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COVID-19 Content

Content relating to COVID-19 can be viewed here SNOMED CT COVID-19 Related Content

July 2021 International Release and future releases

Browse Content Changes for the July 2021 Release

The daily build is available to review changes made to content for the July 2021 release https://dailybuild.ihtsdotools.org/

Forthcoming concept inactivations, new concepts and changes to existing concepts can be reviewed using the tab 'Daily build.'

Implementation of the new anatomy concept model

The completion of the revision of hierarchical relationships provides stable anatomy content and improves the quality of classification results in other hierarchies.

Over forthcoming releases, the plan is to implement the new anatomy concept model. There are almost 35,000 anatomy concepts and they will be modeled by different types of 'part of' relationships. The new model will enable us to automatically generate hierarchies to further improve quality and consistency. 

Information about the work completed in previous release for revision of IS_A relationships can be viewed here: https://confluence.ihtsdotools.org/display/IAP/Revision+of+IS-A+relationships+for+anatomy

July 2021 International Release and future releases

MRCM Changes

Please check here for further details MRCM changes in the July 2021 release

Quality Initiative

Information about the project can found here - Quality Initiative - Progress

Note: There are changes to the Service Level Agreement for the CRS as a result of the Quality Initiative:

https://www.snomed.org/SNOMED/media/SNOMED/documents/Changes-to-SLA_202005_MHA.pdf

Breeds

There are >3000 concepts in the organism hierarchy related to various breeds.

These concepts will be inactivated from the International release and moved to the veterinary extension. Based on the editorial guidelines, breeds are restricted to the veterinary domain. 

Inactivation and replacement of neoplastic morphology concepts containing ICD-O-3 classification terming

Some ICD-O version 3 morphology classification codes include Not Otherwise Specified (NOS), these concepts are not acceptable in SNOMED CT as per Editorial Guidance and are not meaningful outside of the ICD-O classification context.

In the current 400177003 |Neoplasm and/or hamartoma (morphologic abnormality)| sub-hierarchy there are approximately 75 neoplastic morphology concepts containing  the terming "no International Classification of Diseases for Oncology subtype (morphologic abnormality)" and/or "no ICD-O subtype" originating from ICD-O-3 and they are utilized in the modeling of about 460 disorders in the 55342001 |Neoplastic disease (disorder)| hierarchy.

• The concepts "no International Classification of Diseases for Oncology subtype (morphologic abnormality)" and/or "no ICD-O subtype" will be inactivated with reason Outdated (pending the development of a specific inactivation reason for classification schema entities) and replaced with either a new concept or an existing suitable target concept. This work will be carried out in liaison with the Cancer Synoptic Reporting Clinical Project Group.
  • For example:18365006 |Adrenal cortical adenoma, no International Classification of Diseases for Oncology subtype (morphologic abnormality)| has been inactivated and replaced with 1156661006 |Adrenal cortical adenoma (morphologic abnormality)|. 
• Review and remodel of the neoplasm disorder concepts that utilize these morphologies. 
• Identify those neoplastic morphologic abnormalities in SNOMED CT which have non-synonymous descriptions originating from ICD-O-3. Inactivate these descriptions as non-semantically equivalent and recreate them as new subtype or sibling concept including remodel of relevant disorder concepts. 

Inactivation of 250171008 |Clinical history and observation findings (finding)|

The primitive concept 250171008 |Clinical history and observation findings (finding)| is to be inactivated for the July 2021 release.

Inactivation of Content - Overdose/ Poisoning of undetermined intent

The Editorial Advisory Group (EAG) has recommended inactivation of concepts which refer to overdose or poisoning of undetermined intent because it is unclear what “undetermined intent” means (e.g. not asked, refused to answer, unable to answer).

Concepts which refer to overdose or poisoning of undetermined intent will be inactivated for the July 2021 International Release with a reason of Duplicate with a historical relationship to the unspecified parent.

