Univariable and multivariable Cox regression analysis for locoregional recurrence-free survival at second recurrence
| Variable | Univariate | Multivariate | ||
| HR (95% CI) | P value | HR (95% CI) | P value | |
| Sex | ||||
| Female | 1 | 0.45 | ||
| Male | 1.46 (0.55 to 3.84) | |||
| Primary site | ||||
| Cutaneous | 1 | 0.082 | ||
| Other | 2.67 (0.88 to 8.09) | |||
| ECOG at first recurrence | ||||
| 0 | 1 | 0.84 | ||
| ≥1 | 1.12 (0.37 to 3.38) | |||
| LDH at first recurrence | ||||
| Normal (≤ULN) | 1 | 0.55 | ||
| Elevated (>ULN) | 1.82 (0.57 to 5.80) | |||
| Unknown | 0.95 (0.32 to 2.77) | |||
| Surgical margins first recurrence resection | ||||
| Involved | 1 | 0.38 | ||
| Clear | 2.48 (0.33 to 18.54) | |||
| Locoregional recurrence site | ||||
| LN only | 1 | 0.58 | ||
| ITM/satellites only | 1.67 (0.64 to 4.40) | |||
| Both LN+ITM | NA | |||
| ENE if LN involved: | ||||
| No | 1 | 0.39 | ||
| Yes | 0.48 (0.09 to 2.60) | |||
| Stage at first recurrence | ||||
| IIIB | 1 | 0.48 | ||
| IIIC | 3.50 (0.47 to 26.25) | |||
| IIID | NA | |||
| Recurrence detected by | ||||
| Symptoms | 1 | 0.76 | ||
| Clinical examination | 0.63 (0.17 to 2.30) | |||
| Imaging | 0.61 (0.15 to 2.45) | |||
| Adjuvant RT at first recurrence | ||||
| No | 1 | 0.031 | 1 | 0.015 |
| Yes | 0.20 (0.05 to 0.87) | 0.16 (0.04 to 0.70) | ||
| Adjuvant systemic therapy at first recurrence | ||||
| No drug | 1 | 1 | ||
| Same drug continued | 0.98 (0.28 to 3.48) | 0.84 | 0.56 (0.15 to 2.02) | 0.41 |
| New drug | 0.27 (0.09 to 0.85) | 0.029 | 0.21 (0.07 to 0.67) | 0.012 |
ECOG, Eastern Cooperative Oncology Group; ENE, extranodal extension ; ITM, in-transit metastases ; LDH, lactate dehydrogenase ; LN, lymph node; RT, radiotherapy; ULN, upper limit of normal.