p16 expression was positive in 14.1 % ( 12 of 85 ) , 24.2 % ( 23 of 95 ) , and 19.0 % ( 27 of 142 ) and HPV ISH was positive in 6.5 % ( six of 93 ) , 14.6 % ( 15 of 103 ) , and 6.9 % ( seven of 101 ) of non-OPSCCs from RTOG 0129 , 0234 , and 0522 studies , respectively .