Prognostic factors in myelofibrosis.

The prognostic significance of spleen size, hemoglobin level (Hb), platelet count and hemopoietic cellularity of the bone marrow was assessed in 33 patients with myelofibrosis. Of these 4 parameters, only the Hb (P less than 0.01) and bone marrow cellularity (P less than 0.001) were found to be useful indicators of prognosis. Patients with Hb greater than 10 g/dl had a median survival greater than 110 mth while those with Hb less than 10 g/dl had a median survival of 22.5 mth; patients with hemopoietic hypercellularity in the bone marrow had a median survival greater than 110 mth while those with a normo- or hypocellularity had a median survival of 20.5 mth. There was significant correlation (P less than 0.01) between the marrow cellularity and the Hb level; 71% of patients with a normo- or hypocellular marrow had Hb less than 10 g/dl, while 79% of those with a hypercellular marrow had Hb greater than 10 g/dl.