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Need for mapping of SNOMED RT to SNOMED CT

Dear community members,

We work for an accreditated SME (P.G.M.D. Consulting) involved in the EHDEN Project and we are currently mapping the records coming from anatomic pathology examinations carried out in some Italian laboratories.

These examinations are coded through 3 different fields, identifying respectively topography, morphology and procedure. These fields are coded according to SNOMED-RT (an example of a morphology code is “M-44020”, corresponding to “Pyogenic granuloma”; similar codes, but starting with the letters “T” and “P” are assigned to topography and procedure), and we can’t seem to find the correspondence between this vocabulary and SNOMED-CT in Athena.

Unfortunately, SNOMED does not release previous versions of the vocabulary, unless for scientific reasons, therefore we would like to ask you if you have a correspondence table that you can share with us. These table appears to have been released when the conversion between SNOMET-RT and SNOMED-CT occurred (see pages 224 and following of the link (https://confluence.ihtsdotools.org/download/attachments/73368648/doc_RF1Guide_Current-en-US_INT_20140731.pdf)).

We are looking forward to your feedbacks.

Best regards



Oh boy. SNOMED RT? That thing died 20 years ago. I am sure there is some conversion table somewhere, but I am surprised it is still in use. Happy to ask your SNOMED friends to find out.


If you are working on UK data, you can probably register with the NHS / TRUD and get it from there.


Tell us if that works for you!

Dear Michael,
Thank you for your suggestion. Unfortunately we have subscribed to the link that you sent us, but there are no releases for the mapping table that you suggested. We searched for other releases from the same website but we couldn’t manage to find any alternative. Would you have any other suggestion for us?
Thank you very much for your help.

Best regards

Dear @Matteo , I have reached out to a contact in SNOMED, but cannot promise anything. I didn’t notice the Releases (0) indication…
thanks - Mik

Dear @mik ,
Thank so much for your help, we look forward to hearing from you.