Nonparametric Prediction of Free-light Chain Generation in Multiple Myeloma Patients

Multiple Myeloma is a plasma cell cancer that produces excess Free Light Chains (FLC). Patients with this condition are treated with dialysis and chemotherapy. A previous compartmental model developed by Evans et al. [2006] described the removal of FLC through a hemodialysis membrane. In this model all rate constants were considered linear and the production of FLC a constant input function. It is known that the system rate constants and inputs are non-linear in nature due to the membrane dynamics and the use of chemotherapy to retard the production FLC producing cells. This study describes the use of maximum entropy deconvolution, in conjunction with a non-linear compartmental model, to recreate the FLC production rate in a non-parametric form, without the need for assumptions that are not supported by available data. Input functions are reconstructed from four different patients with a range of dialysis durations and FLC plasma concentrations to investigate the possible effects of chemotherapy on the underlying FLC production.