ABSTRACT
Plasma cyclic guanosine 3', 5'- monophosphate [cGMP] and urinary excretion of the nucleotide were measured in patients with acute leukemia. Ten patients with acute lymphoblastic leukemia [ALL], ten with acute myetoblastic leukemia [AML] as well as ten healthy controls were enrolled in the study. Samples were measured at presentation and after completion of inducttion chemotherapy. Statistically significant elevated levels of cGMP were found in leukemic patients compared to the controls. Highly significant difference was demonstrated in comparing pre-treatment to post-treatment levels of the nucleotide. A positive correlation was found between the level of plasma cGMP and the blast count in the bone marrow. There was no statistically significant difference between the levels of cGMP in different types of leukemia [ALL versus AML]. In patients who failed to attain complete remission, the level of cGMP remained high and it rised in those who relapsed even before blast invasion. It is concluded that cGMP is a good tumour marker in acute leukemia and it is useful in monitoring response to treatment or relapse