We are also reviewing and updating the modeling for concepts in the poisoning and overdose sub-hierarchies for compliance with newly constructed templates based on feedback from the Editorial Advisory Group.

As part of this review, we are identifying and inactivating concepts that are ambiguous or that are not clinically useful.  The list of inactivated concepts can be tracked via daily build https://dailybuild.ihtsdotools.org/

Cancer Synoptic Reporting

Concepts representing cancer synoptic reporting content will be added to the International release starting with the July 2021 release. 

Cancer synoptic reports are used by many member countries to record pathology examination of cancer specimens including the College of American Pathologists (US and Canada), Royal College of Pathology (UK), Royal College of Pathology Australasia (Australia, New Zealand), PALGA (The Netherlands), Swedish Society of Pathology, and others.

This content primarily encompasses observable entity concepts and also includes supporting concepts from other hierarchies, e.g. property values.

Planned areas of promotion for the July 2021 release include histologic type, histologic grade, invasion and lymph nodes. Additional promotion of content is planned for subsequent International releases. 

For more information about this project, please see the Cancer Synoptic Reporting Clinical Project Group here

Nutrition Content

• Addition of ~165 nutrition observable entity concepts.
• Review and remodeling of ~140 diet (regime/therapy) concepts
• Further information about the work of the Nutrition Care Process Clinical Project group is available here.

Updates for Teletherapy and Teleradiotherapy Concepts

• ~60 concepts which include "teletherapy" or "teleradiotherapy" in the FSN will be updated to include "external beam radiation therapy." Descriptions with "teletherapy" and "teleradiotherapy" will be retained.
• ~7 concepts which include "external beam" in the FSN will be modified to include "external beam radiation therapy" in the FSN.
• 49569001 |Consultation in teletherapy (procedure)| will be inactivated and replaced with a new concept: "Consultation in external beam radiation therapy (procedure).

Update to 271422003 |Fit denture (procedure)|subhierarchy

• Following discussions with the Dentistry CRG the concepts in this subhierarchy will be remodeled with the finding site of 28035005 |Structure of teeth, gums, and supporting structures (body structure)|or a subtype.
• Ambiguous concepts will be inactivated and replaced e.g. 6502003 |Complete lower denture (procedure)| will be replaced by 1144276002 |Fitting of complete lower denture (procedure)|.
• This will require changes to ~25 concepts, which will include ~15 inactivations.

Supernumerary tooth content

Approximately 69 disorder concepts <<367534004 Supernumerary tooth (disorder) will be remodeled to subsume under 371136004 Disorder of tooth development (disorder) and will have the value of their 116676008 |Associated morphology (attribute) relationship changed to 91431006 |Supernumerary structure (morphologic abnormality)|.

Inactivation of 266414008 |Supernumerary tooth (morphologic abnormality) sub-hierarchy (this will be inactivation of approximately 60 concepts).

Updates for concepts with "pacemaker"

Concepts which refer to a cardiac pacemaker but do not include "cardiac" in the FSN will be updated to include "cardiac pacemaker." If content is ambiguous as to the location of the pacemaker, then it will be inactivated and replaced.

41969006 |Idiopathic disease (disorder)

The almost 350 disorder concepts that specify ‘idiopathic’ in the FSN will be remodeled to have 41969006 |Idiopathic disease (disorder)| as a supertype. 

Inactivation of subtypes of 267280004 |Venous complication of pregnancy and/or puerperium (disorder)|

Classification-derived descendants of 267280004 |Venous complication of pregnancy and/or puerperium (disorder)| are being inactivated.

For example, |Superficial thrombophlebitis in pregnancy and the puerperium - delivered with postnatal complication (disorder)|

Inactivation of 3 ambiguous concepts in the body structure hierarchy: 

303295006 |Choroidal and/or retinal structures (body structure)| 

721949003 |Structure of choroid and/or retina of left eye (body structure)| 

721948006 |Structure of choroid and/or retina of right eye (body structure)|

• Disorder/procedure concepts which use these anatomic structures were remodeled with 2 role groups, one representing the finding site of 68703001 |Choroidal structure (body structure)| and the other for the 5665001 |Retinal structure (body structure)|.

