THURSDAY, July 20, 2006 (HealthDay News) -- New research provides more evidence that certain chemotherapy drugs can harm the hearts of young people with cancer and cause worsening cardiac problems decades later.
Dutch scientists found that some adults who had undergone cancer treatment as children and young adults suffered from growing heart irregularities as they aged into their 30s and 40s.
"The take-home message is that long-term survivors of childhood cancer are a high-risk group for the development of premature symptomatic cardiovascular disease," said Dr. Steven Lipshultz, chairman of pediatrics at the University of Miami School of Medicine.
At issue are chemotherapy drugs known as anthracyclines. According to Lipshultz, the medications revolutionized childhood cancer treatment in the 1970s and helped contribute to today's high long-term survival rate -- almost 80 percent -- for kids with cancer.
But researchers have also found that survivors of childhood cancer, especially girls and black patients, become more likely to develop heart problems later on, Lipshultz said. Radiation treatment that encompasses the heart can also raise the risk of future disease.
Studies have suggested that the risk of heart disease in some long-term cancer survivors is eight times higher than in people who didn't have cancer or cancer treatment, Lipshultz said.
The Dutch researchers tracked 22 patients, averaging 39 years of age, who underwent chemotherapy as children or young adults. While the number of people was small, the study is believed to be the longest-lasting of its kind since the patients were followed for an average of 22 years.
Reporting in the July 20 online issue of the Annals of Oncology, the researchers found that 27 percent of the patients had systolic dysfunction, a condition where the heart's left chambers fail to pump effectively. And nearly half (45 percent) had diastolic dysfunction, where the left chambers of the heart aren't fully relaxed after pumping.
Both percentages rose significantly from a previous study of the patients in 1997, the researchers note. At that time, just 9 percent and 18 percent of the group had systolic and diastolic dysfunction, respectively.
It appears that the chemotherapy treatment somehow damaged cells in the muscles of the heart, said lead researcher Dr. Inge Brouwer, a pediatric oncologist with the University of Groningen in the Netherlands.
"We think that this damage to heart cells is ongoing after cessation of anthracycline treatment, but the exact mechanism that might cause these problems is not yet known," the researcher said.
What to do? Anthracyclines are considered effective in fighting childhood cancers, so doctors are now looking ways to prevent future heart disease.
According to the study, some patients are now receiving lower doses of chemotherapy drugs than in the past, and drugs to protect the heart are now available.
Former patients can also take action themselves. "Healthy lifestyle seems to be important in prevention of cardiac problems, so former patients need to be stimulated to stop smoking, take their exercise and reduce weight if necessary," Brouwer said. Treatment for high cholesterol or blood pressure may also be necessary, she said, and doctors should keep an eye out for not-so-obvious signs of potential heart problems.
More information
Find out more at the Candlelighters' Childhood Cancer Foundation.
