Collaborative Stage Data Set - Revised 04/19/2013 FINAL

MerkelCellSkin

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.

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