Table 2.
Characteristics in DCIS patients treated with HF-WBI vs. CF-WBI
| CF-WBI (n=126,658) |
HF-WBI (n=26,216) |
%HF-WBI | AOR (95% CI) a | Chi-square* | |
|---|---|---|---|---|---|
| Age at diagnosis | 1430.69 | ||||
| <40 | 2,597 | 190 | 6.82 | 1.0 (ref) | |
| 40–44 | 10,863 | 1,037 | 8.71 | 0.67 (0.52–0.86) | |
| 45–49 | 17,313 | 2,082 | 10.73 | 0.93 (0.73–1.18 | |
| 50–54 | 19,450 | 3,379 | 14.80 | 1.34 (1.06–1.71) | |
| 55–59 | 20,450 | 4,116 | 16.75 | 1.62 (1.28–2.05) | |
| 60–64 | 18,737 | 4,486 | 19.32 | 1.91 (1.50–2.42) | |
| 65–69 | 16,716 | 4,510 | 21.25 | 2.17 (1.70–2.76) | |
| 70–74 | 10,859 | 3,289 | 23.25 | 2.92 (2.28–3.73) | |
| 75–79 | 6,567 | 1,960 | 22.99 | 3.92 (3.05–3.73) | |
| 80+ | 3,106 | 1,167 | 27.31 | 6.84 (5.29–8.86) | |
|
| |||||
| Race/ethnicity | 121.84 | ||||
| White | 97,695 | 19,836 | 16.88 | 1.0 (ref) | |
| Black | 15,813 | 2,867 | 15.35 | 0.79 (0.74–0.85) | |
| Hispanic | 6,225 | 1,393 | 18.29 | 0.91 (0.82–1.00) | |
| Asian | 4,923 | 1,697 | 25.63 | 1.44 (1.32–1.58) | |
| Other/unknown | 2,002 | 423 | 17.44 | 0.95 (0.80–1.12) | |
|
| |||||
| Insurance status | 25.44 | ||||
| Not Insured | 1,940 | 371 | 16.05 | 1.49 (1.27–1.75) | |
| Private Insurance | 81,418 | 14,508 | 15.12 | 1.0 (ref) | |
| Medicaid | 5,936 | 1,198 | 16.79 | 0.97 (0.88–1.07) | |
| Medicare | 34,392 | 9,603 | 21.83 | 1.02 (0.96–1.09) | |
| Other Government | 1,388 | 262 | 15.88 | 0.94 (0.77–1.14) | |
| Insurance Status Unknown | 1,584 | 274 | 14.75 | 0.99 (0.81–1.22) | |
|
| |||||
| Charlson/Deyo comorbidity index | 17.41 | ||||
| 0 | 111,343 | 22,412 | 16.76 | 1.0 (ref) | |
| 1 | 12,943 | 3,093 | 19.29 | 0.88 (0.83–0.94) | |
| 2 | 1,911 | 529 | 21.68 | 0.89 (0.77–1.03) | |
| ≥3 | 461 | 182 | 28.30 | 0.92 (0.69–1.23) | |
|
| |||||
| Tumor size in DCIS | 105.61 | ||||
| ≤ 1.0 cm | 48,101 | 8,392 | 14.85 | 1.0 (ref) | |
| 1.1–2.0 cm | 23,284 | 4,218 | 15.34 | 0.85 (0.81–0.89) | |
| 2.1–3.0 cm | 7,292 | 1,427 | 16.37 | 0.81 (0.76–0.87) | |
| >3.0 cm | 6,515 | 1,195 | 15.50 | 0.72 (0.67–0.78) | |
|
| |||||
| Laterality | 22.03 | ||||
| Right | 61,535 | 13,156 | 17.61 | 1.0 (ref) | |
| Left | 65,072 | 13,055 | 16.71 | 0.91 (0.87–0.95) | |
|
| |||||
| Histology in DCIS | 53.71 | ||||
| Ductal | 95,208 | 20,004 | 17.36 | 1.0 (ref) | |
| Ductal & lobular | 3,675 | 688 | 15.77 | 0.90 (0.79–1.03) | |
| Comedocarcinoma | 12,446 | 2,079 | 14.31 | 0.82 (0.77–0.88) | |
| Cribriform | 11,347 | 2,660 | 18.99 | 1.13 (1.06–1.21) | |
| Papillary | 2,952 | 628 | 17.54 | 1.11 (0.98–1.26) | |
| Paget’s disease | 315 | 77 | 19.64 | 0.90 (0.60–1.34) | |
| Others | 715 | 80 | 10.06 | 0.78 (0.55–1.10) | |
|
| |||||
| Grade | |||||
| 1 | 15,372 | 2,979 | 16.23 | ||
| 2 | 41,909 | 9,783 | 18.93 | ||
| 3 | 44,630 | 9,813 | 18.02 | ||
|
| |||||
| Estrogen receptor | |||||
| Negative | 16,418 | 3,548 | 17.77 | ||
| Positive | 95,599 | 21,842 | 18.60 | ||
|
| |||||
| Surgical margin | 12.46 | ||||
