Two cases of t(1;16)(p11;p11) in multiple myeloma: confirmation by chromosome painting.

Two patients with multiple myeloma and an unbalanced translocation, t(1;16)(p11;p11), are reported. The fluorescence in situ hybridization (FISH) technique was used in one patient to confirm the translocation. To our knowledge, t(1;16)(p36;q13) and t(1;16)(q21;p13), but not t(1;16)(p11;p11), had been reported previously in multiple myeloma. Our results suggest that FISH is useful to characterize structural abnormalities and identify marker chromosomes in multiple myeloma where analysis with conventional cytogenetics is often difficult.