Increase in serum choline levels predicts for improved progression-free survival (PFS) in patients with advanced cancers receiving pembrolizumab ================================================================================================================================================ * Geoffrey Alan Watson * Enrique Sanz-Garcia * Wen-Jiang Zhang * Zhihui Amy Liu * SY Cindy Yang * Ben Wang * Shaofeng Liu * Shawn Kubli * Hal Berman * Thomas Pfister * Sofia Genta * Anna Spreafico * Aaron R Hansen * Philippe L Bedard * Stephanie Lheureux * Albiruni Abdul Razak * Dave Cescon * Marcus O Butler * Wei Xu * Tak W Mak * Lillian L Siu * Eric Chen