Progress in cancer care relies on the development of new cancer therapies and on the evolution of techniques for diagnosing and monitoring cancer.
“The words ‘personalized’ and ‘precision’ medicine are used broadly these days, but neither is possible without reliable imaging and tumor biomarker tests,” Daniel F. Hayes, MD, FASCO, FACP, 2016–2017 ASCO president and clinical director of the Breast Oncology Program at the University of Michigan Comprehensive Cancer Center, told the ASCO Daily News.
Advances continue to be made in the development of high-quality diagnostics. In 2016, the U.S. Food and Drug Administration (FDA) approved the novel radioactive diagnostic imaging agent fluciclovine F-18 for PET imaging in men with suspected prostate cancer recurrence based on elevated prostate-specific antigen (PSA) levels after initial treatment.
New Imaging Tool Raises New Questions
The approval of fluciclovine was based on its demonstrated safety and efficacy in two clinical trials. Yet, in a press release, the FDA noted that image interpretation errors are possible with fluciclovine, potentially resulting in false-negative or false-positive results, and clinical correlation of imaging findings is recommended.
Dr. David M. Schuster
The question of what role fluciclovine should play in directing cancer management is a topic of ongoing discussion. Dr. Hayes told the ASCO Daily News that “detection of occult, but impending, metastases in a patient who is otherwise doing well after initial primary and adjuvant therapy is controversial in many diseases.” He said that randomized trials have failed to show a benefit in survival or quality-of-life with this type of strategy in patients with ovarian or breast cancers.
Phillip J. Koo, MD, of Banner MD Anderson Cancer Center and a member of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) Outreach Committee, echoed this concern, noting that the biggest challenge with diagnostic radiopharmaceuticals today is the lack of data regarding their effects on outcomes.
Dr. Koo explained that, currently, the benefit of fluciclovine will be measured by its ability to result in a change in prostate cancer management strategy. However, this is considered to be an intermediate endpoint. Clinical endpoints are needed to fully determine the effects of fluciclovine on patient outcomes. “More studies are in the works to help answer this question,” Dr. Koo said, “but this is always a challenge because fluciclovine is a diagnostic tool.”
David C. Smith, MD, of the University of Michigan, told the ASCO Daily News that the issues that have been raised with the use of fluciclovine in prostate cancer imaging are broadly applicable in hematology and oncology. “It is often assumed that early identification of disease is of benefit to patients,” he said. “However, early identification may trigger additional testing or treatment with attendant side effects but have no impact on survival. In that case, it may not be in the patient’s best interest.”
Despite the unanswered questions regarding the clinical role of fluciclovine, Dr. Schuster pointed out that fluciclovine has demonstrated superiority over conventional imaging, “especially in determining if disease has spread far from the prostate.” He said that these findings may help inform treatment decisions, although “as with any advanced technology, it is best used in specific appropriate situations and not used indiscriminately.”
Interdisciplinary Session to Discuss Imaging Issues
To provide a forum for discussing some of the issues surrounding the accuracy and clinical utility of fluciclovine, ASCO and the SNMMI are hosting a joint session on June 5.* Co-chaired by Dr. Hayes and Sally W. Schwarz, MS, RPh, BCNP, FAPhA, president of the SNMMI and professor of radiology at Washington University School of Medicine in St. Louis, the session will include a panel of experts to discuss the potential applications of fluciclovine in disease management.
Dr. David I. Quinn
Dr. Schuster commented that interdisciplinary discussions between oncologists and imaging specialists are important for exchanging ideas and for a better understanding the requirements and challenges of each other’s respective practices. “Joint meetings such as this one contribute to an atmosphere of team science in which we both learn what are the right questions to ask to inform future development and trials,” Dr. Schuster said.
The session will include a presentation by Dr. Schuster, who will review the scientific basis and clinical data for fluciclovine and discuss real-world examples of the potential benefit of advanced molecular imaging. “This applies not only to this radiotracer but may serve as a framework for the study and approval of other radiotracers at earlier stages in development,” he said.
Session speaker David I. Quinn, MD, PhD, FACP, of the USC Norris Comprehensive Cancer Center, told the ASCO Daily News that value issues related to imaging tests will be another important topic of discussion. “We should use the most definitive imaging test for the situation. We also need to think about the value of routine imaging tests for surveillance in patients who are asymptomatic.”
Overall, session organizers and speakers aim to provide a unique opportunity for attendees to gain new perspectives on the potential applications, benefits, and limitations of new diagnostic tools and to learn about the challenges faced in the development and implementation of advanced technologies. The panel also hopes to promote dialogue between interdisciplinary cancer professionals and provide an essential venue for exchange of ideas to further promote advances in cancer care.
–Mindy Tanzola, PhD
*Program information updated as of March 10. For session time and location information, please refer to the ASCO iPlanner on the Attendee Resource Center.