ICD-O-4 (Update as of January 25, 2021)
With the new 5th edition of the Blue Books commencing (it will be completed by mid-2023), it is now the time for the IARC WHO Classification of Tumours Group to start creating new codes. Due to the lack of available codes for new morphological diagnoses in the current 4-digit morphology structure, it is proposed for the next ICD-O edition (ICD-O-4) that a 5th digit will be added.
This approach, with the addition of a “0” where there is no need for a more specific code, or other values if needed was chosen for the ease of conversion and consistency with ICD-O-3 (similar to a MOTNAC to ICD-O-1 conversion). Adding an additional digit to the existing four retains the needed consistency, including the possibility to collapse to previous versions, but will likely require minor changes in registry software, notification forms, etc.
As the previous IACR ICD-O Working Group has now concluded its work with ICD-O-3.2, IACR will establish a new WG with global representation, with a terms of reference that focuses on the required planning for the implementation of ICD-O-4 in cancer registries worldwide.
ICD-O-3.2 (Update as of January 25, 2021):
The preparation of ICD-O-3.2 book (pdf) is at its final stages at the WHO Press, and we hope to have it in the first half of 2021. In the meantime, please refer to the tables available in this page.
Please read through our page on the International Classification of Diseases for Oncology (ICD-O) for details and updates of ICD-O-3.2 and the work that will start for ICD-O-4:
