An Overview of Myelodysplastic Syndrome

A comprehensive overview of myelodysplastic syndrome, including considerations for its prevalence and the importance of early detection.

Transcript:

Amer Zeidan, MBBS, MHS: Myelodysplastic syndromes [MDS] have, for a long time, been a disease entity that’s difficult to understand. There are misconceptions out there about myelodysplastic syndromes that are important to clarify from the get-go. One of them is that myelodysplastic syndromes are not a form of cancer. Many patients come to us without having heard the word cancer before, even when they have the more advanced forms of high-risk myelodysplastic syndromes. They get very surprised and sometimes overwhelmed when they hear that this is a cancer, but we have several studies over the last 15 to 20 years that show us that MDS is definitely a form of cancer. However, like other cancers, it could be on the more aggressive or less aggressive spectrum depending on several risk stratification schema that we would be talking about.

The second thing is that, even though MDS is a cancer, it doesn’t typically present with very prolific disease like leukemia with a very high white blood cell count. It usually comes in the form of what we call a bone marrow failure. The blood counts are generally low, and the main problem is that the patients generally have complications or manifestations of low blood counts, such as infections from the low neutrophils leading to problems form the low platelets, and anemia and its complications from low hemoglobin. This is how MDS presents. A misconception is that most patients with myelodysplastic syndromes die from acute leukemia. That’s a misperception; only around one-third of patients with MDS progress to acute leukemia. However, most patients with MDS will die from MDS, not with MDS; it’s a disease that unfortunately kills many patients, and this is why it should be recognized and treated very aggressively.

Myelodysplastic syndromes are diseases of older patients. The median age in the United States is 76 years old, meaning that most of your patients are going to be in their eighth decade of life, and that imposes certain problems in terms of how aggressive treatment can be, and it makes use of bone marrow transplantation very challenging in most patients. Bone marrow transplantation is the only effective way to try to cure myelodysplastic syndromes, so what this effectively translates to is that most patients with myelodysplastic syndromes are being treated more or less with noncurative paradigms.

Bart Scott, MD, MS: In regard to prevalence for MDS, it’s important to review the difference between prevalence and incidence, because when most people consider prevalence, they mean incidence. Prevalence is used by epidemiologists to describe the overall burden of a disease, so it would include both newly diagnosed patients and patients who are already diagnosed and being treated. It could include long-term survivors of MDS, for instance.

What most people are interested in is incidence, and incidence is the number of new cases over a given time period. If you look at the most recent SEER [Surveillance, Epidemiology, and End Results Program] Registry data, the incidence per year for MDS is 4.9 per 100,000 people. The interesting thing about MDS is there is a close association between increasing age and increasing incidence. If you look, for example, for patients between ages 65 and 69, it jumps to 13.9 per 100,000 people. If you look at people over age 85, it jumps to 64 per 100,000 people. There is an increasing incidence with age, and there’s a difference between prevalence and incidence. Incidence describes new diagnosis. Prevalence is both newly diagnosed and patients who have been previously diagnosed.

It is important to know that patients have MDS, and we’d like to do a better job of diagnosing them earlier. There have been studies, patient-based internet surveys, looking at when patients were initially found to have a blood count abnormality and when they were diagnosed with MDS. On average, the patients reported that there is a 6-year delay between the initial finding of them having an abnormal blood count finding and being diagnosed with MDS.

Diagnosis at an earlier time point can be critical because there are some patients who can potentially be cured with allogeneic transplantation. Identifying those patients at an earlier time period could lead to improved outcomes. For those patients who do not have cure as an option, diagnosing them earlier could mean an earlier time to start treatment and not as much time where they have symptoms that are affecting their quality of life.