Table 2.
Characteristics in DCIS patients treated with HF-WBI vs. CF-WBI
| CF-WBI | HF-WBI | % HF-WBI | AOR (95% CI)* | Chi-square† | |
|---|---|---|---|---|---|
| Age at diagnosis | |||||
| <40 | 2,275 | 91 | 3.8 | 1.0 (ref.) | 1140.16 |
| 40–44 | 9,117 | 388 | 4.1 | 0.45 (0.16–1.25) | |
| 45–49 | 14,819 | 754 | 4.8 | 0.55 (0.20–1.53) | |
| 50–54 | 16,566 | 1,091 | 6.2 | 0.68 (0.25–1.88) | |
| 55–59 | 17,435 | 1,352 | 7.2 | 0.90 (0.33–2.48) | |
| 60–64 | 15,733 | 1,495 | 8.7 | 1.00 (0.36–2.75) | |
| 65–69 | 13,774 | 1,516 | 9.9 | 1.25 (0.45–3.44) | |
| 70–74 | 9,351 | 1,183 | 11.2 | 1.67 (0.61–4.61) | |
| 75–79 | 5,870 | 879 | 13.0 | 2.34 (0.85–6.46) | |
| 80+ | 2,926 | 666 | 18.5 | 3.80 (1.37–10.52) | |
|
| |||||
| Race/ethnicity | |||||
| White | 84,040 | 7,177 | 7.9 | 1.0 (ref.) | 37.75 |
| Black | 12,961 | 999 | 7.2 | 0.85 (0.76–0.94) | |
| Hispanic | 5,066 | 502 | 9.0 | 1.02 (0.89–1.17) | |
| Asian | 4,084 | 567 | 12.2 | 1.39 (1.22–1.58) | |
| Other/unknown | 1,715 | 170 | 9.0 | 1.06 (0.84–1.35) | |
|
| |||||
| Insurance status | |||||
| Not Insured | 1,689 | 166 | 8.9 | ||
| Private Insurance | 69,658 | 4,965 | 6.7 | ||
| Medicaid | 4,717 | 396 | 7.7 | ||
| Medicare | 29,333 | 3,704 | 11.2 | ||
| Other Government | 1,094 | 79 | 6.7 | ||
| Insurance Status Unknown | 1,375 | 105 | 7.1 | ||
|
| |||||
| Charlson/Deyo comorbidity index | |||||
| 0 | 95,873 | 8,191 | 7.9 | ||
| 1 | 10,371 | 1,058 | 9.3 | ||
| 2 | 1,622 | 166 | 9.3 | ||
|
| |||||
| Tumor size in DCIS | |||||
| <= 1.0 cm | 42,610 | 4,185 | 8.9 | 1.0 (ref.) | 73.77 |
| 1.1–2.0 cm | 19,994 | 1,825 | 8.4 | 0.80 (0.74–0.85) | |
| 2.1–3.0 cm | 6,159 | 606 | 9.0 | 0.76 (0.68–0.85) | |
| >3.0 cm | 5,464 | 506 | 8.5 | 0.71 (0.63–0.80) | |
|
| |||||
| Laterality | |||||
| Right | 52,530 | 4,699 | 8.2 | ||
| Left | 55,276 | 4,713 | 7.9 | ||
|
| |||||
| Histology in DCIS | |||||
| Ductal | 81,169 | 7,183 | 8.1 | ||
| Ductal & lobular | 3,202 | 277 | 8.0 | ||
| Comedocarcinoma | 10,393 | 670 | 6.1 | ||
| Cribriform | 9,511 | 989 | 9.4 | ||
| Papillary | 2,610 | 228 | 8.0 | ||
| Paget's disease | 273 | 21 | 7.1 | ||
| Others | 708 | 47 | 6.2 | ||
|
| |||||
| Grade | |||||
| 1 | 13,453 | 1,098 | 7.5 | ||
| 2 | 34,804 | 3,375 | 8.8 | ||
| 3 | 37,059 | 3,261 | 8.1 | ||
|
| |||||
| Estrogen receptor & hormone therapy | |||||
| Negative | 13,956 | 1,206 | 8.0 | 1.0 (ref.) | 27.01 |
| Positive, no hormone therapy | 27,264 | 3,176 | 10.4 | 1.19 (1.09–1.31) | |
| Positive, with hormone therapy | 47,521 | 4,087 | 7.9 | 1.02 (0.93–1.11) | |
|
| |||||
| Surgical margin | |||||
| Negative | 103,126 | 9,108 | 8.1 | ||
| Positive | 3,840 | 250 | 6.1 | ||
