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Two cases of acute lymphocytic leukaemia associated with bone marrow necrosis – A brief review of recent literature

To the Editor: Bone marrow necrosis (BMN) is a rare phenomenon associated with various haematologic diseases. Especially in acute lymphocytic leukaemia (ALL), BMN is considered to be one of the most important complications. Here, we present 2 patients with BMN at relapse and at post-chemotherapy of ALL, both of which could be confirmed intravitally. The first patient, a 30-year-old woman, who was previously diagnosed as having ALL with early B-precursor phenotype, had a relapse 1 yr after her remission, when she developed moderate jaundice and pain of the posterior iliac crests. Laboratory examination showed elevations of serum bilirubin and lactate dehydrogenase (LDH). The peripheral blood was pancytopenic for haemoglobin of 9.9 g/dl, platelet count of 12 x 109/1 and leucocyte count of 1.5 x 109/1 with 50% lymphoblasts. An attempted bone marrow aspiration resulted in a dry tap and biopsy specimen revealed that haematopoietic cells were eosinophilic and blurry with indistinct margins, which was consistent with marrow necrosis. Subsequently, pancytopenia continued and eventually she died of respiratory failure secondary to pneumonia. The 2nd case was a 51-yr-old female, who had a 4 day history of systemic bone pain, and had marked bone tenderness at multiple areas. Haemogram demonstrated haemoglobin of 12.0 g/dl, platelet count of 73 x 10y/l and leucocyte count of 15.6 x 109/1 with 69.0% leukaemic blasts. The abnormalities of serum chemistry included elevations of LDH and alkaline phosphatase (ALP). The peripheral blasts were classified as L2 morphology and immunophenotypically compatible with common ALL phenotype. The bone marrow specimen on admission showed a hypercellular leukaemic marrow without necrosis, and was cytogenetically found to possess a t(9;22)(q34;qll) designated as the Philadelphia chromosome (Ph ’ ). She was treated with a standard chemotherapy for ALL, and the leukaemic cells rapidly disappeared from the peripheral blood. The second evaluation of bone marrow was performed from the right posterior iliac crest 2 wk after the initiation of chemotherapy, when necrotic materials with decalcification were aspirated. Thereafter, similar results were obtained from the left posterior iliac crest. Bone marrow biopsy from the previous site was found to be a coagulation necrosis. A tumor necrosis factor-r (TNF-a) is reported to be involved in mediating myelonecrosis (1); however, the activities of TNF-a were normal both in serum and supernatant from bone marrow. Bone marrow was examined from the sternum after two and half months, when diagnostic cellular marrow could be obtained. Nevertheless, bone marrow biopsy from the previously necrotic site still remained as a coagulation necrosis. Subsequently, she has had a complete remission 6 months after the diagnosis. BMN is a necrosis of myeloid tissue and medullary stroma, involving large areas of bone marrow and often diagnosed at autopsy (2). The main clinical pictures of BMN are known to be severe pain and tenderness of bone. Laboratory findings are characterized by peripheral pancytopenia, leucoerythroblastic anaemia, and elevation of serum LDH, ALP or uric acid. We reviewed the literature concerning BMN associated with haematologic malignancies from 198 1 up to the present. Including our present patients, a total of 49cases have been reported (1 9 acute nonlymphocytic leukaemia (ANLL), 24 ALL, 2 chronic myelogenous leukaemia (CML) and 4 other haematologic neoplasms). Thus, acute leukaemias appear to be often associated with BMN, and there is no significant difference in the frequency of marrow necrosis between ANLL and ALL. In the case of ALL, L1 morphology is much more frequently complicated by myelonecrosis than L2 type, reflecting a close association of BMN with childhood ALL. Additionally, ANLL with a monocytic property corresponding to M4 or M5 subtype is more often complicated by marrow necrosis than the other types of ANLL. Here, we report 2 BMN cases developing at relapse or at post-chemotherapy of ALL. The prognosis of our 2 cases showed a remarkable