Table 1. The proposed TLNR classification in the training cohort.
| Stage | 5-Y OS, % (95% CI) | HR (95% CI)† | Log-rank (Mantel-Cox)‡ | |
|---|---|---|---|---|
| χ2 value | P value | |||
| Stage I | 83.1 (82.1–84.1) | – | – | – |
| T1LNR1 (n=5,260) | 83.4 (82.4–84.4) | 1.00 (reference) | – | – |
| T1LNR4 (n=23) | 73.9 (50.9–87.3) | 1.00 (0.45–2.24) | 0 | 0.999 |
| T1LNR2 (n=511) | 80.7 (77.0–83.9) | 1.06 (0.89–1.26) | 0.024 | 0.877 |
| Stage IIA | 75.0 (74.5–75.4) | – | – | – |
| T2LNR1 (n=8,941) | 78.8 (77.9–79.6) | 1.31 (1.23–1.40) | 5.79§ | 0.016 |
| T2LNR2 (n=1,465) | 76.8 (74.5–78.9) | 1.37 (1.24–1.52) | 0.925 | 0.336 |
| T1LNR3 (n=65) | 72.3 (59.7–81.6) | 1.50 (1.00–2.24) | 0.192 | 0.662 |
| T3LNR1 (n=22,931) | 73.3 (72.8–73.9) | 1.57 (1.49–1.66) | 0.067 | 0.796 |
| Stage IIB | 63.2 (62.3–64.0) | – | – | – |
| T2LNR3 (n=221) | 68.6 (62.0–74.3) | 1.75 (1.42–2.16) | 1.08§ | 0.298 |
| T2LNR4 (n=56) | 69.4 (55.5–79.8) | 1.83 (1.24–2.70) | 0.048 | 0.826 |
| T3LNR2 (n=10,504) | 63.6 (62.7–64.5) | 2.10 (1.98–2.23) | 0.434 | 0.510 |
| T1LNR5 (n=20) | 63.5 (38.3–80.7) | 2.35 (1.30–4.25) | 0.131 | 0.717 |
| T4aLNR1 (n=1,945) | 60.1 (57.8–62.2) | 2.40 (2.21–2.61) | 0.003 | 0.959 |
| Stage IIC | 49.7 (48.5–50.9) | – | – | – |
| T4bLNR1 (n=1,499) | 55.1 (52.5–57.6) | 2.72 (2.49–2.96) | 6.36§ | 0.012 |
| T3LNR3 (n=2,845) | 50.9 (49.0–52.7) | 2.99 (2.79–3.21) | 5.11 | 0.024 |
| T4aLNR2 (n=1,422) | 47.4 (44.7–49.9) | 3.25 (2.98–3.53) | 3.05 | 0.081 |
| T2LNR5 (n=46) | 43.5 (29.0–57.1) | 3.49 (2.43–5.00) | 0.168 | 0.682 |
| T3LNR4 (n=1,082) | 42.5 (39.6–45.5) | 3.73 (3.40–4.08) | 0.131 | 0.718 |
| Stage IIIA | 33.6 (31.7–35.4) | – | – | – |
| T4aLNR3 (n=490) | 38.6 (34.2–42.9) | 4.23 (3.76–4.76) | 2.92§ | 0.088 |
| T4bLNR2 (n=823) | 35.3 (32.0–38.6) | 4.68 (4.25–5.15) | 1.85 | 0.174 |
| T4aLNR4 (n=207) | 31.8 (25.6–38.2) | 4.99 (4.23–5.09) | 0.808 | 0.369 |
| T3LNR5 (n=997) | 30.0 (27.2–32.9) | 5.43 (4.97–5.93) | 1.06 | 0.304 |
| Stage IIIB | 22.2 (19.3–25.3) | – | – | – |
| T4bLNR3 (n=318) | 24.4 (19.8–29.3) | 6.52 (5.71–7.44) | 4.05§ | 0.044 |
| T4bLNR4 (n=148) | 22.3 (16.0–29.3) | 6.76 (5.63–8.11) | 0.098 | 0.754 |
| T4aLNR5 (n=288) | 19.8 (15.4–24.6) | 7.70 (6.72–8.81) | 1.59 | 0.207 |
| Stage IIIC | 13.4 (8.9–18.8) | – | – | – |
| T4bLNR5 (n=187) | 13.4 (8.9–18.8) | 9.76 (8.28–11.50) | 4.45§ | 0.035 |
†, log-rank tests were conducted between two sequential stages and twenty-one χ2 values were generated. All stages were compared with T1LNR1 as reference by values of HRs of Cox proportional hazards. ‡, log-rank tests were conducted between two sequential stages. §, HRs with 95% CIs were estimated using a Cox proportional hazards model, with T1LNR1 =0 as the reference in the training cohort. Twenty-five HR values were ordered from the lowest (T1LNR1) to the highest (T4bLNR5). Then, log-rank tests for 5-year overall survival were conducted between two sequential stages and 24 χ2 values were generated. Among the 24 χ2 values, six largest χ2 values were identified as the optimal cutoff values (5.79, 1.08, 6.36, 2.92, 4.05, 4.45), and we created seven categories of the TLNR classification that paralleled to those of the AJCC 7th and 8th TNM classifications. TLNR, T stage-lymph node ratio classification; 5-Y OS, 5-year overall survival; CI, confidence interval; HR, hazard ratio; LNR, lymph node ratio; No., number.