Table 3. False-negative rate and sensitivity of frozen section of sentinel lymph node by related pathological factors.
| Variables | N° (%) | TP | FN | Se % | FNR % | p Value |
|---|---|---|---|---|---|---|
| Total | 281 (100) | 58 | 18 | 76.3 | 23.7 | – |
| SLN metastasis size | ||||||
| Micrometastasis | 15 (19.7) | 5 | 10 | 33.3 | 66.7 | < 0.001 |
| Macrometastasis | 61 (80.3) | 53 | 8 | 86.9 | 13.1 | |
| Number of SLNs dissected | ||||||
| ≤ 2 | 50 (65.8) | 42 | 8 | 84.0 | 16.0 | 0.029 |
| > 2 | 26 (34.2) | 16 | 10 | 61.5 | 38.5 | |
| Tumour size | ||||||
| ≤ 2 cm | 37 (48.7) | 29 | 8 | 78.4 | 21.6 | 0.680 |
| > 2 cm | 39 (51.3) | 29 | 10 | 74.4 | 25.6 | |
| Lymphovascular involvement | ||||||
| Absent | 29 (38.2) | 22 | 7 | 75.9 | 24.1 | 0.942 |
| Present | 47 (61.8) | 36 | 11 | 76.6 | 23.4 | |
| Multicentricity | ||||||
| Absent | 68 (89.5) | 52 | 16 | 76.5 | 23.5 | 0.926 |
| Present | 8 (10.5) | 6 | 2 | 75.0 | 25.0 | |
Bold values represent statistical significance. TP: true positives, FN: false negatives, Se: sensitivity, FNR: false-negative rate, SLN: sentinel lymph node