Background Modified nucleosides , and polyamines were used as biochemical markers in the investigation of the neoplastic diseases ,whereas there is a growing concern about the possible links between some trace elements and tumors of various organs and tissues. This Biochemical study was done in Al-Kadhymia Teaching Hospital in period betwee 10/9/2002 and 1/9/2003. Objectives To determine the changes in serum levels of modifed nucleosides (pseudouridine ) , polyamines , and some trace elements in patients with benign prostatic hyperplasia , prostatic cancer , and bladder cancer to identify the role of these markers in discrimination between benign & malignant proslatic tumors and in the detection of bladder cancer. Methods : A total of 95 patients (41 with benign prostatic hyperplasia , 7 with prostate cancer, and 47 had bladder cancer) were involved in the study . Thirty apparently healthy adults as a control group were also involved in the study . Serum concentrations of pseudouridine ,polyamines (spermidine & spermine) were measured by high performance liquid chromatography (HPLC) . The serum levels of Magnesium (Mg) , Manganese (Mn) ,Zinc (Zn) , Chromium(Cr) ,Cadimum (Cd) ,Copper (Cu ) .Cobalt (Co) & Vanadium (V ) were determined by flame atomic absorption spectrophotometer whereas , the serum Se & Ge levels were analyzed by the llamless atomic absorption spectrophotometer . Results: ng/ml The mean serum pseudouridine (\|/) , spermidine (Sd) and spermine (Sp) values for the control group were 0.59 ±0.20 ng/inl , 0.06 ± 0.03 and 0.02±0.004 ng/ml respectively . For benign prostatic hyperplasia were 1.31 ±0.18 ng/ml, 0.0748 ± 0.004 ng/ml ,0.0348 ± 0.004 ng/ml , in an order . For prostate cancer were 1.5 ±0.012 ng/ml , 0.08± 0.006 ng/ml, 0.039 ± 0.005 ng/ml ^respectively and for bladder cancer were 2.0115 ± 0.20 ng/ml , 0.1597± 0.005ng/ml , and 0.2054± 0.005 ng/ml,one by one .These parameters demonstrate significant elevation in patient groups as compared to the control group with significant differences between different stages (stage I,II,III, IV) of the bladder cancer ( p<0.01 , PO.001 ,p<0.001 ,and p<0.01 , respectively ). Patients with benign prostatic hyperplasia ,prostate cancer,and bladder cancer have significantly lower serum levels of Mg,Mn,Zn,Cr,Co,Se,Ge (p<0.01) in comparison to the controls .In contrasts,the mean serum levels of Cu,Cd,&V were signifocantly elevated in the patients groups as compared to the control group. Conclusion: Pseudouridine and polyamines measurment can be used as and confirmatory tests for the diagnosis and follow up of patients with bladder cancer.Alterations in the serum levels of some trace elements may be utilized as additional markers in the assessment of bladder and prostate tumors .