ICD-10 Categories Not Used in ICD-O-3
As noted previously, the ICD-10 categories C00-C97 include a few categories that are either based on morphology or denote metastatic or secondary neoplasms which are described by the behavior code in ICD-O. Figure 5 shows the ICD-10 categories omitted from the topography section of ICD-O.
ICD-10 Equivalent ICD-O, Third Edition, Code
|C43||Melanoma of skin||C44._||M-872—M-879||/3|
|C81-C96||Malignant neoplasms of lymphoid, hematopoietic and related tissue||C00-C80||M-959-M-998||/3|
|C78||Secondary malignant neoplasms of respiratory and digestive systems||C15-C39||M-________||/6|
|C79||Secondary malignant neoplasms of other specified sites||C00-C14,
|D00-D09||In situ neoplasms||C00-C80||M-________||/2|
|D37-D48||Neoplasms of uncertain and unknown behavior||C00-C80||M-________||/1|
|C97||Malignant neoplasms of independent (primary) multiple sites||code each one||/3|
The C81-C96 section of ICD-10 is used for malignant neoplasms of lymphoid, hematopoietic and related tissues. In ICD-O, Third Edition, these are assigned specific morphology codes and the behavior code /3. The morphology code, combined with the appropriate topography code in the range C00-C80, expresses the complete diagnosis. For example, in ICD-10, lymphocytic lymphoma of the stomach is coded C83.0. In ICD-O, small cell (diffuse) non-Hodgkin lymphoma would be coded to stomach C16.9 and the morphology to M-9670/3 (diffuse small cell lymphoma).
The C97 category in ICD-10 is not included in ICD-O as each primary site is usually coded separately. Guidelines for determining what constitutes multiple primaries vary among countries. (See section on Multiple Primary Neoplasms)