Bone marrow histopathology in primary myelofibrosis: clinical and haematologic correlations and prognostic evaluation.

In 51 patients with primary myelofibrosis the initial bone marrow biopsy findings were evaluated by morphometric methods, correlated with the patients' main clinical and haematologic data and analysed for prognostic significance. The high variability of the marrow features was the most striking finding of the morphologic study. The only remarkable clinico-pathological correlation was that found between the extent of stromal proliferation in the bone marrow and the number of WBC precursors in peripheral blood. Classical bone marrow histologic patterns did not correlate with the main clinical or haematologic data nor did they influence the patients' survival. Finally, collagen fibrosis and abnormal clusters of immature myeloid precursors were the only histologic features showing an unfavourable prognostic significance at the multivariate study.