Massive bone marrow necrosis associated with Waldenström’s macroglobulinemia

AbstractHere, we report a rare case of massive bone marrow necrosis, which – from the clinical findings and images – mimics disseminated bone metastasis. The patient was suffering from severe bone pain with elevated levels of serum alkaline phosphatase (ALP) and lactate dehydrogenase (LDH); moreover, strong incorporation of 18F-fluorodeoxyglucose in multiple bones was observed by positron emission tomography/computed tomography.The underlying disease was Waldenström’s macroglobulinemia, which was thought to transform to cluster of differentiation 5 (CD5)-positive diffuse large B-cell lymphoma (DLBCL). The case showed a highly aggressive course, although the original Waldenström’s macroglobulinemia was in the stable state.Clinicians should be aware of the co-occurrence of non-immunoglobulin-producing immature lymphoma, even with good course of Waldenström’s macroglobulinemia, and should pay attention to accompanying massive bone marrow necrosis, which mimics multiple cancer metastases to the bone. To the best of our knowledge, the present case is the first report of CD5-positive DLBCL transformed from CD5-negative Waldenström’s macroglobulinemia.