Table 1

Paris staging system for primary gastrointestinal lymphomas*†

*Valid for lymphomas originating from the gastro-oesophageal junction to the anus (as defined by identical histomorphological structure).
†In case of more than one visible lesion synchronously originating in the gastrointestinal tract, give the characteristics of the more advanced lesion.
‡Anatomical designation of lymph nodes as “regional” according to site:
(a) stomach: perigastric nodes and those located along the ramifications of the coeliac artery (that is, left gastric artery, common hepatic artery, splenic artery) in accordance with compartments I and II of the Japanese Research Society for Gastric Cancer (1995);
(b) duodenum: pancreaticoduodenal, pyloric, hepatic, and superior mesenteric nodes;
(c) jejunum/ileum: mesenteric nodes and, for the terminal ileum only, the ileocolic as well as the posterior caecal nodes;
(d) colorectum: pericolic and perirectal nodes and those located along the ileocolic, right, middle, and left colic, inferior mesenteric, superior rectal, and internal iliac arteries.
TXLymphoma extent not specified
TONo evidence of lymphoma
T1Lymphoma confined to the mucosa/submucosa
T1mLymphoma confined to mucosa
T1smLymphoma confined to submucosa
T2Lymphoma infiltrates muscularis propria or subserosa
T3Lymphoma penetrates serosa (visceral peritoneum) without invasion of adjacent structures
T4Lymphoma invades adjacent structures or organs
NXInvolvement of lymph nodes not assessed
NONo evidence of lymph node involvement
N1‡Involvement of regional lymph nodes
N2Involvement of intra-abdominal lymph nodes beyond the regional area
N3Spread to extra-abdominal lymph nodes
MXDissemination of lymphoma not assessed
MONo evidence of extranodal dissemination
M1Non-continuous involvement of separate site in gastrointestinal tract (eg, stomach and rectum)
M2Non-continuous involvement of other tissues (eg, peritoneum, pleura) or organs (eg, tonsils, parotid gland, ocular adnexa, lung, liver, spleen, kidney, breast etc.)
BXInvolvement of bone marrow not assessed
B0No evidence of bone marrow involvement
B1Lymphomatous infiltration of bone marrow
TNMClinical staging: status of tumour, node, metastasis, bone marrow
pTNMBHistopathological staging: status of tumor, node, metastasis, bone marrow
pNThe histological examination will ordinarily include 6 or more lymph nodes