Best Stage Group

Field Length: 2

This is a field calculated by the computer. It does not appear on the Abstract Form. However, it is available for analysis and reporting purposes. It is calculated from the CS derived stage or the pathologic and clinical TNM Stage Groups recorded for this case. For cases diagnosed from 1/1/2004 through 12/31/2017, the Best Stage Group is the CS derived AJCC 6 stage group.  For cases diagnosed prior to 1/1/2004, the value in this field is equal to the pTNM Stage Group, unless that value is '88' or '99' or there was pre-operative treatment (p Descriptor is 'Y'). Then it is equal to the value in the cTNM Stage Group. For case diagnosed 01/01/2018 and forward see 2018 Best Stage Group.