The European Society of Medical Oncology (ESMO) congress has grown to be almost as important a its US counterpart, ASCO in terms of establishing which drug trials represent the next breakthrough in patient care. Scrip covers the five key battlegrounds including, GSK challenging AstraZeneca’s Lynparza in the PARP inhibitor class,  Amgen meeting KRAS inhibitor expectations with AMG 510, Merck’s Keytruda intruding on Roche’s Tecentriq, Roche’s trial of Tecentriq for urothelial bladder cancer, and finally Pfizer’s Ibrance facing challenges from Novartis’ Kisqali and Eli Lilly’s Verzenio for treating hormone receptor positive HER2 negative breast cancer.