• Majority of modeling changes were for ‘chorioretinal’ disorder concepts, findings and procedures.

• 3 procedures were remodeled plus one inactivation of 75278007 |Destruction of chorioretinopathy (procedure)|.

• Approximately 54 disorder concepts were remodeled, including 53854005 |Chorioretinal scar (disorder)| and its 18 subtypes. Two concept inactivations 69811008 |Peripheral disseminated choroiditis AND chorioretinitis (disorder)| and 56787009 |Peripheral focal choroiditis AND chorioretinitis (disorder)|.

• New anatomy concepts created 1137449006 |Structure of posterior pole of left eye (body structure)| and 1137450006 |Structure of posterior pole of right eye (body structure)|.

• Approximately 30 clinical finding concepts were remodeled including 9 subretinal findings and 7 subretinal disorders all remodeled with a finding site of 41275009|Structure of retinal pigment epithelium (body structure)|.

Inactivation of 19410003 |Macrocephaly (disorder)| and 1829003|Microcephalus (disorder)|

19410003 |Macrocephaly (disorder)| has been inactivated and replaced by two concepts:

• 1145402008 |Congenital macrocephaly (disorder)|
• 1145403003 |Macrocephaly (finding)|

1829003|Microcephalus (disorder)| has been inactivated and replaced by two new concepts

• 1148758003 |Congenital microcephaly (disorder)|
• 1148757008 |Microcephaly (finding)|

Inactivation of 34248003 |Rheumatic inflammation (morphologic abnormality)| and 103628006 |Chronic rheumatic inflammation (morphologic abnormality)|

Inactivation of 34248003 |Rheumatic inflammation (morphologic abnormality)| and 103628006 |Chronic rheumatic inflammation (morphologic abnormality)|.

Remodeled: 23685000 |Rheumatic heart disease (disorder)| and subtypes, and 195528001 |Acute rheumatic fever (disorder)| and subtypes. 

A model was developed for rheumatoid arthritis extra-articular manifestations (with expert input), and relevant concepts remodelled utilising parent concept 52661003 |Extra-articular rheumatoid process (disorder)| .

Disorder X without Disorder Y

The vast majority of existing X without Y concepts originated from ICD-9 with the specific meaning of "X disorder without mention of Y disorder".  As the phraseology indicates a lack of data about disorder Y as opposed to a specific exclusion, this type of concept has not been included in ICD-10, nor proposed for ICD-11, except in the case of "Traumatic brain injury without open intracranial wound".  

Addition of new X without Y concepts may only be made under the following conditions:

1. The request for new content must be accompanied by a rationale as to the difference between "X disorder without Y disorder" and "X disorder."
2. Approval for addition is given by the Head of Terminology.

For the most part, existing X without Y concepts will be inactivated as AMBIGUOUS with a historical MAY BE relationship to "X disorder".  Exceptions to inactivation will be made on a case-by-case basis.

Update Descriptions for Subtypes of 418272005|Computed tomography angiography with contrast (procedure)|

Update to the descriptions for CT arteriography and CT venography concepts in the procedure hierarchy to align with the editorial guide for Computed Tomography - CT.

Inactivation of subtypes of 77477000|Computerized axial tomography (procedure)|

303678006 |Computed tomography of regions (procedure)| has been inactivated with reason ambiguous and Possibly equivalent to 77477000 |Computerized axial tomography (procedure)|

303679003 |Computed tomography of systems (procedure)| has been inactivated with reason ambiguous Possibly equivalent to 77477000 |Computerized axial tomography (procedure)|

Content Improvements in the Substance and Product Hierarchies

Please see briefing notes here Drugs Project 

For the July 2021 International edition of SNOMED CT, the following changes will be made:

• Add new attribute 1149367008 |Has target population (attribute)| and transition existing instances of 860781008 |Has product characteristic (attribute)| to the new attribute.

