Table 3. Risk of SMN after nonretinoblastoma childhood cancer, by duration of follow-up from original diagnosis.
|
Follow-up period from diagnosis (in years) |
||||
|---|---|---|---|---|
| 3–9 | 10–19 | 20–29 | 30 or more | |
| Number entering risk period | 15 452 | 7862 | 2806 | 808 |
| Person-years accrued during risk period | 76 594 | 50 685 | 16 695 | 3189 |
| Observed number of SMNs | 92 | 64 | 34 | 11 |
| SIR (O/E) | 10.2 | 5.7 | 3.5 | 2.4 |
| 95% CI for SIRs | 8.3, 12.6 | 4.4, 7.3 | 2.4, 4.9 | 1.2, 4.3 |
| AER per 1000 survivors per year | 1.1 | 1.0 | 1.5 | 2.0 |
SMN=second malignant neoplasm; O=observed; E=expected; SIR=standardised incidence ratio; AER=additive excess risk.
Statistical test for trend in SIR (unadjusted), P<0.001.
Statistical test for trend in SIR (adjusted), P=0.002.
Statistical test for heterogeneity in SIR (unadjusted), P<0.001.
Statistical test for heterogeneity in SIR (adjusted), P=0.006.