Finding smudge cell aggregations in a bone marrow smear preparation may be helpful in the diagnosis of intravascular large B-cell lymphoma

Abstract

Smudge cells are fragile cells that ruptured through the physical process of smear preparation. Smudge cells have often been observed in smear specimens of lymphoid neoplasms, particularly in cases of chronic lymphocytic leukemia. The presence of many smudge cells in a smear preparation may indicate a neoplastic disease. In a patient, the finding of smudge cell aggregation in a bone marrow smear specimen led us to suspect hematological malignancies. The patient was a 50-year-old woman who complained of high-grade fever and was admitted to our hospital. Blood examination revealed anemia, thrombocytopenia, and elevations of serum lactate dehydrogenase, C-reactive protein, ferritin, and soluble IL-2 receptor levels. Although these findings suggest hematological disorders such as malignant lymphoma, whole-body computed tomography showed no swollen lymph nodes. Bone marrow examination showed many smudge cell aggregations and large lymphoma cells. These lymphoma cells were positive for CD20. On the basis of these bone marrow findings, random skin biopsy was performed. CD20-positive lymphoma cells were observed in blood vessels of cutaneous tissues. Therefore, this patient was diagnosed as having intravascular large B-cell lymphoma (IVLBCL). Generally, early diagnosis of IVLBCL is reported to be difficult because of the lack of overt lymphadenopathy and mass formation. Smudge cell aggregations in bone marrow smear specimens may be helpful in the diagnosis of hematologic malignancies. It is possible that smudge cells may be observed in not only chronic lymphocytic leukemia but also other hematologic malignancies.