What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINCActiveBoth

LOINC Code 50776-4: Cancer Ag 15-3 Qn (CSF)

Name: LOINC Code 50776-4: Cancer Ag 15-3 Qn (CSF)
Creator: HealthAssure Clinical Team
Published: 2026-05-25T17:13:11.347Z

50776-4 is a LOINC code used to identify Cancer Ag 15-3 Qn (CSF) 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 Cancer Ag 15-3. It is commonly used with the system or sample type CSF.

Reviewed by HealthAssure Clinical TeamUpdated 25 May 2026

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 Cancer Ag 15-3. It is commonly used with the system or sample type CSF.

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
Order vs observation: Both

What it does not mean

The code identifies the observation or test, not the actual result.

Key facts

Cancer Ag 15-3 [Units/volume] in Cerebral spinal fluid
Cancer Ag 15-3
Arbitrary concentration; CA; CA 153; CA 15-3; Cancer Ag15-3; Carbohydrate antigen; Cerebral spinal fluid; Cerebrospinal Fl; Chemistry; III; MUC-1 gene associated AG CA 15-3; Neuro; Neurology; Oncology; Point in time; QNT; Quan; Quant; Quantitative; Random; Spinal Fl; Spinal Fld; Spinal Flu; Spinal Fluid; Tumor marker

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.

Related SNOMED CT concepts

705114005SNOMED CT mapping for Cancer Ag 15-3 Qn (CSF) (50776-4)

Related observations and tests

SNOMED_CT 705114005high

LOINC Code System

Source: LOINC-SNOMED cooperation package

Common synonyms

Cancer Ag 15-3 Qn (CSF)Cancer Ag 15-3 [Units/volume] in Cerebral spinal fluidCancer Ag15-3 CSF-aCncCancer Ag 15-3CHEMCancer Ag 15-3, Spinal fluidACnc

Frequently asked questions

Code details

Code50776-4

SystemLOINC

Display nameCancer Ag 15-3 Qn (CSF)

DescriptionCancer Ag 15-3

Short nameCancer Ag15-3 CSF-aCnc

ComponentCancer Ag 15-3

PropertyACnc

TimingPt

System (specimen)CSF

ScaleQn

ClassCHEM

Example unitsarb U/L

StatusACTIVE

Order/ObservationBoth

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.22

Last changed2.68

Consumer names

Cancer Ag 15-3, Spinal fluid

Part names

Cancer Ag 15-3ACncPtCSFQnArbitrary ConcentrationPoint in time (spot)Cerebral spinal fluid

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.