• Add new attribute 1149366004 |Has ingredient qualitative strength (attribute)| and transition existing instances of 860779006 |Has ingredient characteristic (attribute)| to the new attribute.

• The existing attributes 860781008 |Has product characteristic (attribute)| and 860779006 |Has ingredient characteristic (attribute)| will no longer be used for modeling in the International Release.

• With the introduction of the new explicit attributes, the existing concepts 860781008 |Has product characteristic (attribute)| and 860779006 |Has ingredient characteristic (attribute)| no longer conform to SNOMED CT editorial guidance as the meaning of the attributes will change with the introduction of more explicit attributes.

  • 860781008 |Has product characteristic (attribute)| and 860779006 |Has ingredient characteristic (attribute)| will be inactivated at a yet to be determined future date.

  • Users and implementers are encouraged not to use these attributes and to request addition of specific attributes to support modeling in national extensions moving forward.

The following editorial guides are now available via the SNOMED CT Document Library:

• SNOMED CT Editorial Guide - Pharmaceutical Dose Form
• SNOMED CT Editorial Guide - Pharmaceutical and Biologic Product (includes the Medicinal Product hierarchy)

See: https://confluence.ihtsdotools.org/display/DOCEG

Please contact info@snomed.org with any inquiries.

Content Improvements in the Physical Object Hierarchy

Please see project roadmap and briefing notes here: https://confluence.ihtsdotools.org/display/IAP/Devices+Project

Content inactivations are planned for July 2021 International release:

• Inactivation of ~1200 physical object concepts that include use frequency (e.g., "single use catheter")
• Inactivation of ~600 physical object concepts that include a size or dimension (e.g., "30 cm catheter")

Physical object concepts that are described as a kit or set have been inactivated with reason 'nonconformance to editorial policy' without a replacement concept. Exceptions are noted in the editorial guidelines for the Physical object hierarchy.

New attribute types for Has absorbability quality, Has surface quality, Is sterile, and Has coating material will be added for 2021-July. Existing attribute types for Has surface characteristic and Has device characteristic will be inactivated. Further details are available in the briefing note posted on the Device Project space (Devices Project) and will be added to the organizing principles in the near future.

Please contact info@snomed.org with any inquiries.

WAS_A

Inactivation reason of LIMITED/WAS_A is not allowed for any new content inactivations after the July 2018 release. The WAS_A association refset has not been updated thereafter.

At the Editorial Advisory Group meeting in April 2019, agreement was reached to discontinue the maintenance of WAS_A relationships when inactivating concepts that have a historical association to an inactive concept. When changes are made to a historical relationship for a concept that was previously inactivated using WAS_A, effort will be made to assign a new historical relationship that facilitates traceability of the concept (e.g. DUPLICATE or AMBIGUOUS) as opposed to NON-CONFORMANCE TO EDITORIAL POLICY.

Existing WAS_A relationships will be inactivated in a future release once a plan for batch reassignment of historical relationships has been developed. Until then, SNOMED International will not continue to use or maintain WAS_A relationships.

Planned changes for 'Has ingredient characteristic’ and 'Has product characteristic’ and 'Has device characteristic' attributes

Based on guidance provided by the Editorial Advisory Group, the 'Has ingredient characteristic', 'Has product characteristic' and 'Has device characteristic' attributes will be refined to more specific attributes in a future release.

Concrete Domains and Numeric Representation

The Modeling Advisory Group is working on concrete domains and how they will be represented in the inferred RF2 relationship file format. The following is a note on the interim solution relating to concrete domain for the medicinal product model:

Numerics are represented by concepts in the Medicinal product concept model in SNOMED CT, which is an interim solution before the implementation of concrete domains to support data types, such as decimal, integer, string and date/time. We are in progress for the development of the specification for the inferred relationship file and consult with the community of practice. When they are ready, strength in medicinal product model can be transformed to concrete domains. The transformation will be completed by technical changes without impact to classification results.

