Infections may be linked to child cancer-study

By Patricia Reaney

LONDON (Reuters) – Common infections that affect mothers and babies may trigger certain types of childhood cancers, researchers said on Monday.

They found that leukemia and brain tumors, leading cancers in children, occurred in clusters which suggests that outbreaks of infections are a contributing cause of the disease.

"We found that place of birth was particularly significant, which suggests that an infection in the mother while she is carrying her baby, or in a child’s early years, could be a trigger factor for the cancer," said Dr Richard McNally, of the University of Newcastle upon Tyne in northern England.

"These could be minor, common illnesses … such a cold, mild flu or a respiratory infection," he added in a statement.

McNally and a team of researchers from England and Scotland, who reported the findings in the European Journal of Cancer, said the results could improve understanding about how cancer develops and may lead to better prevention and treatment.

The results support the findings from an earlier study by the Leukemia Research Fund (LRF) in Britain.

"It is pleasing that the conclusion from this research, which has used a different study group, is consistent with all the biological and epidemiological evidence, which points to an infectious challenge as the most plausible explanation of the cause of childhood leukemia," said Dr David Grant, of the LRF.

BETTER SURVIVAL RATES

Although cancer in children is rare, rates of the disease in youngsters in Europe have increased over the past three decades. Survival rates however have improved. Five-year survival rates are about 75 percent in western Europe and 63 percent in eastern Europe.

Leukemia is the most common childhood cancer, accounting for nearly one-third of all cases.

The researchers believe an infection in the womb or early in life could lead to cancer in young people who already carry mutant cells that would make them more vulnerable to the disease.

"Infections could be a trigger for the onset of the cancer in a limited number of susceptible individuals, those with a genetic predisposition," McNally said in an interview.

The findings are based on a statistical analysis of data from the Manchester Children’s Tumour Register, which recorded all cases of childhood cancers diagnosed between January 1954 and December 1998.

Researchers looked for unusual patterns of cancer linked to the time and place of children’s birth and where they were living when diagnosed with cancer.

In some clusters, they found 8 percent more cases of leukemia than would normally be expected and a 13 percent above-average incidence of the brain tumour astrocytoma.