Table 4.
The associations between demographic, clinical, and treatment variables and overall survival using the flexible parametric survival model, stratified by proxy subtype, in patients aged <70 years.
| All patients aged < 70 years | Luminal A | Luminal B, HER2-negative | ||||
|---|---|---|---|---|---|---|
| Unadjusted | Adjusted^ | Unadjusted | Adjusted^ | Unadjusted | Adjusted^ | |
| HR (95%CI) | HR (95%CI) | HR (95%CI) | HR (95%CI) | HR (95%CI) | HR (95%CI) | |
| Surgery | ||||||
| Yes | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| No | 6.97 (6.28–7.74) | 2.26 (1.80–2.83) | 12.92 (9.30–17.95) | 2.85 (1.31–6.18) | 14.04 (9.78–20.14) | 6.43 (2.62–15.80) |
| Chemotherapy | ||||||
| Yes | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| No | 1.51 (1.35–1.70) | 1.25 (1.11–1.41) | 1.51 (1.04–2.19) | 1.57 (1.03–2.39) | 1.19 (0.96–1.49) | 1.12 (0.87–1.45) |
| Not recommended | 0.47 (0.42–0.52) | 0.69 (0.60–0.80) | 0.64 (0.50–0.82) | 0.60 (0.32–1.12) | 0.14 (0.04–0.58) | 0.35 (0.08–1.43) |
| Radiotherapy | ||||||
| Yes | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| No | 2.50 (2.13–2.94) | 2.28 (1.94–2.67) | 2.12 (1.45–3.12) | 2.36 (1.53–3.64) | 2.25 (1.70–2.98) | 2.32 (1.68–3.21) |
| Not recommended | 0.68 (0.58–0.79) | 1.37 (1.14–1.64) | 1.18 (0.89–1.56) | 2.40 (1.60–3.61) | 0.52 (0.39–0.70) | 1.11 (0.73–1.67) |
| Endocrine therapy | ||||||
| Yes | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| No | 1.41 (1.17–1.69) | 1.70 (1.41–2.04) | 1.86 (1.29–2.69) | 1.71 (1.15–2.53) | 2.12 (1.55–2.90) | 1.81 (1.28–2.55) |
| Not recommended | 2.19 (1.95–2.45) | 1.82 (1.63–2.04) | — | — | — | — |
| Pre-surgical tumor size | ||||||
| ≤20 mm | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| 21–50 mm | 2.89 (2.48–3.35) | 1.78 (1.53–2.06) | 1.92 (1.49–2.48) | 1.40 (1.07–1.84) | 2.84 (1.94–4.16) | 1.83 (1.24–2.71) |
| >50 mm | 4.05 (3.41–4.81) | 2.66 (2.25–3.15) | 2.95 (2.17–4.02) | 2.30 (1.63–3.25) | 4.01 (2.62–6.14) | 2.24 (1.44–3.48) |
| Attached to chest wall | 11.71 (9.83–13.93) | 4.37 (3.63–5.21) | 7.58 (5.38–10.70) | 3.49 (2.37–5.13) | 9.66 (6.14–15.20) | 4.17 (2.59–6.71) |
| TNM nodal stage | ||||||
| N0 | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| N1 | 2.35 (2.00–2.74) | 1.71 (1.43–2.05) | 1.31 (0.94–1.83) | 0.87 (0.43–1.76) | 2.13 (1.51–2.99) | 1.66 (1.07–2.59) |
| N2 | 3.75 (3.14–4.49) | 2.98 (2.47–3.60) | 2.89 (2.02–4.13) | 2.03 (0.99–4.15) | 3.09 (2.12–4.53) | 2.63 (1.66–4.18) |
| N3 | 7.73 (6.60–9.04) | 4.54 (3.76–5.49) | 6.27 (4.39–8.95) | 4.39 (2.13–9.06) | 6.11 (4.38–8.54) | 5.42 (3.52–8.34) |
| Ethnicity | ||||||
| Chinese | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| Malay | 2.08 (1.87–2.31) | 1.56 (1.40–1.74) | 2.65 (2.07–3.39) | 1.78 (1.37–2.31) | 1.88 (1.49–2.38) | 1.59 (1.25–2.03) |
| Indian | 1.47 (1.24–1.73) | 1.15 (0.97–1.36) | 1.39 (0.90–2.12) | 1.28 (0.83–1.97) | 1.18 (0.79–1.78) | 0.87 (0.58–1.32) |
| Other | 1.07 (0.82–1.38) | 1.09 (0.84–1.41) | 1.64 (0.99–2.72) | 1.75 (1.05–2.93) | 0.92 (0.45–1.85) | 1.01 (0.50–2.06) |
| Age at diagnosis, years | ||||||
| <50 | 0.73 (0.67–0.80) | 0.78 (0.72–0.86) | 0.44 (0.33–0.58) | 0.42 (0.31–0.57) | 0.80 (0.66–0.98) | 0.85 (0.69–1.04) |