The further information about current progress on Concrete Domains can be found at:

https://confluence.ihtsdotools.org/display/mag/Modeling+Advisory+Group 

February 2021 SNOMED CT International Edition Concrete Domains Technical Preview release available

NOTE:

For the January 2022 International release, descriptions have been updated for all concepts containing “Severe acute respiratory syndrome coronavirus 2” to remove capitalization from ''Severe” (except when it is found at the beginning of the description in accordance with editorial guidance).

In addition, “Severe acute respiratory syndrome coronavirus 2”  is recorded as entire term case insensitive. Our authoritative resource, International Committee on Taxonomy of Viruses (ICTV), does not have an entry for viruses below species level and the majority of references, including scientific literature, do not capitalize ”severe''.

January 2022 International Release and future releases

Browse Content Changes for the January 2022 Release

The daily build is available to review changes made to content for the January 2022 release https://dailybuild.ihtsdotools.org/

Forthcoming concept inactivations, new concepts and changes to existing concepts can be reviewed using the tab 'Daily build.'

Implementation of the new anatomy concept model

The completion of the revision of hierarchical relationships provides stable anatomy content and improves the quality of classification results in other hierarchies.

Over forthcoming releases, the plan is to implement the new anatomy concept model. There are almost 35,000 anatomy concepts and they will be modeled by different types of 'part of' relationships. The new model will enable us to automatically generate hierarchies to further improve quality and consistency. 

Information about the work completed in previous release for revision of IS_A relationships can be viewed here: https://confluence.ihtsdotools.org/display/IAP/Revision+of+IS-A+relationships+for+anatomy

January 2022 International Release and future releases

MRCM Changes

Please see MRCM changes in the January 2022 release

Quality Initiative

Information about the project can found here - Quality Initiative - Progress

Note: There are changes to the Service Level Agreement for the CRS as a result of the Quality Initiative:

https://www.snomed.org/SNOMED/media/SNOMED/documents/Changes-to-SLA_202005_MHA.pdf

Change for Clinical Drug Concepts Containing Pancreatic Enzymes

Clinical drug concepts in the International Release containing pancreatic enzymes will be modeled based on the discrete enzymes; because of variability between real clinical drugs, synonyms representing a total amount in a particular product will not be included in the International Release.

The editorial guide and existing content will be reviewed and updated accordingly in a future release.

Changes for Pressure Injury

A new hierarchy, 1163215007 |Pressure injury (disorder)|has been created in SNOMED CT based on the recommendations of the National Pressure Injury Advisory Panel (NPIAP) and adopted for the 2019 international clinical practice guidelines on the prevention and treatment of pressure ulcers/injuries. The NPIAP nomenclature favors the use of pressure injury over pressure ulcer due to confusion around the use of ulcer for two of the pressure ulcer stages which actually occur in intact skin.

Changes for 150062003 |Osteotomy (procedure) subtypes

The concepts under 150062003 |Osteotomy (procedure)| have been remodeled to reflect that an Osteotomy is an incision, excision or division of bone.  There had been a pair of methods 299713009 |Osteotomy - action (qualifier value)| and 439315000 |Wedge osteotomy - action (qualifier value)| under 129287005 |Incision - action (qualifier value)| that did not represent the breadth of meaning of osteotomy. 

All osteotomy concepts have been remodeled using the appropriate METHOD relationship value and according to the proximal primitive parent modeling construct according to a defined template.  

299713009 |Osteotomy - action (qualifier value)| and 439315000 |Wedge osteotomy - action (qualifier value)| have been inactivated.

Due to the equivalence between Osteotomy and Incision of bone, concepts with the FSN including "Incision of bone" have been inactivated as duplicate to "Osteotomy of bone" and the Incision descriptions added to the Osteotomy concepts.

