Review: Coding Guidelines

Here is what we have learned from Coding Guidelines:

  • All neoplasms, whether malignant, benign, in situ, or uncertain whether benign or malignant, are coded with the same set of topography codes in ICD-O.
  • The topographic site of a neoplasm may be described by using the noun or its related adjective; in general, noun forms appear in the numerical list and alphabetic index of ICD-O.
  • If the diagnosis does not specify the tissue of origin, code the appropriate tissues suggested in the alphabetic index for each ill-defined site in preference to the "NOS" category.
  • If a topographic site is modified by a prefix such as peri-, para-, or the like, and is not specifically listed in ICD-O-3, code to the appropriate ill-defined subcategory C76 (ill-defined site), unless the type of tumor indicates origin from a particular tissue.
  • Use subcategory ".8" when a tumor overlaps the boundaries of two or more categories or subcategories and its point of origin cannot be determined.
  • If a lymphoma involves multiple lymph node regions, code to C77.8 (lymph nodes of multiple regions). Code extranodal lymphomas to the site of origin, which may not be the site of the biopsy. If no site is indicated for a lymphoma, code to C77.9 (lymph node, NOS).
  • Code all leukemias except myeloid sarcoma (M-9930/3) to C42.1 (bone marrow). Myeloid sarcoma is coded to the stated site of origin.
  • Use the appropriate 5th digit behavior code even if the exact term is not listed in ICD-O.
  • Assign the highest grade or differentiation code described in the diagnostic statement.
  • Use the topography code provided when a topographic site is not stated in the diagnosis. This topography code should be disregarded if the tumor is known to arise at another site.
  • Change the order of word roots in a compound term if the term is not listed in ICD-O.
  • When no single code includes all diagnostic terms, use the numerically higher code number if the diagnosis of a single tumor includes two modifying adjectives with different code numbers.
  • Most cancer registries collect data only on malignant and in situ neoplasms; behavior codes /6 and /9 are not generally used by cancer registries, but by pathologists or pathology departments.
  • In the use of the behavior code, pathologists are usually interested in "specimen coding" whereas the cancer registrar's main interest is identification of the primary tumor.