Myelofibrosis and myeloid tumors as a surgical disease

Acute respiratory failure due to extramedullary hematopoiesis

Extramedullary hematopoiesis (EMH) associated with myelofibrosis uncommonly occurs within the thorax. We describe the first reported case of acute and rapidly fatal respiratory failure due to pulmonary interstitial EMH associated with myelofibrosis. Interstitial EMH should be considered in the differential diagnosis of patients with interstitial pulmonary infiltrates and respiratory failure accompanying a disease process known to predispose to the development of EMH.

Osteoclasts and bone remodeling in chronic myeloproliferative disorders. A histochemical and morphometric study on trephine biopsies in 165 patients

In 165 patients with chronic myeloproliferative disorders (CMPD) a morphometric and histochemical study was performed on trephine biopsies of the bone marrow to elucidate osseous remodeling by assessment of trabecular bone area (planimetry) and number of osteoclasts. Osteoclastic elements were identified by the tartrate-resistant acid phosphatase method. In addition to control specimens (n = 20) subtypes of CMPD included chronic myeloid leukemia (CML, n = 65), primary (essential) thrombocythemia (PTH, n = 25), polycythemia vera rubra (P. vera, n = 25) and agnogenic myeloid metaplasia (AMM, n = 50). AMM was discriminated into a so-called early hyperplastic stage without gross myelofibrosis (n = 19) and an overt or advanced stage showing fibro-osteosclerotic changes (n = 31). Total area of trabecular bone and counts for osteoclasts (uni- and multi-nucleated cells as well as a-nuclear cytoplasmic fragments) were not significantly increased in CML, PTH, P. vera and in the initial hypercellular stages of AMM. In contrast to these results, in advanced stages of AMM there was a significant increase in total bone area associated with a high count for all osteoclastic elements and apparently also an increased number of osteoblasts. It is speculated that the marked increase in osteoclastic-osteoblastic elements in late stages of AMM possibly reflects an imbalance of calcitriol (1.25-dihydroxyvitamin D 3) on skeletal homeostasis. This abnormal osseous remodeling may be mediated by the atypical megakaryocytic proliferation in this disorder, which is always a conspicuous feature of bone marrow biopsies.

Osteolytic lesions in idiopathic myelofibrosis

A case of idiopathic myelofibrosis with the unusual finding of osteolytic lesions is presented. Biopsies from the lesions showed proliferation of fibroblasts, megakaryocytes and myeloid cells.

Bronchial extramedullary hematopoiesis preceding chronic myelogenous leukemia

Extramedullary hematopoiesis of the bronchus is rare. The case of a 72-year-old man in whom the right lower lobe bronchus was obstructed by extramedullary hematopoiesis is presented. Ten months after the initial presentation, Philadelphia chromosome-negative chronic myelogenous leukemia was diagnosed. Such findings have not been reported previously. The various anatomic locations of extramedullary hematopoiesis are reviewed, with an emphasis on intrathoracic and pulmonary presentations. The clinical and pathologic features and the differential diagnosis in the present case are discussed.

Megakaryocytes in pleural and peritoneal fluids: prevalence, significance, morphology, and cytohistological correlation

Over a period of 22 years, 4844 pleural and peritoneal fluids from 3279 patients were examined cytologically. Megakaryocytes were found in the fluids from five patients. The clinical diagnoses in the five patients were agnogenic myeloid metaplasia, chronic myeloid leukaemia, and lymphocytic lymphoma. All of these patients had persistent serous effusions. Megakaryocytes in serous fluids occurred in three forms: (1) a large type with abundant cytoplasm and multilobed nuclei, (2) a smaller type with a high nucleocytoplasmic ratio and unlobed nuclei, and (3) anucleate cytoplasmic masses. Foci of agnogenic myeloid metaplasia found on the serous surfaces at necropsy of two patients contained megakaryocytes similar to those in the corresponding effusions. The clinical course of our patients confirmed that the presence of megakaryocytes in serous fluids signifies an advanced haematopoietic malignancy.

Diffuse purely osteolytic lesions in myelofibrosis

In myelofibrosis, the skeletal bones present radiologically as normal or with osteosclerotic or osteoporotic changes. Lytic lesions are very rare and when present are usually associated with osteosclerosis. We report on a case of a patient with myelofibrosis exhibiting diffuse purely osteolytic lesions.

Blastic phase of agnogenic myeloid metaplasia simulating malignant lymphoma

A patient with angogenic myeloid metaplasia in blastic transformation with unusually prominent lymphadenopathy simulating lymphoma is described. Interestingly, the initial evidence of myeloblastic transformation was present in the lymph nodes but not in the marrow. Serial bone marrow biopsies showed fibrosis throughout the course of the disease, in spite of a gradual increase in the percentage of peripheral blood myeloblasts. Aneuploidy with a marker chromosome and a Philadelphia-like chromosome was present in the lymph node, bone marrow, and peripheral blood cells. The literature is reviewed regarding the incidence of prominent lymphadenopathy and chromosome abnormalities in agnogenic myeloid metaplasia and other myeloproliferative disorders.