The MDS Beacon™

A recent study from Harvard Medical School in Boston has shown hematopoietic stem cell transplantation (HSCT) to be less detrimental to cognitive function compared to other therapies for chronic myelogenous leukemia (CML) or primary myelodysplastic syndromes (MDS).

A HSCT is often necessary for CML or MDS patients whose bone marrow is unable to make sufficient amounts of normal blood cells during hematopoiesis, the process of blood cell production. The bone marrow of the patient is initially destroyed by chemotherapy or radiation, and then replaced with donated healthy bone marrow. HSCT is the only possible curative therapy for either disease, but concern about cognitive side effects, such as decreased memory or attention span, can influence treatment decisions.

This study investigated the effects of different treatments on the cognitive function of CML and MDS patients. Researchers made a general assessment of the 91 CML and 15 MDS patients who participated in the study by interviewing them regarding their education, occupation, past medical and psychiatric history, medication history, intelligence quotient, as well as physical and mental health. They also measured their cognitive functions through a series of tests incorporating attention, memory, and motor speed. The first assessment was made a median of 5.6 months before patients underwent any treatment. Patients were re-evaluated after 12 months, and again after 18 months.

Forty-seven percent of CML patients and 20 percent of MDS patients received HCST. The remaining 53 percent of CML patients received Gleevec (imatinib mesylate), hydroxyurea, or interferon, while 80 percent of MDS patients received hydroxyurea, supportive care, erythropoietin, or Vidaza (azacitidine).

Results showed that the improvement of cognitive function differed according to the length of time from treatment, the disease, and the type of treatment. All patients showed significant improvement in memory in the assessments after 12 and 18 months. In general, CML patients performed in the tests better than MDS patients in all neurocognitive measures. In addition, HSCT recipients improved in almost every cognitive function relative to patients with other treatments, except for physical function or motor speed. The comparatively poor physical performance may have been caused by the effects of total body irradiation and chemotherapy, graft-versus-host disease (a condition that occurs when the body’s immune system begins to attack transplanted stem cells), or medications for the treatment of graft-versus-host disease.

The study indicates that undergoing a transplant leads to the least amount of cognitive difficulty compared to other available treatment options, which is reassuring to potential HSCT recipients. However, researchers also caution that treatment side effects differ according to patient diagnosis and timing of evaluation. This is especially important because perceived mental status side effects may have been present before beginning treatment.

For more information, please see the study in the journal Cancer (abstract).