Abstract
Background
Amyloid light-chain amyloidosis (AL amyloidosis) is commonly associated with multiple myeloma. However, the clinical characteristics and prognosis of multiple myeloma with AL amyloidosis are not particularly clear.
Methods
Patients with multiple myeloma in the Peking University First Hospital registry from 2010 to 2018 were studied. The clinical and laboratory information were collected from first presentation to death or until the last available clinical follow-up. The patients’ survival and outcomes were analyzed, and the relationships between the clinical parameters and survival were also assessed.
Results
Compared with patients without AL amyloidosis, patients with AL amyloidosis had higher incidence of BNP ≧ 1000 pg/ml (P = 0.001), ALP > 187.5 IU/L (P = 0.002) and ALB < 35 g/L (P = 0.001), but lower incidence of HB < 85 g/L (P = 0.031), hypercalcemia > 2.65 mmol/L (P = 0.008), bone destruction more than three (P < 0.001), bone marrow plasma cell ratio ≧ 30% (P < 0.001) and worse D-S stage (P < 0.001). Multiple myeloma was more often complicated by λ-type AL amyloidosis than κ-type AL amyloidosis. However, further comparison found that multiple myeloma with κ-type AL amyloidosis had higher incidence of ALP > 187.5 IU/L (P = 0.001) and renal insufficiency (P = 0.001) along with worse D-S stage (P = 0.003) than multiple myeloma with λ-type AL amyloidosis. Renal biopsies of many patients suggested AL amyloidosis, but their bone marrow biopsies or subcutaneous abdominal fat pad aspirates results were negative. The existence of AL amyloidosis especially the heart involvement was related to shorter long-term survival of multiple myeloma according to univariate analysis. Cox regression model for overall survival detected the presence of AL amyloidosis in multiple myeloma having independent prognostic significance (RR = 4.52, P = 0.049).
Conclusions
Patients with multiple myeloma accompanied by AL amyloidosis have milder target organ damage and lower tumor burden. The incidence of AL amyloidosis in κ-type multiple myeloma is lower but more severe than λ-type multiple myeloma. Renal biopsy can help to identify patients with AL amyloidosis. AL amyloidosis is an independent poor prognostic factor for multiple myeloma is mainly because involvements of important organs especially the heart.
Prevalence and clinical implications of t(11;14) in patients with amyloid light-chain amyloidosis with or without concurrent multiple myeloma
