Collaborative Stage

Note 1: Since primary site codes C16.1 (fundus of stomach) and C16.2 (body of stomach) can be assigned to either schema, EsophagusGEJunction or Stomach, this schema discriminator field is needed for the CS Algorithm to determine which schema to select only when the site is C16.1 or C16.2.
Note 2: In 7th ed., Esophagogastric junction and the proximal 5 cm of the Stomach were removed from the Stomach schema and added to the Esophagus chapter. Due to differences in the schemas for Esophagus and Stomach, a new schema was created in CSv2 to accommodate these changes. In 7th ed., cancers whose midpoint is in the lower thoracic esophagus, esophagogastric junction, or within the proximal 5 cm of the stomach (cardia) that extend into the esophagogastric junction or esophagus are stage grouped similar to adenocarcinoma of the esophagus. All other cancers with a midpoint in the stomach greater than 5 cm distal to the esophagogastric junction, or those within 5 cm of the esophagogastric junction but not extending into the esophagogastric junction or esophagus, are stage grouped using the gastric cancer staging system.
Note 3: For cases coded to primary site code C16.1 or C16.2 and histology: 8000-8152,8154-8231,8243-8245,8247,8248,8250- 8934,8940-9136,9141-9582,9700-9701, code whether or not tumor extends to esophagus (crosses the EGJ) and code the stated distance of the midpoint of the tumor from the EGJ. This information will be used to determine whether the case has AJCC TNM and stage group assigned using definitions for esophagus or stomach cancers.
Note 4: If the primary site code is stomach and involvement of EGJ and distance from EGJ is unknown but a physician stages the case using esophagus definitions, assign to code 060. Collaborative Stage will use the EsophagusGEJunction schema to assign TNM and AJCC stage.

Code	Description	Schema
000	No involvement of esophagus or EGJ	Stomach
010	Tumor located in Cardia or EGJ	EsophagusGEJunction
020	Esophagus or EGJ involved AND distance of tumor midpoint from EGJ 5cm or less	EsophagusGEJunction
030	Esophagus or EGJ involved AND distance of tumor midpoint from EGJ more than 5cm	Stomach
040	Esophagus or EGJ involved AND distance of tumor midpoint from EGJ unknown	EsophagusGEJunction
050	Esophagus and EGJ not involved but distance of tumor midpoint from EGJ is 5cm or less	Stomach
060	Esophagus involved or esophagus involvement unknown AND distance of tumor midpoint from EGJ more than 5cm or unknown AND physician stages case using esophagus definitions	EsophagusGEJunction
100	OBSOLETE DATA RETAINED V0200 C16.1, C16.2 - originally coded in CSv1	Stomach
999	Involvement of esophagus not stated, unknown or no information, not documented in patient record	Stomach
	Blank for Stomach cases which are C16.3-C16.9	Stomach
	Blank for Cardia/EGJ cases which are C16.0	EsophagusGEJunction

Stomach

CS Site-Specific Factor 25Involvement of Cardia and Distance from Esophagogastric Junction (EGJ)

CS Site-Specific Factor 25
Involvement of Cardia and Distance from Esophagogastric Junction (EGJ)