# Cancer.gov Metadata endpoints API

**Canonical:** https://apis.io/apis/cancer-gov/cancer-gov-metadata-endpoints-api/  
**Provider:** Cancer.gov — https://apis.io/providers/cancer-gov/  
**Base URL:** https://clinicaltrialsapi.cancer.gov/api/v2  
**Documentation:** https://clinicaltrialsapi.cancer.gov/

Cancer.gov Metadata endpoints API is one of 48 APIs that [Cancer.gov](https://apis.io/providers/cancer-gov/) publishes on the [APIs.io](https://apis.io/) network, described by a machine-readable OpenAPI specification. Tagged areas include Metadata endpoints. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, rate-limit docs, and an API reference.

The Metadata endpoints API from Cancer.gov — 24 operation(s) for metadata endpoints.

## Operations (24)

| Method | Path | Summary |
|---|---|---|
| GET | `/api/v1/metadata/{terminology}` | Get some metadata (associations, properties, qualifiers, roles, term types… |
| GET | `/api/v1/metadata/{terminology}/welcomeText` | Get welcome text for the specified terminology |
| GET | `/api/v1/metadata/{terminology}/termTypes` | Get all term types for the specified terminology |
| GET | `/api/v1/metadata/{terminology}/synonymTypes` | Get all synonym types (or those specified by list parameter) for the specified… |
| GET | `/api/v1/metadata/{terminology}/synonymType/{codeOrName}` | Get the synonym type for the specified terminology and code/name |
| GET | `/api/v1/metadata/{terminology}/synonymSources` | Get all synonym sources for the specified terminology |
| GET | `/api/v1/metadata/{terminology}/subsets` | Get all subsets (or those specified by list parameter) for the specified… |
| GET | `/api/v1/metadata/{terminology}/subset/{code}` | Get the subset for the specified terminology and code |
| GET | `/api/v1/metadata/{terminology}/stats/{source}` | Get statistics for the source within the specified terminology |
| GET | `/api/v1/metadata/{terminology}/roles` | Get all roles (or those specified by list parameter) for the specified… |
| GET | `/api/v1/metadata/{terminology}/role/{codeOrName}` | Get the role for the specified terminology and code/name |
| GET | `/api/v1/metadata/{terminology}/qualifiers` | Get all qualifiers (properties on properties) for the specified terminology |
| GET | `/api/v1/metadata/{terminology}/qualifier/{codeOrName}` | Get the qualifier for the specified terminology and code/name |
| GET | `/api/v1/metadata/{terminology}/qualifier/{codeOrName}/values` | Get qualifier values for the specified terminology and code/name |
| GET | `/api/v1/metadata/{terminology}/property/{codeOrName}` | Get the property for the specified terminology and code/name |
| GET | `/api/v1/metadata/{terminology}/property/{codeOrName}/values` | Get property values for the specified terminology and code/name |
| GET | `/api/v1/metadata/{terminology}/properties` | Get all properties (or those specified by list parameter) for the specified… |
| GET | `/api/v1/metadata/{terminology}/definitionTypes` | Get all definition types (or those specified by list parameter) for the… |
| GET | `/api/v1/metadata/{terminology}/definitionType/{codeOrName}` | Get the definition type for the specified terminology and code/name |
| GET | `/api/v1/metadata/{terminology}/definitionSources` | Get all definition sources for the specified terminology |
| GET | `/api/v1/metadata/{terminology}/conceptStatuses` | Get all concept status values for the specified terminology |
| GET | `/api/v1/metadata/{terminology}/associations` | Get all associations (or those specified by list parameter) for the specified… |
| GET | `/api/v1/metadata/{terminology}/association/{codeOrName}` | Get the association for the specified terminology and code/name |
| GET | `/api/v1/metadata/terminologies` | Get all available terminologies |

## Machine-readable artifacts (21)

- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/cancer-gov/refs/heads/main/openapi/cancer-gov-metadata-endpoints-api-openapi.yml
- **Documentation** — https://api.seer.cancer.gov/docs
- **Portal** — https://api.seer.cancer.gov/
- **TermsOfService** — https://api.seer.cancer.gov/terms
- **RateLimits** — https://raw.githubusercontent.com/api-evangelist/cancer-gov/refs/heads/main/rate-limits/cancer-gov-rate-limits.yml
- **APIReference** — https://api.seer.cancer.gov/docs
- **Documentation** — https://modac.cancer.gov/swagger-ui/4.14.0/index.html
- **Portal** — https://modac.cancer.gov/
- **Documentation** — https://evs.nci.nih.gov/
- **Explorer** — https://evsexplore.semantics.cancer.gov/
- **WhitePaper** — https://evs.nci.nih.gov/ftp1/NCI_Metathesaurus/EVS%20Metathesaurus%20White%20Paper.pdf
- **APIReference** — https://api-evsrest.nci.nih.gov/swagger-ui/index.html
- **SourceCode** — https://github.com/NCIEVS/evsrestapi
- **TermsOfService** — https://evs.nci.nih.gov/ftp1/NCI_Thesaurus/ThesaurusTermsofUse.htm
- **SourceCode** — https://github.com/NCIOCPL/glossary-api
- **Documentation** — https://webapis.cancer.gov/glossary/v1/
- **SourceCode** — https://github.com/NCIOCPL/drug-dictionary-api
- **Documentation** — https://webapis.cancer.gov/drugdictionary/v1/
- **SourceCode** — https://github.com/NCIOCPL/sitewide-search-api
- **SourceCode** — https://github.com/NCIOCPL/bestbets-api
- **SourceCode** — https://github.com/NCIOCPL/r4r-api

## Other Cancer.gov APIs (12)

- [NCI Clinical Trials Search API](https://apis.io/apis/cancer-gov/clinical-trials-api/)
- [NCI Genomic Data Commons (GDC) API](https://apis.io/apis/cancer-gov/gdc-api/)
- [NCI Content Syndication Services](https://apis.io/apis/cancer-gov/syndication-services/)
- [Cancer.gov Diseases API](https://apis.io/apis/cancer-gov/cancer-gov-diseases-api/)
- [Cancer.gov Interventions API](https://apis.io/apis/cancer-gov/cancer-gov-interventions-api/)
- [Cancer.gov Terms API](https://apis.io/apis/cancer-gov/cancer-gov-terms-api/)
- [Cancer.gov Trials API](https://apis.io/apis/cancer-gov/cancer-gov-trials-api/)
- [Cancer.gov Application version endpoint API](https://apis.io/apis/cancer-gov/cancer-gov-application-version-endpoint-api/)
- [Cancer.gov Asset Details Controller API](https://apis.io/apis/cancer-gov/cancer-gov-asset-details-controller-api/)
- [Cancer.gov Autosuggest API](https://apis.io/apis/cancer-gov/cancer-gov-autosuggest-api/)
- [Cancer.gov Concept endpoints API](https://apis.io/apis/cancer-gov/cancer-gov-concept-endpoints-api/)
- [Cancer.gov Delete Collection Controller API](https://apis.io/apis/cancer-gov/cancer-gov-delete-collection-controller-api/)

## Tags

Metadata endpoints

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/cancer-gov/cancer-gov-metadata-endpoints-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/cancer-gov/.