Inactivation of 362977000 |Sequela (disorder)| and remodeling of subtypes

As discussed and approved by the SNOMED Editorial Advisory Group on 10/07/2020, the grouper concept 362977000 |Sequela (disorder)| will be inactivated and the subtypes remodeled in the general pattern of;

64572001 |Disease (disorder)| AFTER (64572001 |Disease (disorder)| or 71388002 |Procedure (procedure)|)

Concepts with FSNs containing the terms “sequela, sequelae or “late effects” will not have their FSNs changed. Aside from changes due to the remodeling pattern, the current inferred IS A relationships will be retained.  The primary change will be elimination of their placement in a separate Sequela hierarchy.  Additional sequela grouper concepts (e.g. 363296001 |Sequelae of disorders classified by disorder-system (disorder)|) will be initially remodeled, but are being evaluated for inactivation. 

Planned Inactivation of Concepts in the 260299005 |Number (qualifier value)| Hierarchy

Following the deployment of the concrete domain functionality in SNOMED CT, concepts in the 260299005 |Number (qualifier value)| hierarchy are no longer necessary and plans have been made for their inactivation.

To provide adequate time for any national extension or implementation affected by this change, concepts in the 260299005 |Number (qualifier value)| hierarchy will be inactivated in the January 2023 International Release.

Concepts will be inactivated with reason “Non-conformance to editorial policy” and no historical relationship or replacement concept will be provided.

Exceptions:

118586006 |Ratio (property) (qualifier value)| and descendants have been relocated to 118598001 |Property (qualifier value)| hierarchy.

272070003 |Ordinal number (qualifier value)| and descendants have been relocated to 362981000 |Qualifier value (qualifier value)| hierarchy.

A briefing note will also be distributed to selected Advisory and Project Groups.

Please contact info@snomed.org with any inquiries.

Concepts referencing substance structural groupers of form "X and X derivative" or "Y and Y compound"

Around 500 concepts in multiple hierarchies with FSNs that include either "X and X derivative" or "Y and Y compound" will have terming updated to "X and/or X derivative" and "Y and/or Y compound," respectively.

Please see the briefing note for more information.

Review and Update modeling for 87568004 |Hormone (substance)| and Descendants

Changes will include inactivation of ambiguous groupers such as 419570005 |Hormone, synthetic hormone substitute or hormone antagonist (substance)| and 278421003 |Hormones and their metabolites and precursors (substance)| and 304360003 |Peptide hormones and their metabolites and precursors (substance)|.

Remodel 420721002 |Acquired immunodeficiency syndrome-associated disorder (disorder) and descendants

420721002 |Acquired immunodeficiency syndrome-associated disorder (disorder)| has been made primitive and its 73 subtypes have been remodeled. 

The |Associated with (attribute)| is eliminated and descriptions updated accordingly.  Role groups were added to support concept definition. The AIDS acronym has been annotated in expanded form as per Editorial Guidance. 

Review of tooth/teeth content

Changes are expected to approximately 120 concepts. Any concept which contains a mix of plural and singular descriptions will be changed so that the concept only represents a singular “tooth” or plural “teeth”. Where appropriate, new concepts will be created. An example concept to be changed is 36202009 |Fracture of tooth (disorder)| which has an incorrect plural description of “Broken teeth”.

Modeling will be reviewed to ensure that a plural FSN (teeth) has a plural finding site and a singular FSN (tooth) has a singular finding site. Changes to the modeling of concepts will be made where necessary. An example concept to be changed is 53963006 |Excessive attrition of teeth (disorder)|which is currently modeled with a singular finding site.

Review of 2556008 |Periodontal disease (disorder)| and descendants

This review is part of content tracker IHTSDO-720 and will include ~130 concepts. Changes will be made following input from the Dentistry CRG and will include:

• The inactivation of ~20 concepts due to being outdated or duplicate content. An example concept that will be inactivated as outdated is 49965002 |Juvenile periodontitis (disorder)| which will have an inactivation target of 449908004 |Aggressive periodontitis (disorder)|. 
• ~15 concepts will have their fully specified name reviewed by the Dentistry CRG. Changes will be made to ensure descriptions follow agreed naming patterns and that relationships between conditions are accurately represented. An example concept for review is 709466003 |Periodontitis co-occurrent with Cohen syndrome (disorder)|.
• The addition of subtypes under 699785004 |Periodontitis as manifestation of systemic disease (disorder)|in line with the American Academy of Periodontology and European Federation of Periodontology 2017 Classification of Periodontal and Peri‐implant Diseases and Conditions.
• The review of all concept definitions and descriptions. These will be remodeled and updated, where appropriate.

