Change of macrophage migration inhibitory factor: possible indicator for postoperative prognosis.

Sixty three cancer cases who received minimum of the removal of the main tumor constitute the subjects of the present study. Macrophage migration inhibitory factor (MIF) of peripheral blood lymphocytes was studied using extirpated autochthonous tumor tissues as antigen and guinea-pig peritoneal exudative cells as indicator cells immediately before the operation and the fourth postoperative week. The results indicated that in those cases of relatively early stage, i.e. Stages I and II, whose tumor was believed to have been removed completely, MIF turned negative in 7/9 (77.8 per cent) after the operation, while in others with advanced cancer of Stage IV in which the tumor bearing tissue was probably not completely removed, MIF turned positive in most cases (13/17: 75.6 per cent) postoperatively, even though it was negative before the operation. In the cases of Stage III with cancer progressed to an intermediate degree, in about half of the cases (7/11: 63.6 per cent) MIF turned negative after the operation and in the other half (7/10: 70 per cent) MIF became positive postoperatively, suggesting that for MIF to persist the presence of certain amount of tumor tissue is necessary.