[A study on BrdU labelling index of gastric cancer using in vitro labelling method]

In order to reveal the effect of environmental factors to BromodeoxyUridine labelling index (BrdU L.I.) and its usefulness as clinicopathological information, 522 specimens obtained from 121 lesions of gastric cancer were studied. Five hundred twenty two specimens in which BrdU had been incorporated using an in vitro labelling method were divided into 3 groups according to their degree of necrosis and cell infiltration. The average L.I. of the specimens with no or slight necrosis was 23.3 +/- 8.7%, medium, 14.2 +/- 10.0%, and severe necrosis, 6.6 +/- 3.8%, with no or slight cell infiltration, 25.3 +/- 9.5%, medium, 21.0 +/- 7.1%, and severe cell infiltration, 21.2 +/- 6.1%, therefore L.I. correlated to necrosis and cell infiltration. Representative values for each lesion were adopted and compared using 3 methods. In method A, a representative value of the L.I. for each lesion was chosen using all biopsy specimens, method B using specimens without necrosis, and method C, specimens without necrosis and cell infiltration. L.I. correlated to stage and the lymphnode metastasis only using methods, B and C and more strictly using method C. Necrosis and cell infiltration should be considered in adopting a representative value of the L.I. for each lesion. Method C is considered to be a best among the three studied, and the L.I. of gastric cancer may be considered a clinicopathological marker.