Collaborative Stage

Note 1: Record the pathologic response to preoperative adjuvant treatment as documented in the pathology report. The response may be called "treatment effect" and will often be stated in terms of a Tumor Regression Grade of 0 to 3. The response may also be characterized in descriptive terms. Consult the pathologist if a different grading system is used.
Note 2: Tumor regression grade or treatment effect should only be assessed on the primary tumor.
Note 3: If a response is stated to be present or found but is not described further, use code 990.

Code	Description
000	Tumor Regression Grade 0 Complete response: No viable cancer cells No residual tumor
010	Tumor Regression Grade 1 Moderate response: Single cells or small groups of cancer cells
020	Tumor Regression Grade 2 Minimal response: Residual cancer outgrown by fibrosis
030	Tumor Regression Grade 3 Poor response: Minimal or no tumor kill; extensive residual cancer
888	OBSOLETE DATA CONVERTED V0200 See code 988 Not applicable for this site.
988	Not applicable: Information not collected for this case (May include cases converted from code 888 used in CSv1 for "Not applicable" or when the item was not collected. If this item is required to derive T, N, M, or any stage, use of code 988 may result in an error.)
990	Response present, but degree of response not further described
998	No preoperative treatment or no resection of primary site after preoperative treatment
999	Unknown or no information Not documented in patient record

CS Site-Specific Factor 5
Tumor Regression Grade