Note 1: Use codes 000-009 only to report results of IHC on otherwise histologically negative lymph nodes on routine H and E stains., i.e., only when CS Lymph Nodes is coded 00. Otherwise code 888 in this field.
Note 2: Isolated tumor cells (ITC) are defined as single tumor cells or small clusters 0.2 mm, usually detected only by immunohistochemical (IHC) or molecular methods (RT-PCR: Reverse Transcriptase Polymerase Chain
Reaction) but which may be verified on H and E stains. ITCs do not usually show evidence of malignant activity (e.g., proliferation or stromal reaction.)
Note 3: If it is unstated whether or not IHC tests were done, assume they were not done.
|000||Regional lymph nodes negative on H and E, no IHC studies done or unknown if IHC studies done
Nodes clinically negative, not examined pathologically
|001||Regional lymph nodes negative on H and E, IHC studies done, negative for tumor|
|002||Regional lymph nodes negative on H and E, IHC studies done, positive for ITCs (tumor cell clusters not greater than 0.2mm)|
|009||Regional lymph nodes negative on H and E, positive for tumor detected by IHC, size of tumor cell clusters or metastases not stated|
CS Lymph Nodes not coded 00 or 05