The value of the initial bone biopsy in chronic myeloproliferative syndromes. Review of 80 cases

In order to review the histological characteristics and to evaluate the presence of valuable findings for diagnostic or prognostic purposes, 80 patients diagnosed of chronic myeloproliferative syndromes (CMPS) who had undergone initial bone marrow biopsy were studied in retrospect. The patients were distributed into 26 cases of chronic myeloid leukaemia (CML), 22 of myelofibrosis (MF), 16 of polycythaemia vera (PV) and 16 of essential thrombocythaemia (ET). The histological findings in the 26 cases of CML consisted of hypercellular bone marrow with fat depletion in all cases; marked thickening of trabeculae was seen in 4 cases and neoformation-like osseous tissue in 7 others. Erythroblastic nests were found in 11 patients, eosinophilia in 23 instances, and abnormal location of immature precursor cells (ALIP) was present in 16 cases. Reticulinic fibrosis was found in 22 patients, collagen fibrosis in 6 and sinusoidal dilatation in 5 cases. Of the 22 MF patients, 8 had normal bone trabeculae, while 14 had trabecular thickening, of moderate degree in 6 cases and marked in 8. Osteoid tissue formation was observed in 21 instances; diminished or absent fat was appreciated in 19 cases. Erythroblastic nests were present in 12 instances, ALIP in 5 and eosinophilia in 14. Reticulin fibres were increased in 22 instances, collagen fibrosis was present in 18 cases, sinusoid dilatation in 12, and lymphoid follicles were seen in 4 patients. Trabecular thickening was found in 15 cases of the PV group (16 patients) and osteoid tissue formation in 2. Fatty tissue was decreased or absent in 11 instances Erythroblastic nests plus eosinophilia were seen in 15 cases, and ALIP in 2.(ABSTRACT TRUNCATED AT 250 WORDS)