention Center, West Building in downtown San Francisco. Abstract submitter, registration, and hotel reservations will open in late July.
Access complete Genitourinary Cancers Symposium Daily News coverage.