Table 2.
Proportion of patients treated with radiotherapy increased over time for various breast cancer stages but for T1aN0 patients.
| Stage | 1988 to 1997 | 1998 to 2007 | 2008 to 2012 | Relative change |
|---|---|---|---|---|
| DCIS | 34.9% (N=3,163) | 39.4% (N=6,159) | 41.1% (N=1,793) | + 17.8% |
| T1aN0 | 65.1% (N=8,654) | 54.0% (N=21,346) | 53.0% (N=14,372) | - 18.6% |
| T1bN0 | 49.6% (N=23,010) | 59.2% (N=58,503) | 57.1% (N=34,269) | + 15.1% |
| T1cN0 | 43.1% (N=40,785) | 53.3% (N=100,921) | 52.1% (N=58,396) | + 21.0% |
| Stage IIA – T2 | 30.2% (N=22,204) | 41.1% (N=55,816) | 41.2% (N=36,798) | + 36.4% |
| Stage IIA – N1 | 39.1% (N=13,718) | 51.9% (N=41,282) | 53.8% (N=21,761) | + 37.6% |
| Stage IIB | 31.0% (N=13,656) | 45.9% (N=41,238) | 50.2% (N=27,025) | + 61.9% |
| Stage IIIA | 39.5% (N=12,939) | 61.9% (N=29,419) | 64.5% (N=16,875) | + 63.3% |
| Stage IIIB | 44.7% (N=4,762) | 50.0% (N=11,179) | 53.0% (N=5,726) | + 18,6% |
| Stage IIIC | 45.3% (N=7,060) | 61.6% (N=14,753) | 62.3% (N=8,103) | + 37.5% |
The variations for each stage are statistically significant (p < .001).