BUFFALO, N.Y. -- Chemotherapy given to young cancer patients does not appear to increase the risk of cancer in their offspring, the first large study of children of survivors of pediatric cancer has shown.
Results of the study, conducted by researchers at the University at Buffalo and Roswell Park Cancer Institute, appear in the most recent issue of Archives of Pediatrics & Adolescent Medicine.
"This study is important because we don't know whether therapy we give these patients will affect their children," said Daniel M. Green, M.D., professor of pediatrics at UB and Roswell Park and the study's primary author.
Green said that, to his knowledge, this study involved the largest number of fertile survivors of childhood cancer who had received chemotherapy to date. "There is essentially no data so far," he said. "This is one of the few studies to look at pregnancy outcomes. These agents are mutagenic and it was possible they could produce injury to chromosomes in germ cells that would result in congenital anomalies or cancer in their offspring. This doesn't appear to be the case."
The study involved a cohort of 405 successively treated patients who were diagnosed with cancer at Roswell Park between Jan. 1, 1960 and Dec. 31, 1989, and were 18 years of age or older at the most recent follow-up visit.
Within this group, 148 patients reported that they, their spouse or female companion had become pregnant at least once since completing cancer treatment. Ninety-one of these patients had received chemotherapy and had produced a total of 153 children.
Analysis of the health records of the children of the chemotherapy patients showed that none of the offspring had developed cancer. The frequency of birth defects, or congenital anomalies, was slightly less than for the general population -- 3.3 percent versus 3.5 percent.
There was no difference in frequency of birth defects among children of female patients and children born to spouses or female companions of male patients. Nor was there any relationship between anomalies and the patient's age at cancer diagnosis or the amount of time elapsed since completion of treatment.
Green said that while the results of the study are promising, the number of offspring is still small and most of them are still younger than their parents were when they were diagnosed with cancer. He said the sample also is too small to determine if the parents may have transmitted a mutation in a cancer-predisposition gene that caused their own cancer, or if they may have transmitted a new mutation in a cancer-predisposition gene induced by their own treatment.
The researchers will continue to follow this population of patients and offspring to search for more definitive answers.
Also participating in the research were Albert Fiorello, M.D., and Michael A. Zevon, Ph.D., of UB, and Brenda Hall and Nina Seigelstein, M.D., of Roswell Park Cancer Institute. The research was supported in part by grants from the National Institutes of Health.