Hodgkin Disease Survivors Face Higher Risk For Stroke Later In Life

Principal investigator Dr. Daniel Bowers, assistantprofessor of pediatrics, and other UT Southwestern researchersidentified the link using patient information from a national databaseof long-term childhood cancer survivors. The study, which appeared inthe Journal of Clinical Oncology, is available online.

"We weresurprised. We knew there was increased risk of a second cancer -usually breast cancer - and increased risk of heart failure, but strokewas unexpected," said Dr. Bowers.

Although doctors cure about 70percent of pediatric outpatients with cancer, little research hadlinked strokes later in life to cancer. Testing that hypothesis on allsurvivors of childhood cancer was too impractical, so the UTSouthwestern research team narrowed the field to survivors of Hodgkindisease, a type of lymphoma that's the second-most common form ofchildhood cancer.

"The goals are changing to more than justcuring the child of cancer," Dr. Bowers said. "They are to evaluate andreduce the long-term side effects. It's been well-established thatchildhood cancer survivors have several well-described long-term sideeffects, including second cancers, learning problems, growth problemsand heart damage."

UT Southwestern is a member of the ChildhoodCancer Survivor Study, a national consortium tracking the long-termeffects of cancer survivors. Children's Medical Center Dallas is also amember and contributed patients to the study. The National Institutesof Health-sponsored study involves 27 institutes and the statisticalhistories of some 20,000 childhood cancer survivors.

From thatdatabase, researchers identified 1,926 people who had survived Hodgkindisease more than five years after being diagnosed between 1970 and1986. Dr. Bowers and other researchers identified 24 Hodgkin diseasesurvivors who later reported a stroke and compared that to the siblingsof cancer survivors, where only nine of more than 3,800 had sufferedstrokes. The incidence of strokes - 83.6 per 100,000 person-years forHodgkin disease survivors and 8.0 per 100,000 person-years for thecontrol group - demonstrated that Hodgkin disease survivors were atsignificantly increased risk of suffering a stroke.

"With thehigh visibility of stories like Lance Armstrong, people think that ifyou're a cancer survivor you're cured, and you have no furtherproblems, and you can go ride in the Tour de France," Dr. Bowers said."And maybe that's true for some people. But we are clearly recognizingthat cancer survivors have unique and long-term cancer-specific sideeffects. People are beginning to look at quality of life."

The UTSouthwestern research may support other studies suggesting the need toreduce the amount of radiation used in treatments for Hodgkin disease,he said.

"The next generation of studies will be able to look atthe question: Does a reduction in radiation dose cause a decrease inthe frequency of stroke?" Dr. Bowers said. "It certainly would be alogical expectation, but we don't know that."

Other researchersinvolved in the study were senior author Dr. Kevin Oeffinger, a formerfamily practice professor at UT Southwestern, now with the MemorialSloan Kettering Cancer Center, and researchers from UT M.D. AndersonCancer Center in Houston, the Food and Drug Administration, theUniversity of Minnesota, St. Jude Children's Research Hospital inMemphis, Tenn., Stanford University School of Medicine, Children'sNational Medical Center in Washington, D.C., and the Childhood CancerSurvivor Study.

The study was funded by the Department of Health and Human Services and the Children's Cancer Research Fund.