Dr Jan Alsner told ECCO12 The European Cancer Conference today (Wednesday 24 September) that this finding was independent of whether the children had been treated with radiotherapy or not; none of them had had chemotherapy, thus enabling Dr Alsner and his colleagues to make reliable calculations about the effect of radiotherapy. (Previous research had suggested radiotherapy could be the reason for a greater number of second primary tumours).
In the world's longest-running, complete population-based study, the researchers tracked down data on 266 retinoblastoma patients, covering a 57-year period from 1943 to 2000**. Much of the data came from the Danish Cancer Registry, which is the oldest registry in the world; it was able to give details on the treatment of every retinoblastoma case in Denmark, and family details of all the cases tracked (identifying parents, siblings, children etc).
They found that 22 of the 236 retinoblastoma survivors had gone on to develop a second, primary tumour. Among the 148 patients with non-hereditary retinoblastoma, there were seven cases of a second, primary cancer; but among the 88 patients with hereditary retinoblastoma, there were 15 cases of a second, primary cancer.
Dr Alsner, an associate professor at the Department of Experimental Clinical Oncology at Aarhus University Hospital, Denmark, said: "Forty years after treatment for retinoblastoma, the cumulative risk of developing and dying from a second primary cancer in the non-hereditary group during that time was similar to the general population at five and three per cent respectively. However, among the hereditary group, the cumulative risk was significantly higher, a
Contact: Emma Mason
Federation of European Cancer Societies