Collaborative Stage

Note 1: CS Site-Specific Factors 3-6 are used to code the presence or absence of lymph node involvement in each of 7 different levels and other groups defined by AJCC. The definitions of the levels are the same for all applicable head and neck sites. One digit is used to represent lymph nodes of a single level, with the digits of CS Site-Specific Factor 3 representing lymph nodes of Levels I-III; the digits of CS Site-Specific Factor 4 representing lymph nodes of Levels IV and V and the retropharyngeal nodes; the digits of CS Site-Specific Factor 5 representing lymph nodes of Levels VI and VII and the facial nodes; and the digits of CS Site-Specific Factor 6 representing the remaining Other groups as defined by AJCC. In each digit, a code 1 means yes, the nodes are involved.
Note 2: If involved regional node levels are documented as a range, or if the involved nodes overlap multiple levels, code all levels specified.
Note 3: If regional node(s) are known to be positive but the level of node(s) involved is unknown, use code 000.

Code	Description
000	No involvement in Levels IV or V or retropharyngeal lymph nodes
100	Level IV lymph node(s) involved
010	Level V lymph node(s) involved
001	Retropharyngeal nodes involved
110	Levels IV and V lymph nodes involved
101	Levels IV and retropharyngeal lymph nodes involved
011	Levels V and retropharyngeal lymph nodes involved
111	Levels IV and V and retropharyngeal lymph nodes involved
988	Not applicable: Information not collected for this case (If this item is required by your standard setter, use of code 988 will result in an edit error.)
999	Unknown if regional lymph nodes involved, not stated Regional lymph nodes cannot be assessed Not documented in patient record

CS Site-Specific Factor 4
Levels IV-V and Retropharyngeal Lymph Nodes for Head and Neck