CONGENITAL-ABNORMALITIES IN CHILDREN WITH CANCER AND THEIR RELATIVES - RESULTS FROM A CASE-CONTROL STUDY (IRESCC)

Several studies have revealed an excess of malformations in children w ith certain malignancies. A few environmental causes have been identif ied which may damage the foetus and lead to malformation and cancer. H owever, most of the numerous recognised cancer/malformation syndromes are genetically determined. This report describes a case-control study of 555 newly diagnosed children with cancer and 1,110 matched control s, chosen from general practitioner lists (GP controls) and hospital a dmissions (H controls). Their parents were interviewed on topics of po ssible aetiological significance and medical records were checked to c onfirm reports at interview. The numbers of.congenital malformations i n the index and GP control children, and the relatives of the index ch ildren, the GP and H controls are described. There were more children with malformations among the cases (60/555) than among the GP controls (27/555), P<0.001. The abnormalities in the cases included eight with specific chromosomal/genetic conditions (e.g. Down's syndrome, XY gon adal dysgenesis, Von Recklinghausen's neurofibromatosis, Goldenhar's s yndrome) whereas only one GP control child had a chromosomal defect (P <0.05). Five case children but no GP controls had' neural tube defects ; this is not statistically significant. No excess of malformations wa s found in the siblings of cases compared with GP and H control siblin gs. Case mothers had a small excess of malformations (22/555) compared with GP controls (8/555), P<0.05. Among more distant relatives the re sults were difficult to interpret because of the relatively small numb ers in the diagnostic subgroups and because of apparent under reportin g in grandparents, but no striking differences were seen between case and control relatives. The excess of malformations found in children w ith cancer, compared with controls, without a similar excess of malfor mations in their close relatives may indicate that in some (perhaps ve ry roughly one in 20) cases antenatal events may lead both to the malf ormation and the malignancy.