A European collaborative study of treatment outcomes in 346 patients with cardiac stage III AL amyloidosis.

Treatment outcomes of patients with cardiac stage III light chain (AL) amyloidosis remain poorly studied. Such cases have been excluded from most clinical studies due to perceived dismal prognosis. We report treatment outcomes of 346 patients with stage III AL amyloidosis from the United Kingdom, Italy, Germany, and Greece. Median overall survival (OS) was 7 months with OS at 3, 6, 12, and 24 months of 73\%, 55\%, 46\%, and 29\%, respectively; 42\% died before first response evaluation. On an intention-to-treat basis, the overall hematologic response rate was 33\%, including a complete response rate of 12\%. OS rates at 12 and 24 months, respectively, for 201 response evaluable patients were 88\% and 85\% for complete responders, 74\% and 53\% for partial responders, and 39\% and 22\% for nonresponders. Forty-five percent of responders achieved an organ response. Amino-terminal fragment of brain-type natriuretic peptide (NT-proBNP) >8500 ng/L and systolic blood pressure (SBP) <100 mm Hg were the only factors that independently impacted OS and identified an especially poor prognosis subgroup of patients with a median OS of only 3 months. Outcome and organ function of stage III AL amyloidosis without very elevated NT-proBNP and low SBP is improved by a very good hematologic response to chemotherapy.