CA 19-9
CA 19-9 is a tumor marker protein that can be elevated in pancreatic and other digestive tract cancers.
CA 19-9
Normal range
Normal range
<37 kU/L
<37 kU/L
Normal range
<37 kU/L
<37 kU/L
Normal range
CA 19-9
CA 19-9
CA 19-9 is a tumor marker protein that can be elevated in pancreatic and other digestive tract cancers.
CA 19-9
Normal range
<37 kU/L
Normal range
<37 kU/L
<37 kU/L
Normal range
CA 19-9
CA 19-9
CA 19-9 is a tumor marker protein that can be elevated in pancreatic and other digestive tract cancers.
CA 19-9
Normal range
<37 kU/L
Normal range
<37 kU/L
<37 kU/L
Normal range
CA 19-9
CA 19-9
CA 19-9 is a tumor marker protein that can be elevated in pancreatic and other digestive tract cancers.
CA 19-9
Normal range
<37 kU/L
Normal range
<37 kU/L
<37 kU/L
Normal range
CA 19-9
Dr. Daniel McNally
MBBS
Your Body's Digestive Health Monitor
Your Body's Digestive Health Monitor
Your Body's Digestive Health Monitor
Cancer Antigen 19-9 (CA 19-9) is a protein produced by certain cells in your digestive system that serves as a specialised monitoring tool rather than a routine screening test. In healthy individuals, CA 19-9 levels remain very low, but when certain digestive conditions develop, these levels can rise, providing doctors with valuable information for monitoring and treatment guidance. Think of CA 19-9 as a biochemical messenger that helps track specific digestive health conditions.
CA 19-9 testing becomes particularly valuable for people who've been diagnosed with certain pancreatic and digestive cancers, where it helps doctors monitor treatment progress and detect changes over time. Unlike routine blood tests that screen for general health, CA 19-9 serves as a targeted monitoring tool used in specific clinical situations.
Cancer Antigen 19-9 (CA 19-9) is a protein produced by certain cells in your digestive system that serves as a specialised monitoring tool rather than a routine screening test. In healthy individuals, CA 19-9 levels remain very low, but when certain digestive conditions develop, these levels can rise, providing doctors with valuable information for monitoring and treatment guidance. Think of CA 19-9 as a biochemical messenger that helps track specific digestive health conditions.
CA 19-9 testing becomes particularly valuable for people who've been diagnosed with certain pancreatic and digestive cancers, where it helps doctors monitor treatment progress and detect changes over time. Unlike routine blood tests that screen for general health, CA 19-9 serves as a targeted monitoring tool used in specific clinical situations.
When CA 19-9 Testing Provides Valuable Information
When CA 19-9 Testing Provides Valuable Information
When CA 19-9 Testing Provides Valuable Information
When CA 19-9 Testing Provides Valuable Information
Discover when doctors use this digestive protein marker and why it's particularly helpful for monitoring specific health conditions.
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What Influences Your CA 19-9 Levels
What Influences Your CA 19-9 Levels
What Influences Your CA 19-9 Levels
What Influences Your CA 19-9 Levels
Understanding the various factors that can affect CA 19-9 production and why individual levels vary significantly between people.
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CA 19-9's Role in Health Monitoring
CA 19-9's Role in Health Monitoring
CA 19-9's Role in Health Monitoring
CA 19-9's Role in Health Monitoring
Learn how doctors use CA 19-9 measurements to track treatment progress and guide medical decisions in digestive health conditions.
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Understanding Your Results
Understanding Your Results
Understanding Your Results
Understanding Your Results
Decode your numbers and know what different CA 19-9 levels mean for your digestive health and ongoing care.
Read more
When CA 19-9 Testing Provides Valuable Information
Normal CA 19-9 levels indicate that cells in your digestive system are producing typical amounts of this protein, with most healthy individuals having levels below 37 units per millilitre. These low levels represent normal cellular activity in your digestive tract and provide reassurance.
CA 19-9 testing becomes most valuable for people who've been diagnosed with certain digestive conditions, particularly cancers involving the pancreas, stomach, or intestinal tract. CA 19-9 is most appropriately used in monitoring disease progression or effectiveness of treatment once diagnosis has been made and serum concentrations have been shown to be raised prior to treatment.
