Masahito Yumura

Preoperative cell-mediated immune status of gastric cancer patients

The status of cell‐mediated immunity was studied in 360 patients with gastric cancer before surgery. For the skin test, tuberculin and DNCB were employed. For the in vitro test, the blastogenesis of peripheral blood lymphocytes to phytohemagglutinin (PHA), the ratio of rosette‐forming T cells to sheep blood red cells, and the macrophage migration inhibitory factor against autochthonous tumor antigens were measured. As a result, it was found that in progressive gastric cancers the cell‐mediated immunity decreased specifically or nonspecifically, especially the DNCB reaction; and the blastogenesis against PHA showed an inverse correlation to the advance of gastric cancer.

Ratio of Branched Chain Amino Acid to Tyrosine After Hepatectomy

The roles of branched chain amino acids (BCAAs) and the tyrosine (Tyr) profile after liver resection were investigated using an inexpensive enzymatic method that was recently developed to quantify their concentrations. The preoperative BCAAs-to-Tyr ratio (BTR) was significantly correlated with the preoperative indocyanin green clearance ratio. The BTR decreased immediately after surgery in all patients, but it was significantly lower in those who had undergone major hepatectomies. After the infusion of BCAA-enriched amino acid solution, the BTR increased substantially, being significantly higher in patients who had not suffered an elevation in total bilirubin after liver resection. These findings indicate that this new enzymatic method to quantify the concentration of BCAAs and Tyr is useful to control the infusion of amino acids and to study the role of amino acid metabolization during the perioperative period.

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.