Table 3.
Cox proportional hazards models of death.
| All patients (n=3834) | Stage II (n=1914) | Stage III (n=1467) | |
|---|---|---|---|
| Brachytherapy | |||
| LDR | Referent | Referent | Referent |
| HDR | 0.93 (0.83–1.03) | 0.98 (0.83–1.16) | 0.91 (0.78–1.07) |
| Year of diagnosis | |||
| 2003 | Referent | Referent | Referent |
| 2004 | 0.94 (0.80–1.11) | 0.87 (0.69–1.10) | 0.94 (0.73–1.22) |
| 2005 | 0.97 (0.83–1.15) | 1.08 (0.84–1.38) | 0.88 (0.68–1.12) |
| 2006 | 0.94 (0.80–1.11) | 0.87 (0.69–1.11) | 0.92 (0.71–1.18) |
| Age | |||
| <40 | Referent | Referent | Referent |
| 40–49 | 1.07 (0.91–1.26) | 1.34 (1.05–1.70)* | 0.85 (0.66–1.10) |
| 50–59 | 1.06 (0.89–1.25) | 0.98 (0.75–1.29) | 1.00 (0.78–1.27) |
| 60–69 | 1.14 (0.94–1.37) | 1.19 (0.89–1.58) | 1.10 (0.83–1.47) |
| ≥70 | 1.48 (1.19–1.83)* | 1.49 (1.11–2.00)* | 1.34 (0.98–1.84) |
| Race | |||
| White | Referent | Referent | Referent |
| Black | 1.03 (0.91–1.18) | 0.90 (0.73–1.12) | 1.10 (0.90–1.34) |
| Hispanic | 0.75 (0.63–0.90)* | 0.56 (0.42–0.75)* | 0.90 (0.70–1.16) |
| Other | 0.70 (0.53–0.93)* | 0.55 (0.36–0.84)* | 0.72 (0.47–1.10) |
| Unknown | 1.05 (0.70–1.58) | 1.06 (0.58–1.95) | 1.19 (0.65–2.17) |
| Zip code income | |||
| <$30,000 | Referent | Referent | Referent |
| $30,000–$34,999 | 0.87 (0.74–1.03) | 0.81 (0.63–1.04) | 0.92 (0.70–1.21) |
| $35,000–$45,999 | 0.88 (0.74–1.04) | 0.86 (0.68–1.08) | 0.98 (0.75–1.30) |
| ≥$46,000 | 0.83 (0.67–1.02) | 0.83 (0.60–1.13) | 0.86 (0.63–1.17) |
| Unknown | 0.83 (0.58–1.20) | 0.93 (0.51–1.67) | 0.91 (0.54–1.53) |
| Education | |||
| <14% | Referent | Referent | Referent |
| 14–19.9% | 0.95 (0.79–1.13) | 0.93 (0.72–1.21) | 0.98 (0.77–1.24) |
| 20–28.9% | 0.98 (0.82–1.17) | 1.05 (0.80–1.36) | 0.90 (0.70–1.15) |
| ≥29% | 0.92 (0.75–1.14) | 0.86 (0.64–1.15) | 1.01 (0.75–1.36) |
| Unknown | NA | NA | NA |
| Insurance status | |||
| Commercial | Referent | Referent | Referent |
| Medicare | 1.24 (1.06–1.46)* | 1.63 (1.30–2.06)** | 0.97 (0.77–1.22) |
| Medicaid | 1.19 (1.04–1.35)* | 1.39 (1.12–1.72)* | 0.98 (0.81–1.19) |
| Uninsured | 0.97 (0.81–1.16) | 0.97 (0.72–1.31) | 0.97 (0.75–1.25) |
| Other | 1.26 (0.77–2.04) | 1.11 (0.54–2.28) | 1.08 (0.53–2.21) |
| Unknown | 1.18 (0.86–1.62) | 1.76 (1.11–2.80)* | 0.97 (0.62–1.53) |
| Comorbidity | |||
| 0 | Referent | Referent | Referent |
| 1 | 1.25 (1.08–1.46)* | 1.01 (0.80–1.28) | 1.38 (1.13–1.69)* |
| ≥2 | 1.75 (1.31–2.33)** | 2.78 (1.74–4.45)** | 1.17 (0.82–1.68) |
| Region | |||
| Northeast | Referent | Referent | Referent |
