Stem cell transplants are a treatment option for chronic lymphocytic leukemia (CLL) patients with harder to treat disease. Over time, the use of stem cell transplants has declined with the introduction of targeted therapies such as ibrutinib, venetoclax, and PI3K inhibitors. With all these changes, what is the role of stem cell transplants in the new landscape of CLL treatment options?
At the annual meeting of the American Society of Hematology (ASH) 2019, our own Dr. Brian Koffman interviewed Dr. Lindsey Roeker, a clinical fellow at Memorial Sloan Kettering Cancer Center. They discussed the current role of stem cell transplants in CLL.
Stem cells transplants allow doctors to use higher doses of chemotherapy (which might be damaging to the bone marrow) to treat CLL. After treatment, patients receive a transplant of blood-forming stem cells to restore their bone marrow. There are two main types of stem cell transplants:
- Allogeneic transplant – Patients receive an infusion of stem cells, which are donated from another person with a matching tissue type. This is the main type of transplant used to treat CLL.
- Autologous transplant – A patient’s own stem cells are collected from their blood or bone marrow and given back after treatment (most likely chemotherapy). This transplant is generally not used, because when the stem cells are collected leukemia cells may be collected as well.
You can find more detailed information on the different types of stem cell transplants here.
- This study looked at outcomes for 69 patients at multiple sites in the United States and European Union who underwent allogeneic stem cell transplantation after previously receiving one or more targeted therapies.
- Prior to the stem cell transplant, 78% of patients had been treated with ibrutinib; 39% had been treated with venetoclax;, 20% had been treated with a PI3K inhibitor;, and 36% had been treated with ≥ 2 targeted therapies.
- After 2 years, progression free survival was 60% and overall survival was 82%.
- Stem cell transplantation worked well regardless of mutational status, i.e. del17p or TP53 mutations.
- Things that influence how well stem cell transplantation works are how well the disease is controlled prior to transplant and any other medical problems. Healthier people tend to tolerate the transplant better.
- Some patients die because of complications from the transplant itself rather than CLL, but this number is small.
- Stem cell transplants are mainly considered for young patients, who are otherwise healthy, but who have certain features that are likely to make the disease hard to control in the long term.
There is still a role for stem cell transplants in CLL, but that role is shrinking and being redefined as new targeted therapies become available. For patients who are refractory or resistant to targeted therapies, stem cell transplants still offer a potentially curative option.
Please enjoy this brief interview with Dr. Roeker from December 2019 at ASH in Orlando, FL.
You can read the actual ASH abstract here: Allogeneic Stem Cell Transplantation (alloHSCT) for Chronic Lymphocytic Leukemia (CLL) in the Era of Novel Agents
Take care of yourself first,
Ann Liu, PhD