Search

Systemic AL amyloidosis (AL) is a disorder in which light chains form fibrillar deposits, leading to organ dysfunction and death. Rarely, AL has been associated with non-Hodgkin's lymphoma (NHL), although this association has not been well characterized. We report a series of six patients with AL associated with NHL, primarily lymphoplasmacytic lymphoma. Organ involvement was variable, with frequent bulky lymphadenopathy and visceral cavity deposits, but no cardiac involvement. Positron emission tomography scans were negative. Bone marrow and lymph node biopsies showed a mixed population of CD20+ lymphoid and CD138+ plasma cells. Serum free light chains were elevated, and correlated with response to therapy. Immunoglobulin light chain variable region (Ig VL) germline gene use was typical for AL, reflecting previously observed correlations between germline gene use and organ tropism. Five patients received rituximab-based therapies with two responses. Two patients underwent autologous stem cell transplantation with one complete haematological response. Four patients survive at 10–132 months from diagnosis. AL with NHL has distinctive clinical features but employs the same Ig VL gene repertoire as AL with clonal plasma cell dyscrasias. Serial serum free light chain levels are useful for tracking response to therapy. Treatments aimed at both lymphoid and plasma cell components appear warranted. [ABSTRACT FROM AUTHOR]

The net impact of malignancy and anti-tumor therapy on bone resorption in myeloma is poorly understood because conventional skeletal radiographs are relatively insensitive for the diagnosis and monitoring of bone disease. We performed determinations of bone mineral density (BMD) at the lumbar spine, femoral neck and radial diaphysis by dual energy X ray absorptiometry (DEXA) in 168 consecutive patients with myeloma seen at our institution. Follow up studies were performed in 41 of these patients. A detailed analysis of patient and disease characteristics was performed to identify the determinants of BMD. Compared to normal age and sex matched controls, mean (± SE) BMD was significantly decreased at the lumbar spine (Z score −0.4 ± 0.10) and femoral neck (Z score −1.0 ± 0, 10), but was surprisingly above normal at the radial diaphysis (Z score + 0.35 ± 0.10), a cortical bone site devoid of hematopoietic marrow, suggesting a differential bone preserving effect at this site. Lack of correlation between the BMD findings and the presence or extent of radiographically evident osteolytic lesions suggested the presence of a systemic bone disease. On multivariate analysis, duration of disease >12 months (p = 0.003) and female sex (p = 0.01) were independently associated with a lower BMD at the femoral neck/lumbar spine. On follow up DEXA (n = 41), BMD increased at ≥ 1 site in 9 of 20 patients receiving bisphosphonates and in only 2 of 21 patients not receiving such therapy (p = 0.02). Similarly a decline in BMD at ≥ 1 site was seen in 9 of 21 patients not receiving bisphosphonates, irrespective of the disease response status. Interval pamidronate therapy (p = 0.0007) and a low serum beta-2-microglobulin (< 2.5 mg/l) (p = 0.04) were the two most significant variables associated with an increase in BMD on multivariate analysis. These data suggest that myeloma is associated with a systemic bone disease with progressive... [ABSTRACT FROM AUTHOR]