EuroFlow-Based Next-Generation Flow Cytometry for Detection of Circulating Tumor Cells and Minimal Residual Disease in Multiple Myeloma

Here, we describe the detailed protocol for minimal residual disease (MRD) assessment as well as circulating tumor cell (CTC) detection in patients with plasma cell disorders using the next-generation flow (NGF) method developed by EuroFlow. This includes the previous setup of flow cytometers, preparation and staining of samples, cell acquisition, quality control of instruments, methods and samples, as well as data interpretation to monitor MRD and CTCs with great sensitivity. It should be noted that the NGF method fully described below can be equally applied to monitor MRD in patients with systemic light-chain amyloidosis and to detect occult bone marrow involvement in patients with solitary plasmocytoma.