Blood Cancer Strikes Nearly Five Times More Americans Than Previously Thought

Myelodysplastic syndromes (MDS), a group of serious blood cancers, are nearly five times more common in seniors than previously thought, according to a new study by researchers from the John Theurer Cancer Center at Hackensack University Medical Center. The study also showed for the first time that MDS patients are at much higher risk for heart attack, diabetes, and other serious complications than other seniors, and that their healthcare costs are far higher. The study is published online in the Journal of Clinical Oncology.

"This study demonstrates that MDS is a very common blood cancer of the elderly, and that those who have it are at high risk of dying prematurely from other causes," says lead author Stuart L. Goldberg, MD, a hematologist/oncologist who is chief of the division of leukemia in the John Theurer Cancer Center. "This has implications for how the disease is treated and will hopefully spur additional research."

To conduct a "head-to-head" study, Goldberg and colleagues analyzed claims data for Medicare beneficiaries aged 65 and above for 2003. What they found was alarming: an estimated 45,000 new cases of MDS.

The gap in estimates can be explained by differing data sources: Medicare data are submitted by both physicians in private practice as well as hospital-based physicians, while SEER data come strictly from tumor registries, which are primarily found in hospitals.

"MDS is generally treated by hematologists and primary care physicians in private practice, and elderly patients with MDS are frequently not seen at a hospital-based cancer center until their disease progresses," says Goldberg. "So most cases are not being reported to NCI. As we found in our study, many apparently die of other causes as their disease progresses."

The researchers found a much higher incidence of other serious illnesses among MDS patients than among American seniors as a whole. More than 73% of MDS patients experienced a heart attack within three years of diagnosis, while 54.5% of the general Medicare population did. The prevalence of other conditions was also higher, including: diabetes (40% for MDS patients, vs. 33.1% non-MDS); dyspnea, a type of shortness of breath (49.4% vs. 28.5%); liver disease (.8% vs. .2%); and sepsis, a serious blood infection (22.5% vs. 6.1%). MDS patients requiring blood transfusions had a higher incidence of these conditions than those who were not transfused.

A much higher percentage of MDS patients died during the study period than those without MDS. The three-year survival rate for those with MDS was 60%, while it was 84.7% for the general Medicare population. The mortality rate for transfused MDS patients was higher than for those not transfused. The higher survival rates in this study compared to SEER were attributed to the higher percentage of early stage patients treated in communities compared to hospital-based tumor registries.

Source: John Theurer Cancer Center