Compression Hosiery

Concepts referring to compression hosiery of a specific class (e.g. class I) have been updated to include a text definition that indicates the concept "serves as the parent of concepts representing an actual manufactured item whose description includes the explicit compression range associated with the class rating for that item.”

Inactivation of 410795001 |Juvenile rheumatoid arthritis (disorder)| and Remodeling of Descendants of 410502007 |Juvenile idiopathic arthritis (disorder)

410795001 |Juvenile rheumatoid arthritis (disorder)| has been inactivated with reason outdated and a replacement target of 410502007 |Juvenile idiopathic arthritis (disorder)|.
The subtypes of 410502007 |Juvenile idiopathic arthritis (disorder)| have been substantially remodeled with expert input and definitions added where appropriate. 

Revision Procedure X declined (situation)

131 Situation hierarchy concepts of the pattern "Procedure X declined (situation)" have been remodelled with DECLINED as both the FSN and the Preferred Term. 

Nutrition Content

• Addition of ~200 nutrition concepts. Most will be in the observable entity hierarchy (nutrition behaviors, social determinants, ability concepts), some in clinical findings (potable water access, nutrition activities of daily living findings) and a portion are regime/therapy concepts (infant feeding management). 
• Further information about the work of the Nutrition Care Process Clinical Project group is available here.

Revision of Overlapping Malignant Neoplasm Concepts Containing 'overlapping lesion'
The majority of these descriptions are of the pattern e.g.188157005 |Malignant neoplasm, overlapping lesion of breast (disorder)| and originate from ICD-9 and ICD-10.
Remodel for 78 overlapping malignant neoplasm concepts: 

• Updating of fully specified name and preferred term for concepts in the 363346000 |Malignant neoplastic disease (disorder)| subhierarchy where the FSN and PT descriptions contain 'overlapping lesion.' The FSN and PT have been changed to 'overlapping sites' without inactivation of the concepts or altering the meaning or model. Example: Malignant neoplasm, overlapping lesion of breast (disorder) has been updated to Malignant neoplasm of overlapping sites of breast (disorder).
• Addition of a new synonym containing 'overlapping sites' where the 'overlapping lesion' wording is an existing synonym.
• Where an existing overlapping malignant neoplasm concept was available this has been used as a proximal primitive parent to Sufficiently Define the concept.

Inactivation and replacement of neoplastic morphology concepts containing ICD-O-3 classification terming

Some ICD-O version 3 morphology classification codes include Not Otherwise Specified (NOS), these concepts are not acceptable in SNOMED CT as per Editorial Guidance and are not meaningful outside of the ICD-O classification context.

In the current 400177003 |Neoplasm and/or hamartoma (morphologic abnormality)| sub-hierarchy there are approximately 75 neoplastic morphology concepts containing  the terming "no International Classification of Diseases for Oncology subtype (morphologic abnormality)" and/or "no ICD-O subtype" originating from ICD-O-3 and they are utilized in the modeling of about 460 disorders in the 55342001 |Neoplastic disease (disorder)| hierarchy.

