HLA-DR EXPRESSION AND LYMPHOCYTIC INFILTRATION IN METASTATIC AND NONMETASTATIC PAPILLARY CARCINOMA OF THE THYROID

Thyrocyte HLA-DR expression in association,vith lymphocytic infiltrati on has been demonstrated in autoimmune diseases of the thyroid, HLA-DR expression has been noted both in association with lymphocytic infilt ration and in its absence, However, no prognostic significance was att ributed to these findings, The purpose of this study on papillary carc inoma of the thyroid was to examine how tumour behaviour relates indep endently to HLA-DR expression and lymphocytic infiltration, Fifty pati ents with papillary carcinoma with known metastatic status mere examin ed for HLA-DR expression utilizing the immunoperoxidase conjugated ind irect method, The patients were divided into three groups: no metastas es (rr = 16), regional lymph node metastases only (n = 25), and distan t haematogenous metastases (n = 9), Overall HLA-DR expression was note d in 6, 36 and 55% of the respective groups, Tumour HLA-DR expression without lymphocytic infiltration was noted in 0, 4 and 33% of the resp ective groups, Tumour KLA-DR expression with lymphocytic infiltration occurred in 6, 32 and 22% of the respective groups, From these finding s me conclude that HLA-DR expression with lymphocytic infiltration occ urs more frequently than HLA-DR expression in the absence of infiltrat ion, The concurrence of HLA-DR expression and lymphocytic infiltration is most commonly associated with regional lymph node metastasis, KLA- DR expression in the absence of lymphocytic infiltration occurs in rum ours with distant haematogenous metastases and is an uncommon feature of tumours that have not metastasized or have metastasized only to lym ph nodes, Tumour HLA-DR expression in the absence of lymphocytic infil tration may indicate the potential for more aggressive behaviour.