Bone marrow findings correlate with clinical outcome in systemic AL amyloidosis patients.
OBJECTIVE
Bone marrow sampling is a key investigation in the work-up of amyloid light chain (AL) amyloidosis, but the relationship between bone marrow findings and the varied phenotype and clinical outcome of AL amyloidosis is unclear. The aim was to determine if bone marrow pathological parameters at diagnosis were related to clinical behaviour in AL amyloidosis patients.


RESULTS
Bone marrow findings, clinical features and outcome of 80 patients referred with a diagnosis of systemic AL amyloidosis were evaluated; six patients were subsequently excluded due to re-categorization as other forms of amyloidosis. At latest follow-up (median 66 months), 11 of the 18 patients with no identifiable bone marrow neoplastic cells (61%) versus only seven of the 56 patients with neoplastic plasma cells or non-Hodgkin's lymphoma (13%) were alive (P = 0.0046). However, neither the quantity of the neoplastic cells nor the serum light chain levels were correlated with amyloid burden or patient survival.


CONCLUSIONS
Identification of a neoplastic population in the bone marrow of AL amyloidosis patients by histology and immunohistochemistry correlates with poor outcome; however, the neoplastic cell burden is not prognostically significant, suggesting that additional factors are important in determining disease behaviour in AL amyloidosis.
Hasserjian
R P
RP
James Homer-Wright Pathology Laboratory, Department of Biostatistics, Massachusetts General Hospital, Boston, MA, USA. rhasserjian@partners.org
Goodman
H J B
HJ
Lachmann
H J
HJ
Muzikansky
A
A
Hawkins
P N
PN
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000682:Amyloid / Q000276:immunology / Q000378:metabolism*; D000686:Amyloidosis / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D001853:Bone Marrow / Q000378:metabolism / Q000473:pathology*; D001854:Bone Marrow Cells / Q000378:metabolism / Q000473:pathology*; D004252:DNA Mutational Analysis; D005260:Female; D005340:Fibrinogen / Q000235:genetics / Q000378:metabolism; D005838:Genotype; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000276:immunology / Q000378:metabolism; D008228:Lymphoma, Non-Hodgkin / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D011228:Prealbumin / Q000235:genetics / Q000378:metabolism; D015996:Survival Rate; D006113:United Kingdom / Q000453:epidemiology
D000682:Amyloid; D007147:Immunoglobulin Light Chains; D011228:Prealbumin; C035222:amyloid protein AL; D005340:Fibrinogen