Light chain deposition disease: pathogenesis, clinical characteristics and treatment strategies

Light chain deposition disease (LCDD) is a rare hematologic disorder characterized by the deposition of non-amyloid monoclonal light chains in several organs. Together with renal impairment is being the primary morbidity associated with this disease. Due to its rarity, randomized clinical trials lack to explore treatment strategies and there are no approved or universally accepted standard of care treatment options. We aimed to provide a systematic summary of histological and clinical aspects of LCDD and treatment options of available literature therapies strategies. Currently, drugs used to treat multiple myeloma are recommended when LCDD patients also presented multiple myeloma. Anyway, in patients with LCDD that is not associated to multiple myeloma, haematopoietic stem cell transplantation (ASCT) and chemotherapy with thalidomide, dexamethasone, bortezomib are also recommended. In eligible patients, bortezomib-based chemotherapy followed by ASCT appears to be an effective treatment option with durable hematologic remission and organ responses. Although it appears that the patients undergoing ASCT seem to achieve deeper and durable hematologic remissions and organ responses, no statistically significant superiority can be demonstrated over non-transplant or standard chemotherapy-based approaches. As retrieved by our review, bortezomib-based therapy appears to be favorable strategy as long as no dose modification is required for renal impairment, and early hematologic responses as a recovery of renal function. Encouraging data were also demonstrated by treatment lenalidomide or melpalan based. Moreover, new myeloma treatment strategies, as monoclonal antibody Daratumumab, seem to be effective in LCDD. Instead, renal allograft is not recommended, due to high incidence of relapse.