pTNM Stage Group

Field Length:  4

This field identifies the anatomic extent of disease based on the T, N, and M elements known following the completion of surgical therapy.  Code the pathologic TNM stage grouping from the pTNM classification in items 31010-31030, using the AJCC Cancer Staging Manual.  Record '88' if the site/histology does not have a TNM staging scheme. Choose the lower (less advanced) stage grouping when there is any uncertainty.

Note: For diagnoses prior to 2004, this field was used to calculate Best Stage Group. It becomes the Best Stage, unless the value is '88' or '99,’ or pre-surgical treatment was administered.  After 2004, the CS derived AJCC 6th edition stage group is the Best Stage Group.