| Midwest | 1.02 (0.89–1.16) | 1.07 (0.87–1.31) | 0.96 (0.79–1.16) |
| South | 1.04 (0.91–1.19) | 1.16 (0.94–1.43) | 1.02 (0.85–1.22) |
| West | 0.98 (0.81–1.18) | 1.32 (1.01–1.72)* | 0.90 (0.71–1.13) |
| Metropolitan location | |||
| Metropolitan | Referent | Referent | Referent |
| Urban | 1.08 (0.95–1.22) | 1.09 (0.89–1.33) | 1.09 (0.90–1.32) |
| Rural | 0.88 (0.65–1.20) | 0.69 (0.42–1.12) | 0.82 (0.50–1.34) |
| Unknown | 0.85 (0.62–1.17) | 0.58 (0.33–1.00) | 0.98 (0.65–1.47) |
| Hospital type | |||
| Academic | Referent | Referent | Referent |
| Community cancer program | 1.23 (1.00–1.51) | 1.33 (0.98–1.81) | 1.20 (0.85–1.71) |
| Comprehensive community cancer program | 1.12 (1.00–1.25) | 1.03 (0.87–1.21) | 1.20 (1.03–1.38)* |
| Other | 1.50 (0.61–3.73) | 1.73 (0.83–3.60) | 0.58 (0.05–6.11) |
| Hospital volume | |||
| Lowest | Referent | Referent | Referent |
| Second | 1.13 (0.98–1.30) | 1.13 (0.92–1.39) | 1.10 (0.89–1.35) |
| Third | 0.98 (0.85–1.14) | 0.92 (0.74–1.15) | 0.95 (0.77–1.16) |
| Highest | 1.12 (0.97–1.28) | 0.99 (0.80–1.23) | 1.18 (0.98–1.44) |
| Histology | |||
| Squamous | Referent | Referent | Referent |
| Adenocarcinoma | 1.24 (1.05–1.45)* | 1.20 (0.93–1.56) | 1.43 (1.11–1.85)* |
| Adenosquamous | 1.30 (0.96–1.76) | 1.05 (0.63–1.73) | 1.47 (0.93–2.32) |
| Other | 1.27 (1.06–1.54)* | 1.37 (1.00–1.86)* | 1.19 (0.92–1.53) |
| Grade | |||
| 1 | Referent | Referent | Referent |
| 2 | 1.12 (0.88–1.42) | 1.20 (0.80–1.80) | 0.93 (0.69–1.27) |
| 3 | 1.29 (1.01–1.64) | 1.44 (0.96–2.15) | 1.13 (0.82–1.56) |
| Unknown | 1.06 (0.83–1.34) | 1.11 (0.74–1.65) | 0.94 (0.69–1.28) |
| Stage | |||
| IB2 | Referent | - | - |
| IIA | 1.36 (0.60–3.11) | Referent | - |
| IIB | 1.38 (1.12–1.70)* | 0.94 (0.42–2.09) | - |
| IINOS | 1.30 (1.01–1.68)* | 0.86 (0.39–1.91) | - |
| IIIA | 2.22 (1.60–3.09)** | - | Referent |
| IIIB | 2.47 (2.02–3.01)** | - | 1.04 (0.78–1.39) |
| III NOS | 1.97 (1.27–3.04)* | - | 0.84 (0.51–1.36) |
| IVA | 3.52 (2.63–4.72)** | - | - |
| Chemotherapy | |||
| No | Referent | Referent | Referent |
| Yes | 0.71 (0.61–0.82)** | 0.71 (0.59–0.86)* | 0.78 (0.61–0.99)* |
| Unknown | 0.50 (0.25–0.98)** | 0.62 (0.27–1.41) | 0.51 (0.21–1.23) |
| Radiation duration | |||
| 6–10 weeks | Referent | Referent | Referent |
| <6 weeks | 1.05 (0.94–1.18) | 1.02 (0.85–1.22) | 1.16 (0.97–1.38) |
| 10 weeks-6 months | 1.16 (1.02–1.32)* | 1.33 (1.09–1.62)* | 1.04 (0.88–1.23) |
| >6 months | 1.47 (0.81–2.67) | 2.49 (1.02–6.09)* | 1.01 (0.37–2.76) |
| Unknown | 1.03 (0.81–1.32) | 0.98 (0.63–1.51) | 0.84 (0.53–1.35) |
*
P<0.05,
**
P<0.0001