[Significance of measurement of serum and cerebrospinal fluid trace elements in the diagnosis of brain tumors].

Cu, Zn, Cd, Mn, Se in serum and Cu, Cd and Mn in cerebrospinal fluid (CSF) of 150 patients were measured by flame, flameless and hydride generation atomic absorption spectrophotometry. The patients were divided into three groups: malignant brain tumor group (MTG), benign brain tumor group (BTG), and non-neoplastic neurological disease group (no evidence of brain tumor group, NENG). The results were as follows: 1. Serum Cu, Zn, Cd, Mn, Se levels before operation were higher than those after operation; 2. Cu Cd, Mn serum levels were positively correlated with the CSF in the three groups. The correlation coefficients of serum Cu-CSFCU were 0.8935 (MTG), 0.6074 (BTG), 0.5349 NETG); serum Cd-CSFCd 0.7963, 0.2671, 0.5398; serum Mn- CSF Mn 0.5855, 0.4474, 0.5163, (P less than 0.01). 3. Serum and CSF Cu levels in MTG were significantly higher than in BTG and NETG (P less than 0.01). 4. A group of discrimination function equations was established with stepwise discrimination analysis. The six factors, i. e. serum Cu, Cd, Mn, Se and CSF Cu, Mn were significant in the equations. The conformation rate of diagnosis and discrimination by the equations in the malignant and benign brain tumors with clinical diagnosis was 81 percent. The equations could describe the relationship of coordination and antagonism among trace elements in serum and CSF. The authors believe that discrimination equations may have potential use both in diagnosing and discriminating patients in the 3 groups mentioned above and in following patients after excision of the brain tumor.