LOINC Code 21890-9: Extension Cancer
21890-9 is a LOINC code used to identify Extension Cancer in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Extension. It is commonly used with the system or sample type Cancer.XXX.
What is this code?
LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Extension. It is commonly used with the system or sample type Cancer.XXX.
When is it used?
- Used in lab systems, EHRs, and clinical data exchange.
- May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
- Status: ACTIVE
What it does not mean
- The code identifies the observation or test, not the actual result.
Key facts
- Extension Cancer
- Extension
- Part of the 10-digit EOD [779]. Detailed site-specific codes for anatomic EOD used by SEER for tumors diagnosed from 1988 forward. This field is included in the COC dataset, separate from EOD. Codes were revised effective January 1, 1998, to reflect changes in the AJCC Cancer Staging Manual, Fifth Edition. Site-specific EOD codes provide extensive detail describing disease extent. The EOD codes can be grouped into different stage categories for analysis (e.g., historical summary stage categories consistent with those used in published SEER data since 1973, or more recently, AJCC stage groupings). The codes are updated as needed, but updates are usually backward compatible with old categories. See Comparative Staging Guide for Cancer.. NAACCR Data Standards and Data Dictionary Version 11
- CA; EXT; Misc; Miscellaneous; Nominal; Oncology; Other; Point in time; Random; Spec; To be specified in another part of the message; TUMOR REGISTRY(NAACCR); Typ; Unspecified
Where you may see this code
You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.
Common synonyms
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.