Collaborative Stage

Note 1: Ki-67 antigen is a nuclear protein, expressed by cells in all phases of the active cell cycle (G1,S, G2, and M phase) and absent in resting cells (G0 phase). Tumor cells with positive staining for Ki-67 antibodies are actively growing or proliferating. The fraction of Ki-67-positive tumor cells (the Ki-67 labeling index) may correlate with the clinical course of cancer. The value is expressed as the percentage of carcinoma cells in the tissue sample with positive staining for the Ki-67 protein.
Note 2: Record the percentage of Ki-67 growth fraction as expressed in the report. Do not calculate the percentage fraction.
Note 3: In the absence of a specific percentage value, code the percentage range as stated. Use codes 991-993 if the only expression is in terms of proliferation rate and both the percentage and percentage range are not available.

Code	Description
000-100	Percentage of Ki-67 growth fraction
110	Stated as Ki-67 growth fraction less than or equal to 5%
120	Stated as Ki-67 growth fraction greater than 5 % or less than or equal to 10%
130	Stated as Ki-67 growth fraction greater than 10% or less than or equal to 20%
140	Stated as Ki-67 growth fraction greater than 20% or less than or equal to 50%
150	Stated as Ki-67 growth fraction greater than 50%
888	OBSOLETE DATA CONVERTED V0200 See Code 988 Not applicable
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.)
991	Stated as low proliferation rate
992	Stated as increased proliferation rate
993	Stated as high proliferation rate
997	Ki-67 growth fraction study performed, results not available
998	Test not done, test was not ordered and was not performed
999	Unknown or no information Not documented in patient record

CS Site-Specific Factor 2
Ki-67 Labeling Index Lab Value