Liver involvement at diagnosis of primary myelofibrosis: a clinicopathological study of twenty-two cases.

Liver biopsies were carried out at diagnosis in 22 patients with primary myelofibrosis. Pathological changes were semiquantitatively evaluated and correlated with either liver function tests, peripheral blood features, bone marrow biopsy changes or patient survival. Hepatic myeloid metaplasia (HMM), primarily consisting of the presence of morphologically abnormal megakaryocytes, was found in all cases. Other remarkable pathological changes included increased reticulin network, sinusoidal widening not related to the intensity of HMM, and iron overload in the absence of previous blood transfusions. High serum alkaline phosphatase was the most frequent biochemical abnormality, and reflected rather the presence of sinusoidal widening than the degree of HMM. The number of immature myeloid cells was the only peripheral blood parameter positively correlated with the degree of HMM. No relationship could be established between bone marrow changes and the degree of HMM. Finally, patients with mild HMM survived longer than those showing marked HMM.