Table 5.
Lateral lymph node dissection and lateral lymph node metastasis of rectal cancer
| No. of patients | No. of patients who underwent lateral dissection | Prevalence of lateral dissection | No. of patients with lateral metastasis | Incidence of metastasis (percentage of all patients) | Incidence of lateral metastasis (percentage of patients who underwent lateral dissection) | |
|---|---|---|---|---|---|---|
| RS | ||||||
| sm | 124 | 0 | 0 | 0 | 0.0 | 0.0 |
| mp | 127 | 6 | 4.7 % | 0 | 0.0 | 0.0 |
| ss/a1 | 316 | 24 | 7.5 % | 0 | 0.0 | 0.0 |
| se/a2 | 177 | 8 | 4.5 % | 0 | 0.0 | 0.0 |
| si/ai | 32 | 14 | 43.8 % | 1 | 3.1 | 7.1 |
| Total | 776 | 52 | 6.7 % | 1 | 0.1 | 1.9 |
| Ra | ||||||
| sm | 138 | 5 | 3.6 % | 0 | 0.0 | 0.0 |
| mp | 149 | 18 | 12.1 % | 0 | 0.0 | 0.0 |
| ss/a1 | 230 | 58 | 25.2 % | 4 | 1.7 | 6.9 |
| se/a2 | 181 | 59 | 32.6 % | 7 | 3.9 | 11.9 |
| si/ai | 15 | 8 | 53.3 % | 0 | 0.0 | 0.0 |
| Total | 713 | 148 | 20.8 % | 11 | 1.5 | 7.4 |
| RaRb + Rb | ||||||
| sm | 234 | 37 | 15.8 % | 2 | 0.9 | 5.4 |
| mp | 372 | 218 | 58.6 % | 20 | 5.4 | 9.2 |
| ss/a1 | 350 | 230 | 65.7 % | 28 | 7.7 | 12.2 |
| se/a2 | 412 | 319 | 77.4 % | 75 | 18.0 | 23.5 |
| si/ai | 59 | 48 | 81.4 % | 17 | 28.8 | 35.4 |
| Total | 1,427 | 852 | 59.7 % | 142 | 9.8 | 16.7 |
(Project study by the JSCCR: patients in years 1991–1998)