Table 1.
Clinical and pathological characteristics of training and validation cohorts
| Clinical and pathological characteristics |
|||
|---|---|---|---|
| Training set | Validation set | ||
| Patients (n = 28) | Patients (n = 28) | ||
| Characteristics | No. (%) | No. (%) | P value |
| Age | |||
| Median (range) | 62.5 (48–77) | 63 (40–87) | 0.902 |
| Gradea | |||
| 1 | 11 (47.83) | 10 (38.46) | 0.925 |
| 2 | 9 (39.13) | 12 (46.15) | |
| 3 | 3 (13.04) | 4 (15.38) | |
| Gender | |||
| Male | 26 (92.86) | 26 (92.86) | 0.681 |
| Female | 2 (7.14) | 2 (7.14) | |
| Smoking | |||
| Yes | 23 (82.14) | 26 (92.86) | 0.197 |
| No | 5 (17.86) | 2 (7.14) | |
| Alcohol consumption | |||
| Yes | 15 (53.5) | 14 (50) | 0.449 |
| No | 13 (46.5) | 14 (50) | |
| Treatment modality | |||
| Surgery | 23 (82.1) | 24 (85.7) | 1.000 |
| Radiation therapy | 5 (17.9) | 4 (14.3) | |
| Disease-free survival (months) | |||
| Median (range) | 48 (1–148) | 59 (0–161) | 0.376 |
| Recurrence site | |||
| Primary site | 7 (25) | 7 (25) | 1.000 |
| Lymph nodes | 2 (7.14) | 1 (3.57) | |
| Distant site | 0 (0) | 0 (0) | |
Differences between patients of the training and validation sets were assessed using t-statistics for grade, gender, smoking status (defined as any smoking versus no smoking), treatment modality, recurrence site and alcohol consumption. Differences between patients of the training and validation sets were assessed using Mann–Whitney U test for age and disease-free survival. There was no statistically significant difference between training and validation sets in age, grade, gender, smoking status, alcohol consumption, treatment modality used and recurrence site or disease-free survival.
aGrade was not available for seven patients.