Family history of cancer in children and adolescents with germ cell tumours: a report from the Children's Oncology Group.

BACKGROUND

Studies of family history of cancer in paediatric germ cell tumours (GCTs) are few, and none has had sufficient sample size to specifically evaluate family history of GCT.

METHODS

We utilised family history data from a paediatric GCT study to calculate standardised incidence ratios (SIR) for GCT and other cancers using age- and sex-specific incidence rates from the SEER Program.

RESULTS

This analysis included 7998 relatives of paediatric GCT probands. We observed a higher number of GCT cases than expected in male and female relatives of probands (SIR=2.38, 95% CI 1.25, 3.51 for males; SIR=14.3, 95% CI 0.29, 28.4 for females). Further, we observed a particularly strong SIR for relatives of probands with intracranial GCT (SIR=8.07, 95% CI 3.51, 12.6). The SIR for relatives of probands with ovarian GCT was also elevated but did not reach statistical significance (SIR 4.35, 95% CI 0-9.27). Other notable associations include elevated SIRs for melanoma in male relatives and reduced SIRs for lymphatic/haematologic malignancies in male and female relatives.

CONCLUSIONS

These results support the hypothesis that familial aggregation of GCT occurs in males and females.