Table 1. Staging and Scoring System.
| Stage description | Description | Score |
|---|---|---|
| Primary tumor | ||
| T0 | No tumor | 1 |
| T1 | Small tumor (tumor d<7 mm) | 2 |
| T2 | Large tumor without infiltration (tumor d>7 mm) | 3 |
| T3 | Large tumor with infiltration but still visible margins | 4 |
| T4 | Diffuse and infiltrating tumor | 5 |
| Organ metastases | ||
| M0 | No liver or lung metastases | 1 |
| M1Li | Liver metastases | 5 |
| M1Lu | Lung metastases | 5 |
| M1 | Liver and lung metastases | 10 |
| Peritoneal metastases | ||
| P0 | No peritoneal metastases | 1 |
| P1 | Less than five peritoneal metastases or one with d<7 mm | 3 |
| P2 | More than five peritoneal metastases or one with d>7 mm | 4 |
| P3 | Malignant ascites | 5 |
| P4 | Diaphragm/kidney/intestine/adrenal metastases | 3+3+3+3+P0/1/2/3 |
| Lymph node metastases | ||
| N0 | No lymph node metastases | 1 |
| N1 | Peripancreatic lymph node metastases | 3 |
| N2 | Regional lymph node metastases (for example, mesenteric, mediastinal) | 5 |
Scores for the primary tumor (T), organ metastases (M) peritoneal metastases (P) and lymph node metastases (N) were multiplied to calculate the total tumor scores for each animal. Score P4 value is the sum of the corresponding P0, P1, P2, P3 (P0/1/2/3) plus an additional value of three for metastasis presence in the diaphragm, three for kidney, three for intestine and three for adrenal glands.