To make a cytogenetic diagnosis of myeloma cells more convenient in daily practice universally, we in this study developed a new diagnostic modality of the multiplex FISH in immunophenotyped cells in suspension (Immunophenotyped-Suspension-Multiplex (ISM)-FISH), using the imaging flow cytometry which can simultaneously examine three disease-specific chromosomal translocations, i.e., t(11;14), t(4;14) and t(14;16) in CD138-positive tumor cells of plasma cell dyscrasia, including MM and monoclonal gammopathy of undetermined significance (MGUS). This evidence concerns the gene SDC1 and plasma cell myeloma.