The Landscape of Cytogenetic Aberrations in Light-Chain Amyloidosis with or without Coexistent Multiple Myeloma

Interphase fluorescence in situ hybridization (iFISH) has been well established in the preliminary prognostic evaluation of multiple myeloma (MM). However, the chromosomal aberrations in patients with systemic light-chain amyloidosis, notably in patients with coexistent MM, have been rarely investigated. This study aimed to evaluate the effect of iFISH aberrations on the prognosis of systemic light-chain amyloidosis (AL) with and without concurrent MM. The iFISH results and clinical characteristics of 142 patients with systemic light-chain amyloidosis were analyzed, and survival analysis was conducted. Among the 142 patients, 80 patients had AL amyloidosis alone, and the other 62 patients had concurrent MM. The incidence rate of 13q deletion, t(4;14), was higher in AL amyloidosis patients with concurrent MM than that of primary AL amyloidosis patients (27.4% vs. 12.5%, and 12.9% vs. 5.0%, respectively), and the incidence rate of t(11;14) in primary AL amyloidosis patients was higher than that in AL amyloidosis patients with concurrent MM (15.0% vs. 9.7%). Moreover, the two groups had the similar incidence rates of 1q21 gain (53.8% and 56.5%, respectively). The result of the survival analysis suggested that patients with t(11;14) and 1q21 gain had a shorter median overall survival (OS) and progression-free survival (PFS), irrespective of the presence or absence of MM, and patients with AL amyloidosis and concurrent MM carrying t(11;14) had the poorest prognosis, with a median OS time of 8.1 months.