|
| |||||
| Facility location | |||||
| New England | 9,282 | 400 | 4.1 | 1.0 (ref.) | 807.42 |
| Middle Atlantic | 17,025 | 1,732 | 9.2 | 1.61 (1.38–1.88) | |
| South Atlantic | 21,889 | 1,910 | 8.0 | 1.97 (1.69–2.29) | |
| East North Central | 21,932 | 1,996 | 8.3 | 2.09 (1.80–2.43) | |
| East South Central | 5,181 | 300 | 5.5 | 1.22 (0.98–1.51) | |
| West North Central | 8,232 | 633 | 7.1 | 1.72 (1.45–2.04) | |
| West South Central | 5,530 | 285 | 4.9 | 1.45 (1.18–1.77) | |
| Mountain | 3,803 | 798 | 17.3 | 5.72 (4.82–6.80) | |
| Pacific | 12,717 | 1,270 | 9.1 | 2.39 (2.04–2.79) | |
|
| |||||
| Facility type & volume | 578.50 | ||||
| In community cancer program | |||||
| <120 | 22,125 | 985 | 4.3 | 1.0 (ref.) | |
| 120–207 | 19,954 | 1,425 | 6.7 | 1.74 (1.56–1.93) | |
| 208–342 | 17,222 | 1,198 | 6.5 | 1.55 (1.38–1.73) | |
| 343+ | 9,387 | 877 | 8.5 | 1.85 (1.63–2.09) | |
| In academic/research program | |||||
| <120 | 1,637 | 72 | 4.2 | 1.0 (ref.) | |
| 120–207 | 4,650 | 395 | 7.8 | 1.55 (1.11–2.17) | |
| 208–342 | 10,400 | 1,020 | 8.9 | 1.87 (1.36–2.58) | |
| 343+ | 12,300 | 2,448 | 16.6 | 3.02 (2.21–4.14) | |
|
| |||||
| Median income | |||||
| <$30000 | 14,509 | 1,048 | 6.7 | 1.0 (ref.) | 58.9 |
| $30000–34999 | 21,970 | 1,657 | 7.0 | 1.16 (1.04–1.30) | |
| $35,000–45999 | 28,691 | 2,347 | 7.6 | 1.28 (1.15–1.43) | |
| $46,000+ | 41,768 | 4,319 | 9.4 | 1.49 (1.34–1.67) | |
|
| |||||
| Urban/Rural | |||||
| Large metropolis (pop. ≥1 million) | 57,221 | 5,952 | 9.4 | 1.0 (ref.) | 180.40 |
| Metropolis (pop. <1 million) | 34,551 | 2,167 | 5.9 | 0.72 (0.67–0.77) | |
| Urban (pop. ≥20000) | 5,682 | 335 | 5.6 | 0.72 (0.61–0.85) | |
| Urban (pop. 2500–19999) | 6,052 | 575 | 8.7 | 1.39 (1.20–1.61) | |
| Rural | 1,317 | 161 | 10.9 | 1.91 (1.51–2.41) | |
|
| |||||
| Distance to facility | |||||
| < 5.0 miles | 37,038 | 3,073 | 7.7 | 1.0 (ref.) | 19.08 |
| 5.0–9.9 miles | 28,754 | 2,394 | 7.7 | 0.93 (0.86–1.00) | |
| 10.0–19.9 miles | 23,820 | 2,066 | 8.0 | 0.94 (0.86–1.02) | |
| 20.0–49.9 miles | 13,718 | 1,306 | 8.7 | 1.01 (0.91–1.12) | |
| ≥ 50.0 miles | 3,708 | 538 | 12.7 | 1.28 (1.09–1.49) | |
*
Calculated from multivariable logistic regression, adjusting for year of diagnosis and all other variables with adjusted odds ratios in the table. Variables without adjusted odds ratios were not included in the final logistic regression model.
†
All p-values <0.001
Abbreviations: HF-WBI, hypofractionated whole breast irradiation; CF-WBI, conventional fractionated whole breast irradiation; DCIS, ductal carcinoma in situ; pop., population; AOR, adjusted odds ratio; CI, confidence interval