Recently, the study of the physiological role of the essential trace elements is being emphasized. Some environmental and disease factors has been demonstrated to perturb trace element homeostasis. A number of recent studies have described alterations in serum copper levels (SCLs) and serum zinc levels (SZLs) in human cancer patients and the relationship between the magnitude of their perturbation and disease activity. This report describes SCLs, SZLs and SCL/SZL ratios in patients with malignant neoplasms of the urogenital tract at various clinical stages and the relationship of the levels of these trace elements to disease activity. According to SCLs before treatment, patients with renal cell carcinoma appeared to be separated into two groups, normal SCL group and higher SCL group. In the higher SCL group, patients generally displayed increased erythrocyte sedimentation rate, CRP, alpha 2 globulin, beta 2 microglobulin, ferritin and CEA. In this group, SCL was a useful index of disease activity. In the normal SCL group, SCLs remained within normal limit even in patients with advanced disease. In renal cell carcinoma, SZLs did not reflect disease activity. In transitional cell carcinoma of the upper urinary tract, patients with metastasis had significantly elevated SCLs and significantly decreased SZLs, compared with normal controls or patients without metastasis. In transitional cell carcinoma of the bladder, no distinct relationships were observed between these trace elements and extent of malignancy. But there was a trend toward increasing SCLs and decreasing SZLs with progressing stage and SCL/SZL ratios fairly reflect stage of disease. Patients with prostatic cancer had nearly normal SCLs and SZLs, although there were a few exceptions. Testicular cancer patients with distant metastasis had significantly elevated SCLs and initially high SCLs decreased in patients responding to therapy and increased again in relapse. SZLs and, hence, SCL/SZL ratios had no relationship to activity of testicular cancer. Currently there is no satisfactory way of following the progress of malignancies of the urogenital tract except prostatic cancer with elevated acid phosphatase and non-seminomatous testicular tumors until the secondary tumor can be detected radiographically. Our study suggests that these trace element might be a useful indicator of disease activity of some of the urogenital malignancies.