multiple myeloma (MM) is a malignant plasma cell proliferation

mature differentiated B-cell, but also with CD56 expression, which is not found in normal plasma cell; CD38+, CD40+, CD138+.

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).

bone pain; susceptibility to infections; renal failure; neurologic dysfonctions

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

MM can evolve towards plasma cell leukemia

prognosis (highly variable) is according to the staging and other parameters, of which are now the karyotypic findings : two distinct cytogenetic pattern have been reported, according to the chromosome number : 1- a hyperdiploid pattern, and 2- a pattern of either pseudodiploidy,hypodiploidy or near-tetraploidy karyotypes; patients with the latter pattern appear to have a worse prognosis than patients with a hyperdiploid karyotype (med survival of 1.5 yr vs 3 yrs; p