| 50–69 | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| Year of diagnosis | ||||||
| 2005–2010 | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| 2011–2015 | 0.96 (0.87–1.06) | 0.98 (0.90–1.08) | 0.89 (0.71–1.13) | 0.96 (0.75–1.24) | 0.81 (0.65–1.00) | 0.92 (0.73–1.16) |
| Surgery | ||||||
| Yes | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| No | 10.27 (7.79–13.53) | 2.55 (0.84–7.77) | 11.59 (8.25–16.26) | 1.62 (0.68–3.81) | 9.66 (6.89–13.55) | 5.46 (2.05–14.54) |
| Chemotherapy | ||||||
| Yes | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| No | 1.52 (1.16–2.01) | 1.23 (0.90–1.67) | 1.56 (1.10–2.20) | 1.23 (0.83–1.81) | 1.60 (1.22–2.10) | 1.48 (1.08–2.03) |
| Not recommended | 0.22 (0.07–0.76) | 0.54 (0.16–1.85) | 0.48 (0.23–0.99) | 1.34 (0.60–3.00) | 0.25 (0.05–1.15) | 0.71 (0.15–3.47) |
| Radiotherapy | ||||||
| Yes | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| No | 2.17 (1.51–3.13) | 3.11 (2.05–4.71) | 2.43 (1.52–3.86) | 2.64 (1.57–4.44) | 2.15 (1.52–3.05) | 2.68 (1.80–3.98) |
| Not recommended | 0.58 (0.41–0.81) | 2.79 (1.35–5.76) | 0.56 (0.37–0.85) | 1.91 (0.86–4.29) | 0.42 (0.30–0.60) | 0.64 (0.37–1.11) |
| Endocrine therapy | ||||||
| Yes | 1.00 (Reference) | 1.00 (Reference) | — | — | — | — |
| No | 1.46 (0.96–2.21) | 1.79 (1.13–2.83) | ||||
| Pre-surgical tumor size | ||||||
| ≤20 mm | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| 21–50 mm | 3.39 (2.31–4.96) | 2.06 (1.39–3.08) | 3.46 (1.96–6.09) | 1.95 (1.09–3.48) | 2.29 (1.59–3.31) | 1.72 (1.23–2.41) |
| >50 mm | 3.64 (2.33–5.68) | 2.22 (1.39–3.55) | 4.52 (2.46–8.29) | 2.61 (1.39–4.92) | 4.48 (3.01–6.66) | 3.16 (2.15–4.64) |
| Attached to chest wall | 10.77 (6.96–16.67) | 4.13 (2.54–6.70) | 14.65 (7.92–27.11) | 6.50 (3.39–12.48) | 6.02 (3.81–9.53) | 3.05 (1.90–4.88) |
| TNM nodal stage | ||||||
| N0 | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| N1 | 2.36 (1.64–3.38) | 3.55 (1.73–7.28) | 2.83 (1.79–4.46) | 3.31 (1.49–7.34) | 2.90 (1.95–4.30) | 1.61 (1.10–2.35) |
| N2 | 4.35 (3.02–6.28) | 7.21 (3.53–14.74) | 4.13 (2.60–6.56) | 5.89 (2.65–13.10) | 4.78 (3.09–7.40) | 2.63 (1.72–4.03) |
| N3 | 7.48 (5.01–11.18) | 11.96 (5.71–25.05) | 5.64 (3.58–8.88) | 6.35 (2.84–14.21) | 9.63 (6.50–14.29) | 6.93 (4.69–10.25) |
| Ethnicity | ||||||
| Chinese | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| Malay | 1.76 (1.32–2.34) | 1.16 (0.86–1.56) | 1.82 (1.26–2.62) | 1.74 (1.19–2.54) | 1.80 (1.34–2.42) | 1.44 (1.07–1.95) |
| Indian | 1.78 (1.18–2.70) | 1.11 (0.72–1.71) | 1.67 (0.93–3.01) | 1.32 (0.70–2.49) | 1.05 (0.68–1.62) | 0.76 (0.50–1.16) |
| Other | 0.42 (0.13–1.31) | 0.38 (0.12–1.19) | 1.55 (0.72–3.30) | 1.45 (0.67–3.17) | 0.81 (0.35–1.84) | 0.90 (0.40–2.04) |
| Age at diagnosis, years | ||||||
| <50 | 0.49 (0.38–0.63) | 0.54 (0.41–0.71) | 0.78 (0.57–1.06) | 0.93 (0.67–1.28) | 1.10 (0.88–1.38) | 1.17 (0.93–1.47) |
| 50–69 | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| Year of diagnosis | ||||||
| 2005–2010 | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) | 1.00 (Reference) |
| 2011–2015 | 0.85 (0.66–1.09) | 0.91 (0.70–1.19) | 0.92 (0.68–1.25) | 1.01 (0.73–1.40) | 1.08 (0.84–1.37) | 1.20 (0.93–1.54) |
HR: Hazards ratio, CI: Confidence interval. ^Adjusted for all variables listed in the table and site.