In a nutshell
This study examined if the numbers of different immune cells before and after a stem cell transplant (SCT) predicted treatment outcomes for patients with multiple myeloma (MM). The authors concluded that the numbers of two types of immune cells and antibody levels were associated with a successful transplant.
Some background
MM is a cancer of white blood cells (immune cells). Autologous SCT is an essential part of treatment for MM. Chemotherapy is given first to get rid of any remaining cancer cells. Then, stem cells are collected from the patient's blood. These cells are given back to the patient after treatment to help make new healthy immune cells.
Outcomes after SCT vary among patients. Some patients have cancer come back or grow soon after treatment, while others have no signs of disease for several years. As the goal of the SCT treatment is to replace immune cells, the numbers of different immune cells and antibodies may help predict long-term outcomes. Whether these markers can predict outcomes for patients with MM is unclear.
Methods & findings
130 patients with MM received melphalan (Alkeran) before undergoing SCT. Blood samples were taken from patients 2 days before and 90 days after SCT to analyze immune cell counts. The length of time before patients required more treatment is called treatment-free survival (TFS). The average TFS after SCT was 25 months.
Lymphocytes are a type of immune cell that produces antibodies. 90 days after SCT, patients with high lymphocyte counts had a significantly longer TFS than patients with low lymphocyte counts (23 months vs. 18 months).
Monocytes are a type of immune cell that kills bacteria. 90 days after SCT, patients with low monocyte counts had a longer TFS compared to patients with high monocyte counts (25 months vs. 13 months).
The lymphocyte to monocyte ratio (LMR) compares the numbers of lymphocytes to monocytes. Patients with a low LMR had a shorter TFS (16 months) than patients with a high LMR (52 months). Patients with a high LMR had a 66% lower risk of needing more treatment after SCT.
Different types of antibodies fight different kinds of infections. Patients who stopped producing 2 or 3 types of antibodies had a shorter TFS (17 months) than patients who continued to produce 1 or more types of antibodies (51 months). Patients who continued to produce 1 or more types of antibodies had a 2.66-fold longer TFS.
The bottom line
This study found that the levels of lymphocytes, monocytes, and antibodies found in the blood after SCT can help predict long-term outcomes for patients with MM. The authors suggest that identifying patients at risk of relapse may help guide further treatment.
The fine print
This study had a small number of patients. More studies are needed to confirm these results.
Published By :
Bone Marrow Transplantation
Date :
Sep 16, 2019
