Use of Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer: Initial Results From the Pembrolizumab Arm of a Phase 2 Randomized Clinical Trial. - Rahma OE; Yothers G; Hong TS; Russell MM; You YN; Parker W; Jacobs SA; Colangelo LH; Lucas PC; Gollub MJ; Hall WA; Kachnic LA; et al. (JAMA oncology, 2021)