CS Site-Specific Factor 18

Isolated Tumor Cells (ITC) in Regional Lymph Node(s)


**Note 1**: Isolated tumor cells (ITCs) are defined as single tumor cells or small clusters not greater than 0.2 mm, usually detected by immunohistochemical (IHC) methods such as Cytokeratin 20 (CK20) or CAM 5.2 or pancytokeratins. For Merkel cell carcinoma, the presence of ITCs in regional lymph node(s) is considered as positive nodal involvement. **Note 2**: Record the status of ITCs as documented by the pathologist. **Note 3**: If regional lymph nodes are removed and are pathologically negative with no mention of ITC status, assume there are no ITCs and assign code 000. **Note 4**: Use code 999 if nodes are clinically involved but no pathologic examination of regional nodes is performed.




NAACCR #2872


Code Description
000 Regional lymph nodes negative on routine hematoxylin and eosin (H and E) stains, no immunohistochemical (IHC) studies for isolated tumor cells (ITC) done (CK20, CAM 5.2, pancytokeratins) or unknown if IHC studies done
Nodes clinically negative, not examined pathologically
010 Regional lymph nodes negative on routine H and E, IHC studies done (CK20, CAM5.2, pancytokeratins) and ITCs NOT PRESENT
020 Regional lymph nodes negative on routine H and E, IHC studies done (CK20, CAM 5.2, pancytokeratins) and ITCs PRESENT
090 Regional lymph nodes negative on routine H and E, positive for tumor detected by IHC, size of tumor cell clusters or metastases not stated
100 Regional lymph nodes positive with ITCs on routine H and E
200 Regional lymph nodes positive with ITCs, NOS, method of detection not stated
300 Regional lymph nodes positive other than ITCs
(Tumor cells greater than 0.2 millimeter (mm))
988 Not applicable: Information not collected for this case
(If this information is required by your standard setter, use of code 988 may result in an edit error.)
999 Unknown or no information
Not documented in pathology report or patient record
Clinical assessment of nodal involvement only