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SEER Training Modules

General Rules

Coding CS Metastasis Evaluation

  1. Refer to general guidelines for Collaborative Staging regarding timing rules for data collection.
  2. Refer to site-specific instructions for additional information. Site-specific instructions replace or override general instructions. Where there are no site-specific instructions, general instructions apply.
  3. Record tumor size information in the following order:
    1. Record tumor size from the pathology report, if it is available, when the patient receives no radiation or systemic treatment prior to surgery.
      Example: Chest x-ray shows 3.5 cm mass; the pathology report from the surgery states that the same mass is malignant and measures 2.8 cm. Record tumor size as 028.
    2. If the patient receives pre-operative (neoadjuvant) systemic therapy (chemotherapy, hormone therapy, immunotherapy) or radiation therapy, code the largest tumor size whether prior to or following treatment.
      Example: Patient has a 2.2 cm mass in the oropharynx; fine needle aspiration of mass confirms squamous cell carcinoma. Patient receives course of neoadjuvant combination chemotherapy. Pathologic size of tumor after total resection is 0.8 cm. Record tumor size as 022.
    3. Information on size from imaging/radiographic techniques can be used to code size when there is no more specific size information from a pathology or operative report, but it should be taken as low priority, just above a physical exam.
    4. If there is a difference in reported tumor size among imaging and radiographic techniques, record the largest tumor size reported in the record.
  4. Record the exact size of the primary tumor for all sites except those for which it is stated to be not applicable. If no size is given, code as 999.
    1. Always code the size of the primary tumor, not the size of the polyp, ulcer, cyst, or distant metastasis. However, if the tumor is described as a "cystic mass," and only the size of the entire mass is given, code the size of the entire mass, since the cysts are part of the tumor itself.
    2. Record the largest dimension or diameter of tumor, whether it is from an excisional biopsy specimen or the complete resection of the primary tumor.
      Example: A 3.3 cm tumor would be 33 millimeters and would be coded as 033.
      Example: Tumor is described as 2.4 x 5.1 x 1.8 cm in size. Record tumor size as 051.
    3. Record the size of the invasive component, if given.
    4. If both an in situ and an invasive component are present, and the invasive component is measured, record the size of the invasive component even if it is smaller.
      Example: Tumor is mixed in situ and invasive adenocarcinoma, total 3.7 cm in size, of which 1.4 cm is invasive. Record tumor size as 014.
    5. Additional rule for breast primaries: If the size of the invasive component is not given, record the size of the entire tumor from the surgical report, pathology report, radiology report or clinical examination.
      Example: Infiltrating duct carcinoma with extensive in situ component; total size 2.3 cm. Record tumor size as 023.
      Example: Duct carcinoma in situ covering a 1.9 cm area with focal areas of invasive ductal carcinoma. Record tumor size as 019. Note: For breast cancer, document how the size of the tumor was determined in Site Specific Factor field 6.
    6. For in situ lesions, code the size as stated.
    7. Microscopic residual tumor does not affect overall tumor size.
    8. Do not add pieces or chips together to create a whole; they may not be from the same location, or they may represent only a very small portion of a large tumor.
    9. If an excisional biopsy is performed and residual tumor at time of resection of the primary is found to be larger than the excisional biopsy, code the size of the residual tumor.
    10. For an incisional needle biopsy, code tumor size as 999. Do not code the tumor size from a needle biopsy unless there is no residual tumor found on further resection.
    11. Record tumor size (lateral dimension) for malignant melanoma. Depth of invasion will be coded in a site-specific factor.
  5. Special codes
    1. Tumor dimension is to be recorded for all primary sites, except as noted below. Other information previously collected in this field in other staging systems, such as depth of invasion for melanoma, has been moved to the Site-Specific Factors for those sites.
    2. If size is not reported, code as 999, which means unknown size, not applicable, or not documented in the patient record.
    3. The descriptions in code 998 take precedence over any mention of size. Code 998 is used only for the following sites:
      • Esophagus (C15.0-C15.5, C15.8-C15.9): Entire circumference.
      • Stomach (C16.0-C16.6, C16.8-C16.9): Diffuse, widespread—¾ or more, linitis plastica.
      • Colorectal (M-8220/8221 with /2 or /3): Familial/multiple polyposis.
      • Lung and main stem bronchus (C34.0-C34.3, C34.8-C34.9): Diffuse, entire lobe or lung.
      • Breast (C50.0-C50.6, C50.8-C50.9): Inflammatory carcinoma; Diffuse, widespread—¾ or more of breast.
    4. Code 990, Microscopic focus or foci only; no size is given, should be used when no gross tumor is seen and tumor is only identified microscopically.
      Note: the terms microscopic focus, microfocus, and microinvasion are NOT the same as macroscopic focal or focus. A macroscopic focus or foci indicates a very small or isolated area or pinpoint or spot of tumor that may be visible grossly.
      Example: Cervix conization: severe dysplasia with focal areas of microinvasion. Code tumor size as 990 microscopic focus, no size given.
    5. Codes 991 through 995 are non-specific size descriptions which for some sites could still be used to determine a T category. If a specific size is given, code the more precise size in the range 001- 989.
    6. Other special codes in the range 996 to 997 are used on a site-specific basis. Refer to the individual site schemes for further information and definitions.
      Note: For the following diagnoses and/or primary sites, size is not applicable. Record as code 999.
      • Hematopoietic neoplasms, Immunoproliferative diseases, and Disseminated Langerhans cell histiocytosis (Letterer-Siwe disease).
      • Malignant lymphoma (Hodgkin lymphoma and non-Hodgkin lymphoma)
      • Leukemia, Multiple myeloma, and other plasma cell tumors
      • Mast cell tumors, Myeloproliferative diseases Myelodysplastic syndromes, Unknown and ill-defined primary sites (C76.0-76.5, C76.7-76.8, C80.9, C42._ and C77._)
    7. The source of the tumor size (radiographs, endoscopy, pathology specimen, etc.) is documented in the TS/Ext Eval field.