Japanese classification of gastric carcinoma: 3rd …

1 special ARTICLEJ apanese classification of gastric carcinoma : 3rd English editionJapanese gastric Cancer AssociationPublished online: 15 May 2011 The International gastric Cancer Association and The Japanese gastric Cancer Association 20111 General principlesGastric cancer findings are categorized and recorded usingthe upper case letters T, H, etc. The extent of disease foreach parameter is expressed by Arabic numerals followingthe letter ( , T3 H1); where the extent of disease isunknown, X is used. The clinical and pathological classi-fications are derived from information acquired from var-ious clinical, imaging, and pathological sources (listed inTable1). The clinical classification (c) is derived at theconclusion of pretreatment assessment before a decision ismade regarding the appropriateness of surgery. This clas-sification is an essential guide to treatment selection andenables the evaluation of therapeutic options.

2 The patho-logical classification (p) is based on the clinical classifi-cation supplemented or modified by additional evidenceacquired from pathological examination. This informsdecision-making regarding additional therapy and providesprognostic information. Where there is doubt regarding theT, N, or M category, the less advanced category should tumor findings are recorded in the follow-ing order: tumor location, macroscopic type, size, histo-logical type, depth of invasion, cancer stroma relationship,pattern of infiltration, lymphatic invasion, venous invasion,lymph node metastasis, and resection margins. For exam-ple: L, Less, Type 2, 50920 mm, tub1[tub2, pT2, int,INFb, ly1, v1, pN1 (2/13), pPM0, pDM0 (see subsequenttext for an explanation of the abbreviations).2 Anatomical extent and stage of gastric Description of the primary Size and number of lesionsThe two greatest dimensions should be recorded for eachlesion.]

3 Where there are multiple lesions, the tumor with themost advanced T category (or the largest lesion where theT stage is identical) is Tumor The three gastric regions and the esophagogastricjunctionThe stomach is anatomically divided into threeportions, the upper (U), middle (M), and lower (L) parts, bythe lines connecting the trisected points on the lesser andgreater curvatures ( ). gastric tumors are described bythe parts involved. If more than one part is involved, allinvolved portions should be recorded in descending orderof degree of involvement, with the part containing thebulk of tumor first, , LM or UML. Tumor extensioninto the esophagus or duodenum is recorded as E or D, online version of the prefatory article referred to in this articlecan be found under edition editors: Takeshi Sano (&), Yasuhiro : gastric Cancer Association (&)Association office, First Department of Surgery,Kyoto Prefectural University of Medicine,Kawaramachi, Kamigyo-ku, Kyoto 602-0841, Japane-mail: Cancer (2011) 14:101 112 DOI area extending 2 cm above to 2 cm below theesophagogastric junction (EGJ) is designated the EGJ having their epicenter in this area are designatedEGJ carcinomas irrespective of histological type.

4 Thelocation of an EGJ carcinoma is described using the sym-bols E (proximal 2 cm segment) and G (distal 2 cm seg-ment), with the dominant area of invasion described first, , E, EG, E=G (both areas equally involved), GE, or distance between the tumor center and the EGJ EGJ is defined as the border between the esophagealand gastric muscles. Clinically this is identified by one ofthe following: (a) the distal end of the longitudinal pali-sading small vessels in the lower esophagus at endoscopy;(b) the horizontal level of the angle of His shown by bar-ium meal examination; (c) the proximal end of the longi-tudinal folds of the greater curve of the stomach shown atendoscopy or barium meal study; or (d) the level of themacroscopic caliber change of the resected esophagus andstomach. It is important to note that the squamocolumnarjunction (SCJ) does not always coincide with the , the tumor location is often expressed ascardia, fundus, body, incisura, and Cross-sectional parts of the stomachThe stom-ach s cross-sectional circumference is divided into fourequal parts: the lesser (Less) and greater (Gre) curvatures,and the anterior (Ant) and posterior (Post) walls ( ).

5 Circumferential involvement is recorded as carcinoma in the remnant stomachCarcinoma inthe remnant stomach encompasses all carcinomas arising inthe remnant stomach following a gastrectomy, irrespective ofthe histology of the primary lesion (benign or malignant) or itsrisk of recurrence, the extent of resection, or method ofreconstruction. The following information should be recorded,as well as, if available, information on the extent of resectionand type of reconstruction of the previous primary lesion at the previous gastrectomy: benign(B), malignant (M), or unknown (X). time interval elapsed between the previous gastrec-tomy and the current diagnosis, in years (unknown: X). location in the remnant stomach: anastomoticsite (A), gastric suture line (S), other gastric site (O), ortotal remnant stomach (T). Extension into the esoph-agus (E), duodenum (D), or jejunum (J) is : B-20-S, Macroscopic Basic classificationGross tumor morphology iscategorized as either superficial or advanced type.

6 Super-ficial type is typical of T1 tumors while T2 4 tumorsusually manifest as advanced types ( ). Viewed fromthe mucosal surface, gross tumor appearance is categorizedinto six types (Table2). Type 0 is subdivided according tothe Macroscopic Classification of Early gastric Cancer( ). Although macroscopic type is determinedregardless of the depth of tumor invasion, the T categoryshould also be Subclassification of Type 0 ( , modified from theJapanese Endoscopy Society Classification of 1962)Super-ficial tumors with two or more components should have allcomponents recorded in order of the surface area occupied, 0-IIc?III (Table3). Description of macroscopic typeThe macro-scopic tumor type should be recorded in both the clinicaland pathological 1 The three portions of the third,Mmiddlethird,Llower third,Eesophagus,DduodenumFig. 2 The four equal parts of the gastric ,Gregreater curvature,Antanterior wall,Postposterior wallTable 1 Clinical and pathological classificationClinical classification (c)Pathological classification (c)Physical examination, imagingstudies, endoscopic, laparoscopicand surgical findings, biopsy,cytology, biochemical andbiological examination ofsurgically or endoscopicallyresected specimens; peritoneallavage gastric Cancer Histological classification (Table4)Where a malignant epithelial tumor consists of more thanone histological subtype, the different histological com-ponents should be recorded in descending order of thesurface area occupied, , tub 1[pap (see table below).]

