People treated for cancer when they were children have a higher-than-average risk of gastrointestinal problems – some mild, some quite severe – in the years following treatment, according to a study to be presented at the 42nd Congress of the International Society of Paediatric Oncology (SIOP) in Boston on Sunday, Oct. 24.

Investigators at Dana-Farber/Children's Hospital Cancer Center and their colleagues say their findings suggest that childhood cancer survivors and their physicians should be especially aware of the increased likelihood of gastrointestinal troubles and factor them into plans for monitoring survivors' health.

"Current treatments have dramatically increased survival rates for children with cancer, but we know that many cancer therapies – including surgery, radiation, and chemotherapy – can cause significant gastrointestinal (GI) complications for patients," says the study's senior author, Lisa Diller, MD, director of the Perini Family Survivors Center at Dana-Farber.

"Little is known, however, about the long-term GI consequences for childhood cancer survivors."

To identify such delayed effects, researchers searched for instances of upper GI (esophageal, stomach) problems, liver disorders, and lower GI (intestinal) problems in 14,358 participants in the Childhood Cancer Survivor Study, which tracks the health of children diagnosed with cancer between 1970 and 1986 who survived at least five years after treatment.

Rates of GI disorders in these survivors were compared to rates in a randomly selected group of their siblings.

Most of the survivors had received chemotherapy, and about a third had received radiation and/or chemotherapy.

Researchers found that the survivors had an elevated risk for upper GI complications such as ulcers, indigestion, heartburn, esophagus problems, nausea, and vomiting; for liver conditions such as cirrhosis, gallstones, and jaundice (and were 24 percent more likely than siblings to have needed a liver biopsy); and for lower GI problems such as colitis, constipation, diarrhea, and intestinal polyps or blockage.

In general, survivors who were diagnosed at an older age and had more intensive radiation and/or chemotherapy and more extensive surgery had higher rates of these complications.

These increased risks make it important for survivors to inform their physicians of their earlier cancer treatment, and for physicians to consider whether GI problems are symptoms of a more serious disease in these patients, Diller states.

In recent years, pediatric oncologists have worked to develop lower-dose treatments and less invasive surgical procedures to reduce the long-term consequences of childhood cancer therapy, she adds.

The study was funded by a grant from the National Cancer Institute.

The lead author of the study is Robert Goldsby, MD, of the University of California San Francisco Children's Hospital.

Co-authors are Shannon Raber, NP, and Linda Li, CRC, UCSF Children's Hospital; Yan Chen, and Yutaka Yasui, PhD, Public Health Services of the University of Alberta, in Edmonton, Canada; Karen Diefenbach, MD, and Nina Kadan-Lottick, MD, MSPH, Yale University School of Medicine, New Haven, Conn; Margarett Shnorhavorian, MD, MPH, Seattle Children's Hospital; Fay Kastrinos, MD, MPH, Columbia University Medical Center, New York; Marilyn Stovall, MPH, M.D. Anderson Cancer Center, Houston; Kevin Oeffinger, MD, and Charles Sklar, MD, Memorial Sloan-Kettering Cancer Center, New York; and Greg Armstrong, MD, MSCE, and Leslie Robison, PhD, St. Jude Children's Research Hospital, Memphis, Tenn.