Table 3.
Inverse Probability Weighting Cox Proportional Hazards Regression of CSS for 187 Patients Who Received Lymph Node Dissection
| Characteristic | Variable | HR (95% CI) | P | Backward Selection HR (95% CI)a | Backward Selection Pa |
|---|---|---|---|---|---|
| Furhman grade | 4 | 1.34 (0.96, 1.87) | .08 | ||
| ≤3 | — | — | |||
| AJCC tumor stage | T3b | 0.79 (0.53, 1.17) | .24 | 0.76 (0.5, 1.16) | .21 |
| T3c | 1.35 (0.73, 2.50) | .34 | 1.47 (0.78, 2.78) | .23 | |
| T4 | 1.72 (1.03, 2.88) | .038b | 1.39 (0.80, 2.42) | .25 | |
| T3a | — | — | |||
| No. of nodes removed | 1.01 (0.99, 1.04) | .25 | |||
| No. of positive nodes | 1.10 (1.05, 1.14) | <.001b | 1.08 (1.03, 1.14) | .0009b | |
| Sarcomatoid features | Yes | 1.46 (0.98, 2.18) | .06 | — | |
| No | — | — | |||
| Rhabdoid features | Yes | 1.88 (0.90, 3.90) | .09 | — | |
| No | — | — | |||
| Tumor necrosis | 1 | 1.78 (1.21, 2.61) | .003b | — | |
| 2 | 0 | .99 | |||
| 0 | — | — | |||
| Soft tissue margin positive | 1 | 1.16 (0.80, 1.69) | .87 | — | |
| 0 | — | — | |||
| Systemic therapy | 1 | 1.16 (0.79, 1.69) | .44 | — | |
| 0 | — | — | |||
| No. of metastases | >1 | 1.21 (0.85, 1.71) | .29 | ||
| 1 | |||||
| MSKCC | Favorable | 1.15 (0.65, 1.57) | .52 | ||
| Intermediate | 1.58 (0.89, 2.33) | .06 | |||
| Poor | — | ||||
| Lymph node density | 2.29 (1.50, 3.48) | <.001b |
Variables included in model were grade, T stage, number of nodes removed, number of nodes positive, number of metastases, MSKCC category, and use of systemic therapy.
Abbreviations: AJCC = American Joint Committee on Cancer; CI = confidence interval; CSS = cancer-specific survival; HR = hazard ratio; MSKCC = Memorial Sloan Kettering Cancer Center.
a
Results from backward-selection multivariate Cox proportional hazards regression.
b
Statistically significant.