LOINC Code 21855-2: Primary site Cancer
21855-2 is a LOINC code used to identify Primary site 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 Primary site. 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 Primary site. 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
- Primary site Cancer
- Primary site
- Code for the primary site of the tumor being reported using either ICD-O-2 or ICD-O-3. NAACCR adopted ICD-O-2 as the standard coding system for tumors diagnosed beginning January 1, 1992. In addition, NAACCR recommended that tumors diagnosed prior to 1992 be converted to ICD-O-2. The topography (primary site) codes have not changed between ICD-O-2 and ICD-O-3... NAACCR Data Standards and Data Dictionary Version 11
- Anatomy; CA; Misc; Miscellaneous; Nominal; Oncology; Other; Point in time; Random; Spec; To be specified in another part of the message; TUMOR REGISTRY(NAACCR); 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.