Serum Levels of Free Light Chain before and after Chemotherapy in Primary Systemic AL Amyloidosis

Abstract

Objective Immunoglobulin-related free light chains (FLCs) in serum have recently become quantitatively detectable using the nephelometric assay in plasma cell disorders, including multiple myeloma and AL amyloidosis. To investigate whether FLCs are useful as a diagnostic and therapeutic marker in Japanese patients with primary systemic AL amyloidosis, we determined these values in serum before and after chemotherapy.Patients and Methods The serum FLC analysis was carried out in 25 patients with primary systemic AL amyloidosis (mean age, 60.1±8.4 years). All of the patients were shown to have either AL -or ALimmunoreactive amyloid deposits on biopsied tissues. Thirteen patients were treated with VAD (vincristine, doxorubicin and dexamethasone) alone (n=6) or VAD and subsequent high-dose melphalan followed by autologous stem cell support (n=7), and serum FLCs were serially determined before and after the chemotherapy.Results Before chemotherapy the amyloidogenic FLC was elevated in serum with or without abnormal / ratios in 24 patients, including 5 with undetectable Mprotein in both serum and urine on immunofixation. After chemotherapy the amyloidogenic FLC in serum was significantly decreased irrespective of high-dose melphalan (p<0.05), and all the patients with normalized / ratios showed a good prognosis. Conclusions With respect to sensitivity and quantification serum FLCs will be a key marker for diagnosis and therapeutic effects in primary systemic AL amyloidosis. The prognosis of patients with this disease may be improved if the / ratio in serum can be normalized by intensive chemotherapy.

Marked and Rapid Regression of Hepatic Amyloid Deposition in a Patient with Systemic Light Chain (AL) Amyloidosis after High-dose Melphalan Therapy with Stem Cell Transplantation

“…These assessments are usually obtained from blood and urine tests (such as immunofixation tests and measurements of the BNP, FLC and ALP levels, etc.) (18) and imaging examinations, including echography and CT (6). It is possible to more easily estimate the presence of a hematologic CR if monoclonal protein is detectable before treatment (6), although the im- munofixation tests conducted in our patient were negative in both the serum and urine.…”

Trends in day 100 and 2-year survival after auto-SCT for AL amyloidosis: outcomes before and after 2006

“…The most important change was the development of the Ig free light-chain assay, which allowed a more accurate determination of hematological response. [28][29][30] Reports on the efficacy of melphalan and prednisone may underestimate the true response rates because none of the studies included light-chain measurements. 31,32 Response rates with novel agent-based therapy are extremely high and rival those seen with auto-SCT.…”

Surgical removal of amyloid-laden lymph nodes: a possible therapeutic approach in a primary systemic AL amyloidosis patient with focal lymphadenopathy

“…No abnormal findings were found on either the electrocardiogram or echocardiogram, and there was no amyloid deposition in the biopsied gastroduodenal mucosa. Quantitative assay of serum free light chains (FLCs) revealed an increase in λ-chain (48.7 mg/L, normal 5.7-26.3 mg/L) and a slight decrease in the κ/λ ratio (0.24, normal 0.26-1.65) [7]. At age 50 she received two courses of VAD (vincristine, doxorubicin and dexamethasone) and subsequent HDM/SCT [2,8] At age 52 she underwent surgical removal of the involved lymph nodes.…”