The splenomegaly of myeloproliferative disorders: effects on blood volume and red blood count.

By means of a scintigraphic method for estimation of spleen size, the relationship was studied between spleen size and anaemia, total blood volume and red cell volume in patients with myeloproliferative disorders. There was significant correlation between spleen size and Hb, RBC and PCV in myelofibrosis. The size of the enlarged spleen did not, however, correlate with the degree of anaemia in the leukaemias. There was positive correlation between spleen size and red cell volume in these conditions. It was not possible to evaluate the severity of polycythaemia from spleen size and the degree of enlargement of the spleen does not appear to be a reliable parameter for staging and deciding on treatment in patients with PPP.