California Cancer Reporting System Standards Volume I: Abstracting and Coding Procedures for Hospitals
If a cancer continues to grow after the onset of local invasion, the regional lymph nodes draining the area usually become involved at some point. Enter code 3 if nodal involvement is indicated but there is no other evidence of extension beyond the organ of origin. Words like "local" and "metastasis" appearing in medical records sometimes cause confusion in coding this stage. Failure to recognize the names of regional lymph nodes might lead to incorrect staging. The Summary Staging Guide and the American Joint Committee on Cancer's Manual for Staging of Cancer (see Section I.1.6.5) contain helpful information about the names of nodes.
Diagnoses such as "carcinoma of the stomach with involvement of the local lymph nodes" should, lacking further evidence, be considered regional and staged as code 3.
Statements like "carcinoma of the breast with auxiliary lymph node metastasis" and "carcinoma of the stomach with metastasis to perigastric nodes" indicate metastasis to regional nodes and should be staged as code 3.