Pathological excretion patterns of urinary proteins in renal cell cancer patients exposed to trichloroethylene

A study was carried out to investigate urinary protein excretion patterns by means of SDS-polyacrylamide-gel-electrophoresis (SDS-PAGE) in renal cell cancer patients who had previously been exposed to high levels of trichloroethylene. Thirty-eight out of 41 (93%) renal cell cancer patients investigated had former extensive trichloroethylene exposure, but only 23 out of 50 (46%) renal cell cancer patients without a history of occupational exposure to trichloroethylene revealed urinary protein patterns indicative of toxic effects on the tubular system. One hundred controls without histories of overt renal disease and not occupationally exposed to trichloroethylene were examined in the same way; only 11 (11%) of them displayed protein excretion patterns indicative of damage to the renal tubule. These results are supported by alpha 1-microglobulin excretion data. The following conclusions are drawn: (1) Substantially more cases of tubular damage are found amongst renal cell carcinoma patients having been exposed to substantial levels of trichloroethylene over many years as compared with renal cell carcinoma patients not exposed to trichloroethylene. (2) The results support the view that chronic tubular damage is a precondition for the nephrocarcinogenic effect of trichloroethylene. (3) The findings indicate that urine protein patterns, on the basis of the SDS-PAGE methodology, represent a 'biological effect parameter' for the medical surveillance of persons occupationally exposed to trichloroethylene.