[Preoperative prediction of gastric cancer development by in vitro labelling index of bromodeoxyuridine]

In vitro labelling index (L.I.) of bromodeoxyuridine (BrdU) was evaluated as a preoperative predictor of gastric cancer development. Biopsy specimens were obtained endoscopically from 187 gastric cancer patients preoperatively. Specimens were incubated in RPMI containing BrdU under carbogen gas at 3 times atmospheric pressure. They were fixed and embedded in paraffin. After slicing and dewaxing, they were denatured in 2N HCl. Then BrdU were stained by ABC method and labelling index was calculated. Patients with L.I. more than 10% had a significantly higher risk of lymph node involvement (p < 0.001) and venous invasion (p < 0.05). Those with L.I. more than 20% had a significantly higher risk of liver metastasis (p < 0.01), while patients with L.I. more than 25% had a significantly higher risk of submucosal invasion (p < 0.01). In conclusion in vitro BrdU labelling is a technique available as a preoperative predictor of node involvement, venous invasion, submucosal invasion and prognosis in gastric cancer.