Change of CD20 Expression in Diffuse Large B-Cell Lymphoma Treated with Rituximab, an Anti-CD20 Monoclonal Antibody: A Study of the Osaka Lymphoma Study Group

Change of CD20 expression was examined in cases of diffuse large B-cell lymphoma (DLBCL). CD20 expression after treatment with anti-CD20 antibody (rituximab, Rx) for DLBCL was examined in 23 cases who received serial biopsy by immunohistochemistry (IHC) and flow cytometry (FCM). CD20– by IHC and/or FCM was defined as CD20–. Four cases were CD20– at initial biopsy but became CD20+ after chemotherapy with Rx (CH-R) (group A). Recurrent tumors in three group A cases became resistant to CH-R. Initial and recurrent tumors were CD20+ before and after CH-R in 17 cases (group B). Tumors before CH-R were CD20– in two cases (group C) and continued to be CD20– in one and turned CD20+ in the other with survival time after the relapse of 8 and 23 months, respectively. Evaluation of CD20 expression with immunohistochemical and flow cytometric methods is used for the prediction of responsiveness of relapsed DLBCL for CH-R

〈Originals〉Antimicrobials for the treatment of febrile neutropenia clinical usefulness of antimicrobial cycling

[Abstract]　Bacterial or fungal sepsis is one of the leading causes of death in patients with hematological disease. Neutropenia occurs depending on the dose of chemotherapy or radiotherapy and is considered to be an important predictive factor for the incidence and severity of infection in chemotherapy patients. Approximately 40％ to 60％ of febrile patients who receive chemotherapy are clinically or microbiologically diagnosed with infection, while the remaining patients are diagnosed with fever of unknown origin and treated as such. Along with the routine use of carbapenem antibiotics (which mainly target Gram-negative bacteria) in recent years, multidrug-resistant bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), have evolved and have become a serious clinical and social problem, however, no specific strategy for infection control has yet been established. For patients with hematological disease who had fever caused by an unknown pathogen, including febrile neutropenic patients, we performed antimicrobial cycling and assessed changes over time in the isolation rates of MRSA, Pseudomonas aeruginosa, etc. For 448 patients admitted to our hospital, the use of carbapenem, penicillin, fluoroquinolone, and cephem antibiotics (all of which were injectable preparations) was rotated in this order at 3-month intervals over a two-year period (antimicrobial cycling). We concluded that cycling of the four classes of antibiotics used in this study was effective in patients with fever of unknown origin, including febrile neutropenic (FN) patients, since it could decrease the isolation rates of MRSA and P. aeruginosa