Table 3.
Paris staging system for primary gastrointestinal lymphomas
| Stage | Gastrointestinal lymphomas |
| TX | Lymphoma extent not specified |
| T0 | No evidence of lymphoma |
| T1 | Lymphoma confined to the mucosa/submucosa |
| T1m | Lymphoma confined to mucosa |
| T1sm | Lymphoma confined to submucosa |
| T2 | Lymphoma infiltrates muscularis propria or subserosa |
| T3 | Lymphoma penetrates serosa (visceral peritoneum) without invasion of adjacent structures |
| T4 | Lymphoma invades adjacent structures or organs |
| NX | Involvement of lymph nodes not assessed |
| N0 | No evidence of lymph node involvement |
| N1 | Involvement of regional lymph nodes |
| N2 | Involvement of intra-abdominal lymph nodes beyond the regional area |
| N3 | Spread to extra-abdominal lymph nodes |
| MX | Dissemination of lymphoma not assessed |
| M0 | No evidence of extranodal dissemination |
| M1 | Non-continuous involvement of separate site in gastrointestinal tract (e.g. stomach and rectum) |
| M2 | Non-continuous involvement of other tissues (e.g. peritoneum, pleura) or organs (e.g. tonsils, parotid gland, ocular, adnexa, lung, liver, spleen, kidney, breast, etc.) |
| BX | Involvement of bone marrow not assessed |
| B0 | No evidence of bone marrow involvement |
| B1 | Lymphomatous infiltration of bone marrow |
| TNM | Clinical staging: status of tumor, node, metastasis, bone marrow |
| pTNMB | Histopathological staging: status of tumor, node metastasis, bone marrow |
| pN | The histological examination will ordinarily include six or more lymph nodes |