Pseudouridine determination in blood serum as tumor marker.

A new method to measure pseudouridine (psi rd) in blood serum has been used to study patients with cancer of breast, lung, colon, and ovaries, and patients with hepatomas, non-Hodgkin lymphomas, and acute lymphoblastic leukemias, at different stages. The results indicate: (1) a significant (p less than 0.01) difference between the psi rd serum level of the cancer patient group and the normal control group; (2) that the increase of the level of serum psi rd is correlated both to the stage of the disease and to the spreading of the tumor tissue; (3) a correlation between the response to therapy and the behaviour of psi rd serum levels.