%0 Journal Article %A Bernard Paule %A Jacqueline Belot %A Christiane Rudant %A Colette Coulombel %A Claude Clément Abbou %T The importance of IL-6 protein expression in primary human renal cell carcinoma: an immunohistochemical study %D 2000 %R 10.1136/jcp.53.5.388 %J Journal of Clinical Pathology %P 388-390 %V 53 %N 5 %X Aims—Interleukin 6 (IL-6) is produced by some renal carcinoma cell lines in vitro. This might be biologically important because IL-6 is a cytokine of particular interest, owing to its involvement in the growth of renal cell carcinoma. In this study, the expression of IL-6 protein in tissue samples from primary renal cell carcinoma was analysed, and then its clinical importance was examined. Methods—The distribution of IL-6 in renal cell carcinoma was examined by means of an immunohistochemical method in 47 untreated primary renal cell carcinoma samples. The search for a significant difference between histological patterns, Furhman's grading system, TNM classification, and IL-6 protein expression was carried out. Results—Immunohistochemistry demonstrated that IL-6 is expressed in 70% of primary tumours. There was no significant difference in the tumour size and grade between renal cell carcinomas with or without IL-6 expression. However, a relatively large number of high grade tumours expressed IL-6. Conclusion—The importance of IL-6 expression with regard to tumour size/local growth is questionable because IL-6 has been correlated with the development of metastatic disease. These data suggest that the production of IL-6 could exert a growth inhibitory effect on primary renal cell carcinoma. %U https://jcp.bmj.com/content/jclinpath/53/5/388.full.pdf