590 Clinical outcomes and translational analysis of DART S1609: the thyroid cancer cohort; PD-1+ PD-L1+ TIL correlated with favorable survival by Jianhua Zhang, Hong Chen, Cara Haymaker, Elad Sharon, Razelle Kurzrock, Young Kwang Chae, Jiexin Zhang, Jack Lee, Jianjun Zhang, Ignacio Wistuba, Megan Othus, Sarah Fenton, Cristina Rodriguez, Adedayo Onitilo, Ahmad Mattour, Igor Rybkin, Christine McLeod, Helen Chen, Christopher Ryan, Melissa Plets, Charles Blanke, Gheath Al-Atrash, Rajyalakshmi Luthra, Hye Sung Kim, Dzifa Y Duose, Liam Il-Young Chung, Sandip P Patel, Yichen Lu, Edwin Roger Parra, Lorena Isabel Gomez Bolanos, Caddie Laberiano Fernandez, Luisa Solis Soto, Ganiraju Manyam, Gabby Lopez