© 1999 Atlas of Genetics and Cytogenetics in Oncology and Haematology Clinics and pathology Disease

Multiple myeloma (MM) is a malignant plasma cell proliferation Phenotype/cell stem origin Mature differentiated B-cell, but also with CD56 expression, which is not found in normal plasma cell; CD38+, CD40+, CD138+. Epidemiology MM's annual incidence is 30/106; del(6q) is observed in about 2 to 5 % of MM cases (i.e.: 5-10 % of cases with an abnormal karyotype). Clinics Bone pain; susceptibility to infections; renal failure; neurologic dysfunctions. Pathology MM staging:- stage I: low tumour cell mass; normal Hb; low serum calcium; no bone lesion; low monoclonal Ig rate;- stage II: fitting neither stage I nor stage II;- stage III: high tumour cell mass; low Hb and/or high serum calcium and/or advanced lytic bone lesions and/or high monoclonal Ig rate