Hepatic AL Amyloidosis without Significant Light Chain Elevation in a Patient Treated with CyBorD Plus Daratumumab.

BACKGROUND Immunoglobulin light chain (AL) amyloidosis is a plasma cell disorder in which excess light chain deposits in tissues, resulting in organ dysfunction and damage. Typically, AL amyloidosis presents as a systemic disease affecting multiple organs, and most patients have elevated serum free light chains. However, the presentation of AL amyloidosis is highly variable. The purpose of this case report is to raise awareness of the atypical presentations of AL amyloidosis in order to facilitate more rapid diagnosis, which has the potential to prevent additional organ damage when appropriate therapy is provided. CASE REPORT We describe a case of AL amyloidosis with amyloid deposition confined to the liver and bone marrow and lack of significant serum light chain elevation. The patient initially presented with a spontaneous hepatic hematoma, and was ultimately found to have hepatic AL amyloidosis, with monoclonal plasma cells in the bone marrow and monoclonal protein on serum protein electrophoresis. Our patient responded to treatment with cyclophosphamide-bortezomib-dexamethasone, the anti-CD38 antibody daratumumab, and autologous stem cell transplant, resulting in hematological and organ response. CONCLUSIONS AL amyloidosis can present with end-organ damage confined to isolated organs, and it can present without the expected elevation in serum light chains. Such patients can benefit from appropriate treatment, including traditional chemotherapy, daratumumab, and stem cell transplant. As effective treatments for AL amyloidosis are now available, prompt diagnosis has the potential to limit end-organ damage and potentially improve patient outcomes.