Cell kinetic study of human carcinomas using bromodeoxyuridine.

Cell kinetics in human malignant tumours were studied in vivo using bromodeoxyuridine (BrdU) and immunohistochemistry. BrdU was administered to twenty-four patients with gastric cancer at a dose of 1 g pre-operatively. Specimens were obtained during the operation, fixed in 70% ethanol and embedded in paraffin. BrdU-incorporating cells were detected by immunohistochemical staining using anti-BrdU monoclonal antibody. The labelling index (LI), determined by counting tumour cells microscopically, ranged from 4.0 to 41.4%. The LI was higher at the site of invasion than in the central area of the tumour, but no correlation was found between histological differentiation and LI. The LI of stage I gastric cancer was statistically lower than that of stage II, III and IV gastric cancers (P less than 0.005). This technique, which is less cumbersome and time-consuming than using radioactive isotopes of thymidine, appears to be useful for studying cell kinetics of human malignant tumours.