During the closing plenary, Lewis C. Cantley, PhD, FAACR, Chairperson of the 2015 Annual Meeting Program Committee, discussed key basic research presentations. These included numerous studies investigating genetic diversity among different cells isolated from a single tumor and among tumors isolated from different sites in a single patient. He emphasized the critical value of mapping this genetic heterogeneity and understanding how it evolves because the information is vital to understanding and overcoming treatment resistance. Cantley also highlighted presentations that revealed mechanisms of resistance to specific molecularly targeted therapies and how a combination of basic research approaches — including proteomics, systems biology, organoids, and CRISPR-Cas9 technology — are being used to overcome this challenge and catalyze the development of new targeted therapies.

Carlos L. Arteaga, MD, FAACR, AACR president 2014–2015, then reviewed the groundbreaking clinical and translational research presented at the meeting. He began with several studies on an immunotherapy approach known as checkpoint blockade, including two that subsequently led to approvals by the U.S. Food and Drug Administration (FDA). The first study was the phase III clinical trial presented in the Opening Plenary session by Antoni Ribas, MD, PhD, which showed that pembrolizumab (Keytruda) yielded significantly better outcomes than ipilimumab (Yervoy) when it was the first treatment given to patients with advanced melanoma. These results later led the FDA to approve the use of pembrolizumab for use in this setting. The second practice-changing study was presented by Stephen Hodi, MD, who showed that giving the two immunotherapies ipilimumab and nivolumab (Opdivo) simultaneously yielded better treatment responses than ipilimumab alone for patients with advanced melanoma who had received no prior treatment. These data and follow-up analysis led the FDA to approve this immunotherapy combination in late September.

Arteaga also highlighted several studies in the area of predictive genomics — the use of genomics to identify those patients most likely to respond to a particular therapeutic. Recalling the challenges of tumor heterogeneity discussed by Cantley, he stressed the importance of collecting genomic information from more than one site of metastasis. Arteaga closed with a discussion of several presentations detailing the potential of liquid biopsies as a viable alternative to tumor tissue biopsies for genomic analysis.

William G. Nelson, MD, PhD, editor-in-chief of Cancer Today, highlighted key presentations on cancer prevention research, in particular those in the emerging field of precision prevention and early detection. He initially focused on studies developing and using molecular tools for screening and early detection, such as the DNA stool test for colorectal cancer, and went on to discuss the use of genomics to identify individuals who are at highest risk for certain cancers and might benefit from chemoprevention approaches such as taking aspirin for colorectal cancer prevention. Nelson concluded his summary with studies suggesting that the microbiome has an important role in cancer biology, focusing on preclinical data showing that a particular bacterium promotes colorectal cancer development in a mouse model of the disease.

José Baselga, MD, PhD, FAACR, AACR president 2015–2016, concluded the session with a vision for the future — a future in which the promise of precision medicine, immunotherapy, and the harnessing of big data is fully realized.