| Negative | 121,253 | 25,412 | 17.33 | 1.0 (ref) | |
| Positive | 4,383 | 671 | 13.28 | 0.80 (0.71–0.91) | |
|
| |||||
| Facility locationb | 829.62 | ||||
| New England | 10,963 | 1,740 | 13.70 | 1.0 (ref) | |
| Middle Atlantic | 20,629 | 4,716 | 18.61 | 1.05 (0.95–1.16) | |
| South Atlantic | 25,891 | 5,200 | 16.73 | 1.29 (1.18–1.42) | |
| East North Central | 25,097 | 5,336 | 17.53 | 1.35 (1.23–1.48) | |
| East South Central | 6,413 | 1,159 | 15.31 | 1.02 (0.90–1.16) | |
| West North Central | 9,802 | 1,926 | 16.42 | 1.34 (1.20–1.50) | |
| West South Central | 6,930 | 951 | 12.07 | 0.82 (0.72–0.94) | |
| Mountain | 4,102 | 1,595 | 28.00 | 3.72 (3.31–4.19) | |
| Pacific | 14,234 | 3,403 | 19.29 | 1.49 (1.35–1.65) | |
|
| |||||
| Facility volume, number of breast cancers per year | 460.90 | ||||
| <120 | 27,201 | 3,658 | 11.85 | 1.0 (ref) | |
| 120–207 | 32,772 | 5,722 | 14.86 | 1.40 (1.31–1.49) | |
| 208–342 | 35,404 | 7,061 | 16.63 | 1.46 (1.37–1.57) | |
| 343+ | 30,774 | 9,120 | 22.86 | 2.08 (1.94–2.23) | |
|
| |||||
| Facility type | 280.67 | ||||
| Community Cancer Program | 72,248 | 11,971 | 14.21 | 1.0 (ref) | |
| Integrated Network Cancer Program | 18,251 | 4,145 | 18.51 | 1.31 (1.24–1.40) | |
| Academic/Research Program | 33,562 | 9,910 | 22.80 | 1.54 (1.46–1.62) | |
|
| |||||
| Median household income of residential zip code | 61.52 | ||||
| <$38,000 | 17,349 | 3,053 | 14.96 | 1.0 (ref) | |
| $38,000-$47,999 | 25,658 | 4,758 | 15.64 | 1.07 (1.00–1.16) | |
| $48,000-$62,999 | 33,701 | 6,731 | 16.65 | 1.15 (1.07–1.24) | |
| ≥$63,000 | 49,360 | 11,614 | 19.05 | 1.29 (1.20–1.39) | |
|
| |||||
| Distance to facility | |||||
| < 5.0 miles | 43,105 | 8,156 | 15.91 | ||
| 5.0–9.9 miles | 33,707 | 6,758 | 16.70 | ||
| 10.0–19.9 miles | 28,361 | 6,186 | 17.91 | ||
| 20.0–49.9 miles | 16,465 | 3,751 | 18.55 | ||
| ≥ 50.0 miles | 4,545 | 1,321 | 22.52 | ||
|
| |||||
| Urban/Rural | 182.33 | ||||
| Large metropolis (pop. ≥1 million) | 67,695 | 15,769 | 18.89 | 1.0 (ref) | |
| Metropolis (pop. <1 million) | 40,507 | 6,931 | 14.61 | 0.78 (0.75–0.82) | |
| Urban (pop. ≥20000) | 6,515 | 1,087 | 14.30 | 0.87 (0.79–0.97) | |
| Urban (pop. 2500–19999) | 7,084 | 1,360 | 16.11 | 1.17 (1.06–1.28) | |
| Rural | 1,533 | 380 | 19.86 | 1.64 (1.39–1.94) | |
a
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.
b
Facility location: New England (CT, MA, ME, NH, RI, VT), Middle Atlantic (NJ, NY, PA), South Atlantic (DC, DE, FL, GA, MD, NC, SC, VA, WV), East North Central (IL, IN, MI, OH, WI), East South Central (AL, KY, MS, TN), West North Central (IA, KS, MN, MO, ND, NE, SD), West South Central (AR, LA, OK, TX), Mountain (AZ, CO, ID, MT, NM, NV, UT, WY), Pacific (AK, CA, HI, OR, WA).
*
All p-values <0.001
Abbreviations: HF-WBI, hypofractionated whole breast irradiation; CF-WBI, conventional fractionated whole breast irradiation; pop., population; AOR, adjusted odds ratio; CI, confidence interval