Collaborative Stage

Note 1: Use codes 000-002 only to report results of molecular studies (RT-PCR: Reverse Transcriptase Polymerase Chain Reaction) on otherwise histologically negative lymph nodes on routine H and E stains, i.e., only when CS Lymph Nodes is coded 000. Otherwise code 987 in this field.
Note 2: Isolated tumor cells (ITC) are defined as single tumor cells or small clusters not greater than 0.2 mm, detected by immunohistochemical (IHC) (see CS Site_Specific Factor 4) or by H and E (CS Lymph Nodes code 050) or molecular methods (RT-PCR: Reverse Transcriptase Polymerase Chain Reaction). ITCs do not usually show evidence of malignant activity (e.g., proliferation or stromal reaction.)
Note 3: If it is not stated whether molecular tests were done, assume they were not done.

Code	Description
000	Regional lymph nodes negative on H and E, no RT-PCR molecular studies done or unknown if RT-PCR studies done Nodes clinically negative, not examined pathologically
001	Regional lymph nodes negative on H and E, RT-PCR molecular studies done, negative for tumor
002	Regional lymph nodes negative on H and E, RT-PCR molecular studies done, positive for tumor
888	OBSOLETE DATA CONVERTED V0200 See code 987 Not applicable CS Lymph Nodes not coded 000
987	Not applicable CS Lymph Nodes not coded 000

CS Site-Specific Factor 5
Molecular Studies of Regional Lymph Nodes