CTLA4 and neoplasm: We also analysed these cases, among which 6.5% cases (five PTC and one ATC) showed co-expression of PD-L1 (in tumour) and CTLA-4 (in TILs), though these cases showed clinicopathologic findings associated with disease progression, including capsular breach (four of six cases), tumour necrosis (five of six cases), lymph node involvement (four of six cases), and OS (three of six cases died of disease within six months of the diagnosis); however, due to the limited number of cases, the findings cannot be concluded.