Primary systemic light chain (AL) amyloidosis occurs when plasma cells in bone marrow produce proteins that misfold and deposit in tissues, leading to organ failure and death. Between 1,200 and 3,200 new cases are reported each year in the US, although researchers believe the disease is highly under-diagnosed.
The researchers from the stem cell transplant program and the amyloid treatment and research program at Boston University Medical Center reviewed the records of 80 patients who received high-dose chemotherapy and blood stem cell transplantation from July 1994 through July 1997. The median survival for all 80 patients was 57 months.
Of these patients, 18(23%) are still alive today, 10 or more years after undergoing the treatment. By comparison, only 2% of patients treated with oral melphalan and prednisone have survived more than 10 years.
According to lead researcher, Vaishali Sanchorawala, clinical director of the stem cell transplant program, high-dose intravenous melphalan and autologous stem cell transplantation has become a first-line treatment for patients with AL amyloidosis. “However, efforts need to continue to be directed upon achieving a complete hematologic response in patients. We are finding that the proportion of patients who ultimately achieve a complete response have the highest rate of long-term survival.”