Last Updated: 2007-09-05 12:13:39 -0400 (Reuters Health)

By Amy Norton

NEW YORK (Reuters Health) - Teenagers who've survived childhood cancers may be more likely than their siblings to be depressed or anxious, have attention problems or show antisocial behaviors, researchers report.

Leukemia, tumors of the brain or spine, and neuroblastoma -- a cancer that arises in nerve tissue -- were all related to higher risks of emotional and behavioral problems.

The researchers do stress that despite these risks, most teenage cancer survivors seem to be "adjusting well." However, the findings suggest that they may need to be screened for problems like depression and antisocial behavior.

"Since adolescents, regardless of medical history, may face challenges in adjustment, survivors who appear at risk for problems should be screened to minimize adverse quality of life," senior study author Dr. Ann C. Mertens, of Emory University in Atlanta, told Reuters Health.

She and her colleagues report the findings in the Journal of Clinical Oncology.

While the majority of children diagnosed with cancer now survive, it's known that they face health risks as they grow older.

These effects vary widely and depend on a number of factors, such as the type of cancer and the type and duration of treatment. They can include anything from problems with memory, attention or intellectual ability to damage to the heart, lungs or other organs. Treatments for certain cancers may harm hearing or vision, while some can affect future fertility.

Childhood cancer survivors are also at greater-than-average risk of developing a second cancer later in life.

Based on questionnaires given to parents of nearly 3,000 former cancer patients, teenage survivors were 50 percent more likely to suffer from depression or anxiety symptoms than their siblings. They were also 70 percent more likely to show antisocial behavior, such as problems getting along with their peers.

In addition, teens who'd survived leukemia or central nervous system cancers tended to have more symptoms of attention-deficit hyperactivity disorder.

Certain cancer treatments were particularly associated with these problems, including brain radiation and intra-spinal injections of the cancer drug methotrexate. These therapies can directly affect the functioning of the central nervous system.

For parents, the current findings mean that they should be on the lookout for behavior changes in their children, according to Mertens.

"Parents should be aware of possible changes in their adolescent's behavior," she explained, "since the meaning of the cancer experience and the effects of survivorship may change during adolescence."

Teenagers who are having problems, she noted, should be evaluated by a psychologist with experience in treating childhood cancer survivors.

SOURCE: Journal of Clinical Oncology, August 20, 2007.