• The concepts "no International Classification of Diseases for Oncology subtype (morphologic abnormality)" and/or "no ICD-O subtype" will be inactivated with reason Outdated (pending the development of a specific inactivation reason for classification schema entities) and replaced with either a new concept or an existing suitable target concept. This work will be carried out in liaison with the Cancer Synoptic Reporting Clinical Project Group.
  • For example:18365006 |Adrenal cortical adenoma, no International Classification of Diseases for Oncology subtype (morphologic abnormality)| has been inactivated and replaced with 1156661006 |Adrenal cortical adenoma (morphologic abnormality)|. 
• Review and remodel of the neoplasm disorder concepts that utilize these morphologies. 
• Identify those neoplastic morphologic abnormalities in SNOMED CT which have non-synonymous descriptions originating from ICD-O-3. Inactivate these descriptions as non-semantically equivalent and recreate them as new subtype or sibling concept including remodel of relevant disorder concepts. 

Cancer Synoptic Reporting

Concepts representing cancer synoptic reporting content will be added to the International release starting with the July 2021 release. 

Cancer synoptic reports are used by many member countries to record pathology examination of cancer specimens including the College of American Pathologists (US and Canada), Royal College of Pathology (UK), Royal College of Pathology Australasia (Australia, New Zealand), PALGA (The Netherlands), Swedish Society of Pathology, and others.

This content primarily encompasses observable entity concepts and also includes supporting concepts from other hierarchies, e.g. property values.

Planned areas of promotion for the January 2022 release include margins, focality, depth, locations, immunohistochemistry and hematopoietic tumors. Additional promotion of content is planned for subsequent International releases.

For more information about this project, please see the Cancer Synoptic Reporting Clinical Project Group here

Disorder X without Disorder Y

The vast majority of existing X without Y concepts originated from ICD-9 with the specific meaning of "X disorder without mention of Y disorder".  As the phraseology indicates a lack of data about disorder Y as opposed to a specific exclusion, this type of concept has not been included in ICD-10, nor proposed for ICD-11, except in the case of "Traumatic brain injury without open intracranial wound".  

Addition of new X without Y concepts may only be made under the following conditions:

1. The request for new content must be accompanied by a rationale as to the difference between "X disorder without Y disorder" and "X disorder."
2. Approval for addition is given by the Head of Terminology.

For the most part, existing X without Y concepts will be inactivated as AMBIGUOUS with a historical MAY BE relationship to "X disorder".  Exceptions to inactivation will be made on a case-by-case basis.

Content Improvements in the Substance and Product Hierarchies

Please see briefing notes here Drugs Project 

Changes for Lyophilized Powder

Editorial guidelines have been updated to reflect that Clinical drug concepts in the International Release should not be modeled using dose forms for “lyophilized powder” because it is not a clinically relevant distinction at the Clinical drug level.

• Existing Clinical drug concepts will be inactivated and replaced with corresponding “powder” Pharmaceutical dose form for 2022-January Release.
• Existing Pharmaceutical dose forms referring to “lyophilized powder” will be retained in the International Release but will not be used for modeling; they can be used for modeling in national extensions.

Editorial Guidelines for Semi-Solid Dose Form

Editorial guidelines have been updated to reflect that Clinical drug concepts in the International Release with semi-solid dose form should have strength denominator normalized to:

• /1 gram for weight/weight concentration
• /1 milliliter for weight/volume concentration

Existing Clinical drug concepts will be updated for 2022-January Release.

Content Improvements in the Physical Object Hierarchy

Please see project roadmap and briefing notes here: https://confluence.ihtsdotools.org/display/IAP/Devices+Project

WAS_A

Inactivation reason of LIMITED/WAS_A is not allowed for any new content inactivations after the July 2018 release. The WAS_A association refset has not been updated thereafter.

At the Editorial Advisory Group meeting in April 2019, agreement was reached to discontinue the maintenance of WAS_A relationships when inactivating concepts that have a historical association to an inactive concept. When changes are made to a historical relationship for a concept that was previously inactivated using WAS_A, effort will be made to assign a new historical relationship that facilitates traceability of the concept (e.g. DUPLICATE or AMBIGUOUS) as opposed to NON-CONFORMANCE TO EDITORIAL POLICY.

Existing WAS_A relationships will be inactivated in a future release once a plan for batch reassignment of historical relationships has been developed. Until then, SNOMED International will not continue to use or maintain WAS_A relationships.