7 Depth of tumor invasion (T)The depth of tumor invasion is recorded as the characters denoting depth of tumor invasionare also recorded: M, SM, MP, SS, SE, SI (see below). Theprefixes c and p are used in conjunction with theT-category and not with the characters M, SM, etc. ( , apathologically diagnosed mucosal tumor should be recor-ded as pT1a, not pM). Tumor invasion into the muscularismucosa is included in the M category. Early gastric cancercomprises of T1 tumors irrespective of lymph of tumor unknownT0No evidence of primary tumorT1 Tumor confined to the mucosa (M) or submucosa(SM)T1aTumor confined to the mucosa (M)T1bTumor confined to the submucosa (SM)1T2 Tumor invades the muscularis propria (MP)Table 3 Subclassification of Type 0 Type 0-I (protruding)aPolypoid 0-II (superficial)Tumors with or without minimal elevation ordepression relative to the 0-IIa(superficial elevated)aSlightly elevated 0-IIb(superficial flat)Tumors without elevation or 0-IIc(superficial depressed)Slightly depressed 0-III (excavated)Tumors with deep with less than 3mm elevation are usually classified as 0-IIa, withmore elevated tumors being classified as 0-IType 1 MassType 2 UlcerativeType 3 Infiltrative ulcerativeType 4 Diffuse infiltrativeFig.

8 3 Macroscopic types of advanced gastric cancerTable 2 Macroscopic typesType 0 (superficial) Typical of T1 1 (mass)Polypoid tumors, sharply demarcated from thesurrounding 2 (ulcerative)Ulcerated tumors with raised marginssurrounded by a thickened gastric wall withclear 3 (infiltrativeulcerative)Ulcerated tumors with raised margins,surrounded by a thickened gastric wallwithout clear 4 (diffuseinfiltrative)Tumors without marked ulceration or raisedmargins, the gastric wall is thickened andindurated and the margin is 5(unclassifiable)Tumors that cannot be classified into any of theabove 0-IProtrudingType 0-IISuperficialType 0-IIIE xcavatedType 0 Superficial, flatType 0-IIaSup. elevatedType 0-IIbSup. flatType 0-IIcSup. depressedFig. 4 Subclassification of Type 01SM may be subclassified as SM1 or T1b1 (tumor invasion is mm of the muscularis mucosae) or SM2 or T1b2 (tumor invasionis mm or more deep into the muscularis mucosae).

9 Japanese classification of gastric carcinoma103123 Table 4 Histological classification of gastric tumorsBenign epithelial tumorICD-O codeAdenoma8140/0 Malignant epithelial tumorCommon typePapillary adenocarcinoma (pap)8260/3 Tubular adenocarcinoma (tub)8211/3 Well-differentiated (tub1)Moderately differentiated (tub2)Poorly differentiated adenocarcinoma (por)Solid type (por1)Non-solid type (por2)Signet-ring cell carcinoma (sig)8490/3 Mucinous adenocarcinoma (muc)8489/3 special typeCarcinoid tumor8240/3 Endocrine carcinoma8401/3 carcinoma with lymphoid stromaHepatoid adenocarcinomaAdenosquamous carcinoma8560/3 Squamous cell carcinoma8070/3 Undifferentiated carcinoma8020/3 Miscellaneous carcinomaNon-epithelial tumorGastrointestinal stromal tumor (GIST)8396/0,1,3 Smooth muscle tumor8890/0,3 Neurogenic tumor9560/9580/0 Miscellaneous non-epithelial tumorsLymphomaB-cell lymphomaMALT (mucosa-associatedlymphoid tissue) lymphoma9699/3 Follicular lymphoma9690/3 Mantle cell lymphoma9673/3 Diffuse large B-cell lymphoma9680/3 Other B-cell lymphomasT-cell lymphomaOther lymphomasMetastatic tumorTumor-like lesionHyperplastic polypFundic gland polypHeterotopic submucosal glandHeterotopic pancreasInflammatory fibroid polyp (IFP)

10 Gastrointestinal polyposisFamilial polyposis coli, Peutz Jegherssyndrome, juvenile polyposis,Cowden s diseaseOthersTable 5 Anatomical definitions of lymph node paracardial LNs, including those along the first branch ofthe ascending limb of the left gastric paracardial LNs including those along theesophagocardiac branch of the left subphrenic artery3aLesser curvature LNs along the branches of the left gastricartery3bLesser curvature LNs along the 2nd branch and distal part ofthe right gastric artery4saLeft greater curvature LNs along the short gastric arteries(perigastric area)4sbLeft greater curvature LNs along the left gastroepiploic artery(perigastric area)4dRt. greater curvature LNs along the 2nd branch and distal partof the right gastroepiploic artery5 Suprapyloric LNs along the 1st branch and proximal part of theright gastric artery6 Infrapyloric LNs along the first branch and proximal part of theright gastroepiploic artery down to the confluence of the rightgastroepiploic vein and the anterior superiorpancreatoduodenal vein7 LNs along the trunk of left gastric artery between its root andthe origin of its ascending branch8aAnterosuperior LNs along the common hepatic artery8pPosterior LNs along the common hepatic artery9 Celiac artery LNs10 Splenic hilar LNs including those adjacent to the splenic arterydistal to the pancreatic tail.