Use of targeted next generation sequencing to characterize tumor mutational burden and efficacy of immune checkpoint inhibition in small cell lung cancer ========================================================================================================================================================= * Biagio Ricciuti * Sasha Kravets * Suzanne E. Dahlberg * Renato Umeton * Adem Albayrak * Safiya J. Subegdjo * Bruce E. Johnson * Mizuki Nishino * Lynette M. Sholl * Mark M. Awad