Comparative Study Of A Panel Of Conventional Tumor Markers In Paired Samples Of CSF And Serum In Patients Without Central Nervous System Malignant Diseases

Objectives:To learn about the baseline level of a panel of conventional TMs in CSF and relation between TM level in serum and TM level in CSF in patients without malignant diseases. Whether trans-blood-brain-barrier diffusion of tumor marker from serum to CSF exist in patient with elevated level of this kind of tumor marker was also studied.Materials and methods:This study consisted of two parts. In the first part, patients met the following criteria were retrospectively collected.(1) a lumbar puncture for diagnostic purposes was performed.(2) a panel of tumor markers including AFP, CEA, CA125, CA15-3, CA19-9, CA724, CYFRA21-1 and SCC were measured in paired samples of serum and CSF.(3)Levels of tumor marker in serum were within normal limits.We discribed the level of tumor markers in CSF and compared that with their counterparts in serum. In the second part, patients with elevated tumor marker in serum and without central nervous system malignant disease were included. CSF levels of tumor marker elevated in serum were describedResults:In patients without malignant diseases, CSF levels of AFP, CEA, CA125, CA15-3, CA19-9, CA724, CYFRA21-1 and SCC were all extremely low. The mean CSF levels of all eight TMs measured were all significantly lower than those in serum. In all paired samples of serum and CSF, AFP, CEA, CA125 and CA15-3 levels in serum were unexceptionally higher than that in CSF. Similarly, serum levels of CA19-9, CYFRA2-1 and SCC were detected to be higher than that in CSF in a majority of the paired samples. However, in 40.8% of the paired samples, the level of CA724 in serum was lower than that in CSF. In the patients who had increased serum levels of tumor markers and without central nervous system malignant diseases, the CSF levels of corresponding tumor markers were almost not elevated compared with that with normal serum levels of tumor marker.Conclusion:The present study demonstrated the extremely low levels of tumor marker in CSF in patients without malignant disease and with normal serum level of tumor marker. In patients with elevated serum tumor marker, trans-blood-brain-barrier diffusion tumor marker from serum to CSF was not found. The results indicate high specificity of elevated CSF tumor marker in detecting abnormal intrathecal synthesis of tumor marker. Using the reference value of tumor marker for blood as that for CSF was validated.