In a small study of 16 patients with renal amyloidosis, the 5 patients with AH amyloidosis and the 11 patients with AHL amyloidosis had less frequent concurrent cardiac involvement and better overall survival than 202 patients with renal AL amyloidosis. The hematological response to chemotherapy of the AH and AHL renal amyloidosis patients was comparable to those with renal AL amyloidosis. POEMS syndrome
POEMS syndrome (also known as Crow–Fukase syndrome, Takatsuki disease, or PEP syndrome) is a rare and complex medical syndrome that involves a combination of syndrome-defining signs and symptoms due to the dysfunction of multiple organs. The syndrome is associated with a plasma cell dyscrasia in almost 100% of cases, pathological overexpression of certain cytokines in >95% of cases, and the lymphoproliferative disorder termed Castlemans disease in ~15% of cases. (Rare cases of POEMS have been associated with polyclonal rather than clonal plasma cells; these cases are not plasma cell dyscrasias but rather appear to be caused by the over-activity of non-malignant immune cell responses in chronic infections or autoimmune diseases.) POEMS is an acronym standing for the characteristic signs or symptoms of the syndrome: Polyneuropathy, Organomegaly, Endocrinopathy, Plasma cell disorder (typically, the plasma cell burden is low in POEMS patients), and Skin changes (e.g. hemangioma, hyperpigmentation).
Genetic mutations thought to be involved in the development and/or progression of the latter disease include the L265P mutation in the MYD88 gene found in >90% of Waldenström macroglobulinaemia patients as well as various mutations in the CXCR gene found in 27% to 40% of Waldenström macroglobulinaemia patients.The clonal plasma cells involved in plasma cell dyscrasias exhibit a high degree of genetic instability. For example, the clonal plasma cell population formed by initial genetic alterations that lead to multiple myeloma contains cells that develop further genetic changes that enhance their survival, proliferation, tissue-injuring, and metastatic capacities. This allows the new cell clones to crowd out older cell clones and thereby  establish a more malignant disease. Repetition of such genetic changes underlie the evolution of a clinically silent plasma cell dyscrasia to an overt malignancy. The progressive genetic changes in clonal plasma cells include accumulating numerous single nucleotide polymorphisms, increases and decreases in gene and chromosome copy numbers, and chromosomal translocations. Genes affected include those regulating genome stability itself (e.g. KIF2B) as well as cellular activation, proliferation, and apoptosis (e.g. CIDEC, TP52, ATM, KRAS, NRAS, Wnt, and NF-κB).