Prognostic significance of circulating plasma cells by multi-parametric flow cytometry in light chain amyloidosis LEUKEMIA Sidana, S., Tandon, N., Dispenzieri, A., Gertz, M. A., Dingli, D., Jevremovic, D., Morice, W. G., Kapoor, P., Kourelis, T. V., Lacy, M. Q., Hayman, S. R., Buadi, F. K., Leung, N., Go, R. S., Lin, Y., Russell, S. J., Lust, J. A., Zeldenrust, S. R., Warsame, R., Hwa, Y. L., Hobbs, M., Fonder, A., Kyle, R. A., Rajkumar, S., Kumar, S. K., Gonsalves, W. I. 2018; 32 (6): 1421–26

Abstract

We evaluated the prognostic impact of clonal circulating plasma cells (cPCs) detected by six-color multi-parametric flow cytometry (MFC) in light chain (AL) amyloidosis at diagnosis. Of the 154 patients who underwent MFC, cPCs were detected in 42% (n?=?65) patients. Median number of cPCs was 81 per 150,000 events (range: 6-17,844). High bone marrow plasma cell percentage was an independent predictor of presence of cPCs. Presence of cPCs at diagnosis was associated with inferior overall survival (OS) (90 vs. 98 months, p?=?0.003) and inferior progression free survival (PFS) (31 vs. 52 months, p?=?0.02). Estimated 1, 2 and 5 year OS in the two groups was: 74, 64 and 57 and 89, 87, and 80%, respectively. Estimated PFS at 1, 2, and 5 years was: 69, 56, and 23% and 80, 74, and 37%, respectively. Furthermore, the presence of cPCs at diagnosis was an independent adverse predictor of OS in multivariable analysis. Achieving a very-good partial response, or better, was able to overcome the adverse impact of cPCs at diagnosis. Patients with cPCs at diagnosis may warrant closer monitoring post-treatment, especially if they do not achieve a deep hematologic response.

View details for DOI 10.1038/s41375-018-0063-7

View details for Web of Science ID 000434474100015

View details for PubMedID 29483709

View details for PubMedCentralID PMC5992020