1987 Volume 78 Issue 7 Pages 1246-1251
Immunohistochemical study with monoclonal anti Leu-M1 antibody was performed on 25 cases of renal cell carcinoma because it was known that Leu-M1 could be used as a marker for proximal convoluted tubules. The overall positive reaction was observed in 17 out of the 25 cases. 14 out of 16 low grade cases (grade 1 & 2) showed positive reaction, suggesting that renal cell carcinoma was originated from proximal convoluted tubules. One of the negative cases was thought to be derived from distal convoluted tubules because the tumor cells were positive with Tamm Horsfall Mucoprotein. The other negative case was thought to be due to inadequate fixation. 3 out of 9 cases of high grade cases (grade 3 & 4) showed positive reaction, which suggests that Leu-M1 reactivity decreases as dedifferentiation progresses. One of the high grade cases with strong positive reaction showed good response to the treatment. The result of this study indicates that Leu-M1 may be used as a useful marker for evaluatin of renal cell malignancy.