In Australia, over 80 % of children survive childhood cancer although the vast majority of survivors lead normal lives, two thirds of young adult survivors of childhood cancer suffer long term health complications from their earlier treatment which impact their quality of life.

As the numbers of survivors of childhood cancer increases, studies of the long-term survivors allows research which can guide newer treatment protocols and further improve the outlook for newly diagnosed patients.

When compared with the general population, survivors of childhood cancer in Australia are at an increased risk of second cancers and an earlier death, according to a study published in the Medical Journal of Australia, which looked at a group of survivors treated between 1970 and 1999.

The study led by researchers at Children's Cancer Institute Australia for Medical Research and the Sydney Children's Hospital, Randwick, involved 896 children treated over three decades at Sydney Children's Hospital, Randwick in Sydney.

"Identifying those at increased risk of late effects of treatment, including second cancers or [earlier death] has resulted in the modification of current childhood cancer treatments to minimise long term health complications in present and future patients," said, A/Prof Richard Cohn, co-author and Head of Clinical oncology at the Centre for Children's Cancer and Blood Disorders at the Sydney Children's Hospital, Randwick."

"Our results highlight that it is important for cancer survivors to be aware of the risk factors for complications of treatment and second cancers and maintain good follow-up health care. Although the risk is higher, the actual number of people who will get a second cancer is relatively small and each cancer survivor's experience is unique. Early detection of problems and intervention can minimise the impact on quality of life for the individual patient. A/Prof Cohn explained "Long-term follow-up clinics for survivors are provided at Sydney Children's Hospital."

"While we will continue to look at how current therapies can be further improved, our ultimate goal is to pinpoint the genetic markers that modify the impact of cancer therapies, and determine the risk of childhood cancer survivors developing long term health conditions, said Dr Lesley Ashton, lead author and Head of the Molecular Epidemiology Group at the Children's Cancer Institute Australia for Medical Research.

"If we can map the genetic factors, we can develop more individualised cancer treatments that do not result in long term health complications. Characterising survivors at risk of the late effects of cancer therapy is the first step in this process," explained Dr Ashton.

The study revealed that the survivors of childhood cancer relative to the NSW population had a 4.98-fold higher rate of second cancer and 7.46 times increased risk of earlier death. The risk of death of childhood cancer survivors was double in females compared to males.

The leading causes of earlier death included recurrence of the primary childhood cancer (55 per cent) and second cancers (12 per cent), as well as treatment-related complications (17 per cent).

Overall the number of deaths in childhood cancer survivors is low, but knowing the rate of death in this group compared to the general population is important when planning treatment and research.

Research suggests that changes to treatment approaches over the time of the study will further decrease these risks.

The researchers are expanding this hospital-based cohort study and looking for participants in a NSW and ACT study of childhood cancer survivors to assist in research examining the long term health outcomes of cancer therapy in survivors of childhood cancers.

Source: Children's Cancer Institute Australia