Mott cells in CD20-positive myeloma

Immunohistochemical evaluation of CD20 expression in patients with multiple myeloma

OBJECTIVE CD20 expression was reported at different rates in patients with multiple myeloma. The importance of this B-cell antigen for plasma cells is still unknown. This study aimed to investigate CD20 expression of myeloma cells in bone marrow, and any relationship between the stage of disease, isotype and clinical features. METHODS Sixty-one patients who were admitted to the hematology cli...

[A case of CD20 positive mediastinal rhabdomyosarcoma].

We present the case of a 16-year-old boy admitted with a large mediastinal mass. Both in the mediastinal tru-cut biopsy and the bone marrow biopsy, a malignant small round cell tumor was determined. The clinical diagnosis was leukemia or lymphoma. The cytoplasmic CD20 expression was shown on the tumor cells of the mediastinal tru-cut biopsy. Rhabdomyosarcoma was diagnosed by the...

Amyloid arthropathy associated with multiple myeloma: polyarthritis without synovial infiltration of CD20+ or CD38+ cells

OBJECTIVES To describe histological, immunohistochemical and ultrastructural features of synovial biopsies of amyloid arthropathy associated with multiple myeloma (MM). METHODS Synovial biopsies from affected joints of two patients with MM and amyloid arthropathy were examined with light and electron microscopy, and immunohistochemically for expression of CD3, CD8, CD20, CD38, CD68, Ki-67 and...

Accelerated progression of multiple myeloma during anti-CD20 (Rituximab) therapy.

CD20 positive cells are undetectable in the majority of multiple myeloma cell lines and are not associated with a cancer stem cell phenotype.

Although new therapies have doubled the survival of multiple myeloma patients, this remains an incurable disease. It has been postulated that the so-called myeloma cancer stem cells would be responsible for tumor initiation and relapse but their unequivocal identification remains unclear. Here, we investigated in a panel of myeloma cell lines the presence of CD20(+) cells harboring a stem-cell ...