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General Rules

Coding CS Lymph Nodes

  1. Record the farthest specific regional lymph node chain that is involved by tumor either clinically or pathologically.
    1. Regional lymph nodes are listed for each site. The regional lymph nodes closest to the primary site have lower codes than nodes farther away. In addition, for some sites, regional lymph nodes are further classified by size, laterality, and number of involved nodes. Record the highest applicable code.
      Example: Peribronchial lymph nodes are positive on fine needle aspiration biopsy. Contralateral mediastinal mass noted on CT scan but not biopsied. Patient chooses radiation therapy as primary treatment.
      Use the code for contralateral mediastinal lymph node involvement as it is higher than the code for peribronchial lymph nodes.
    2. Record involved regional lymph nodes from the pathology report, if it is available, when the patient receives no radiation or systemic treatment prior to surgery.
    3. If there is a discrepancy between clinical information and pathologic information about the same lymph nodes, the pathologic information takes precedence.
      Example: Axillary lymphadenopathy stated as "suspicious for involvement" noted on physical exam. After axillary dissection, all lymph nodes are negative.
      Code CS Lymph Nodes as 0, no regional lymph node involvement.
    4. If there is direct extension of the primary tumor into a regional lymph node, record the involved node in this field.
    5. If the patient receives preoperative (neoadjuvant) systemic therapy (chemotherapy, hormone therapy, immunotherapy) or radiation therapy, code the farthest involved regional lymph nodes, whether this is based on information prior to surgery or following treatment.
  2. Use code 00 for lymph node involvement when the CS Extension is coded in situ, even if no lymph nodes are removed, since "in situ" by definition means noninvasive. If there is evidence of nodal involvement associated with a tumor described as in situ, it would indicate that an area of invasion was simply missed, and it is NOT an in situ lesion.
  3. For solid tumors, the terms "fixed" or "matted" and "mass in the hilum, mediastinum, retroperitoneum, and/or mesentery" (with no specific information as to tissue involved) are considered involvement of lymph nodes.
    1. Any other terms, such as "palpable," "enlarged," "visible swelling," "shotty," or "lymphadenopathy" should be ignored (except for adenopathy, enlargement, and mass in the hilum or mediastinum for lung primaries) unless there is a statement of involvement by the clinician.
    2. For lymphomas, any mention of lymph nodes is indicative of involvement.
    3. Regional lymph nodes are not palpable for inaccessible sites such as bladder, kidney, prostate, esophagus, stomach, lung, liver, corpus uteri and ovary. The best description concerning regional lymph nodes will be on imaging studies or the surgeon's evaluation at the time of exploratory surgery or definitive surgery. If regional lymph nodes for these inaccessible sites are not mentioned on imaging or exploratory surgery, they are presumed to be clinically negative.
    4. The terms "homolateral," "ipsilateral," and "same side" are used interchangeably.
    5. Any unidentified nodes included with the resected primary site specimen are to be coded as regional lymph nodes, NOS.
    6. Where more specific categories are provided, the codes for "regional lymph node(s), NOS" and "lymph nodes, NOS" should be used only after an exhaustive search for more specific information.
  4. When size of involved regional lymph nodes is required, code from pathology report, if given.
    1. Code the size of the metastasis, not the entire node, except as noted in site-specific instructions. The size of the metastasis within the lymph node can be inferred if the size for the entire node falls within one of the codes; for example a single involved node 1.5 cm in size can be coded to "single lymph node less than 2 cm" because the metastasis cannot be larger than 1.5 cm.
  5. If the only indication of lymph node involvement in the record is the physician's statement of an N category from the TNM staging system or a stage from a site-specific staging system, such as Dukes' C, record the numerically lowest equivalent CS lymph node code for that category.
    1. If there is a discrepancy between documentation in the medical record and the physician's assignment of TNM, the documentation takes precedence. Cases of this type should be discussed with the physician who assigned the TNM.
    2. If the information in the medical record is ambiguous or incomplete regarding the extent to which the tumor has spread, lymph node involvement may be inferred from the N category stated by the physician.
  6. For colon, rectosigmoid and rectum primaries, if there is a statement about tumor nodules(s) in the pericolic or perirectal fat, use the following guidelines for coding regional lymph node involvement: Code as regional lymph node involvement if the nodule is smooth contour.
    Code as tumor extension if the nodule has an irregular contour.