The study aims to include 20 patients with multiple myeloma that are initiating bortezomib treatment. The patients must follow their normal treatment cycles while getting blood drawn during their treatment period however maximal 9 cycles.~Blood is dawn before treatment initiation and approximately once per cycle in order to measure neurofilament light chain (NFL) before and during treatment. The primary outcome is to relate the level of NFL during treatment with the level at baseline and as a secondary outcome to relate the level of NFL to the cumulative dose of bortezomib.
Investigation of which patients treated with bortezomib that have increased risk of developing peripheral neuropathy.