Absence of p53 deletions in bone marrow plasma cells of patients with monoclonal gammopathy of undedetermined significance

We have recently shown that presence of a p53 deletion in multiple myleoma is an independent predictor for short survival. We therefore investigated w hether or not this chromosomal abnormality can be identified in patients wi th monoclonal gammopathy of undetermined significance (MGUS), Using a tripl e staining method combining staining for cytoplasmic immunoglobulins and fl uorescence in situ hybridization (FISH) with chromosome 17-centromere and p 53-gene specific probes, we studied plasma cells from 15 patients with MGUS . In all patients, concordant signal numbers with both probes were obtained (including one patient with trisomy 17), indicating that allelic loss of p 53 does not occur in MGUS.