Anti-CD5 monoclonal antibody, clone CC17 [FITC]

Background The CLLflow score was recently suggested as an improvement over the Moreau score (MS) for the diagnosis and classification of B-cell lymphoproliferative disorders (B-LPD). Methods We determined the CLLflow score in peripheral blood or bone marrow of a series of cases with an inconclusive immunophenotype, including samples with a MS of 3 (n = 52) and CD5-positive with a score of 2 (n = 38). As controls, B-LPD with a MS of 0-1 (n = 95), CD5-negative score 2 (n = 24), and score 4-5 (i.e., chronic lymphocytic leukemia [CLL], n = 166) were included. Results The CLLflow score was positive (suggestive of CLL) in all CLL cases and negative in all MS <2, regardless of CD200-positivity, which occurred in 31% (29/95) of cases. The CLLflow score was positive in 71%, 29%, and 8% of samples with a MS 3, CD5-positive score 2, and CD5-negative score 2, respectively. Discussion Our results suggest that the CLLflow is useful in the differential diagnosis of cases with inconclusive immunophenotype. (c) 2018 International Clinical Cytometry Society

A 58-year-old Japanese woman complained of a painful right maxillary premolar gingiva and ulcer. The patient had RA and had been treated with several immunosuppressive drugs such as methotrexate. Head and neck CT indicated no obvious bone destruction with maxillary. However, chest CT indicated the presence of nodular mass of the bilateral lungs. FDG-PET/CT indicated the presence of increased uptake in both lesions. On immunohistochemistry, atypical large-sized lymphocytes were positive for CD20 and EBER-ISH and negative for CD3, CD5, and CD10; the Ki-67 labeling index was high, the histopathological diagnosis was EBV-positive DLBCL, and the clinical diagnosis was MTX-LPD. The patient's treatment with MTX was then discontinued; we removed the alveolar bone which necrosed after 5 weeks. The lesion and the nodular mass at the bilateral lungs had completely disappeared after 7 weeks.