Multicenter phase II trial (SWOG S1609, cohort 51) of ipilimumab and nivolumab in metastatic or unresectable angiosarcoma: a substudy of dual anti-CTLA-4 and anti-PD-1 blockade in rare tumors (DART) ====================================================================================================================================================================================================== * Michael J Wagner * Megan Othus * Sandip P Patel * Chris Ryan * Ashish Sangal * Benjamin Powers * G Thomas Budd * Adrienne I Victor * Chung-Tsen Hsueh * Rashmi Chugh * Suresh Nair * Kirsten M Leu * Mark Agulnik * Elad Sharon * Edward Mayerson * Melissa Plets * Charles Blanke * Howard Streicher * Young Kwang Chae * Razelle Kurzrock