The test helps doctors track how well treatments are working and detect changes that might require adjustments to medical care. Rising CA 19-9 values may indicate progression, whilst decreasing values often suggest treatment effectiveness, providing objective measurements that complement clinical assessment.
It's important to understand that CA 19-9 testing has limitations—some people naturally don't produce this protein and elevated levels can occur in various non-cancerous conditions, which is why doctors use this test strategically rather than for general screening.
When CA 19-9 Testing Provides Valuable Information
Normal CA 19-9 levels indicate that cells in your digestive system are producing typical amounts of this protein, with most healthy individuals having levels below 37 units per millilitre. These low levels represent normal cellular activity in your digestive tract and provide reassurance.
CA 19-9 testing becomes most valuable for people who've been diagnosed with certain digestive conditions, particularly cancers involving the pancreas, stomach, or intestinal tract. CA 19-9 is most appropriately used in monitoring disease progression or effectiveness of treatment once diagnosis has been made and serum concentrations have been shown to be raised prior to treatment.
The test helps doctors track how well treatments are working and detect changes that might require adjustments to medical care. Rising CA 19-9 values may indicate progression, whilst decreasing values often suggest treatment effectiveness, providing objective measurements that complement clinical assessment.
It's important to understand that CA 19-9 testing has limitations—some people naturally don't produce this protein and elevated levels can occur in various non-cancerous conditions, which is why doctors use this test strategically rather than for general screening.
When CA 19-9 Testing Provides Valuable Information
Normal CA 19-9 levels indicate that cells in your digestive system are producing typical amounts of this protein, with most healthy individuals having levels below 37 units per millilitre. These low levels represent normal cellular activity in your digestive tract and provide reassurance.
CA 19-9 testing becomes most valuable for people who've been diagnosed with certain digestive conditions, particularly cancers involving the pancreas, stomach, or intestinal tract. CA 19-9 is most appropriately used in monitoring disease progression or effectiveness of treatment once diagnosis has been made and serum concentrations have been shown to be raised prior to treatment.
The test helps doctors track how well treatments are working and detect changes that might require adjustments to medical care. Rising CA 19-9 values may indicate progression, whilst decreasing values often suggest treatment effectiveness, providing objective measurements that complement clinical assessment.
It's important to understand that CA 19-9 testing has limitations—some people naturally don't produce this protein and elevated levels can occur in various non-cancerous conditions, which is why doctors use this test strategically rather than for general screening.
When CA 19-9 Testing Provides Valuable Information
Normal CA 19-9 levels indicate that cells in your digestive system are producing typical amounts of this protein, with most healthy individuals having levels below 37 units per millilitre. These low levels represent normal cellular activity in your digestive tract and provide reassurance.
CA 19-9 testing becomes most valuable for people who've been diagnosed with certain digestive conditions, particularly cancers involving the pancreas, stomach, or intestinal tract. CA 19-9 is most appropriately used in monitoring disease progression or effectiveness of treatment once diagnosis has been made and serum concentrations have been shown to be raised prior to treatment.
The test helps doctors track how well treatments are working and detect changes that might require adjustments to medical care. Rising CA 19-9 values may indicate progression, whilst decreasing values often suggest treatment effectiveness, providing objective measurements that complement clinical assessment.
It's important to understand that CA 19-9 testing has limitations—some people naturally don't produce this protein and elevated levels can occur in various non-cancerous conditions, which is why doctors use this test strategically rather than for general screening.
What Influences Your CA 19-9 Levels
Several digestive conditions can naturally elevate CA 19-9 levels beyond the normal range. CA 19-9 has been shown to be raised in pancreatic adenocarcinomas (most), gastric carcinomas (50%), and colorectal carcinomas (30%). Non-cancerous conditions can also affect CA 19-9 levels, including liver conditions, bile duct problems, and inflammatory digestive disorders.
Genetic variation plays a significant role in CA 19-9 production, with approximately 5-10% of the population being "Lewis negative," meaning they naturally produce little or no CA 19-9 regardless of their health status. This genetic variation explains why doctors consider individual baselines when interpreting results.
Age, gender, and other individual factors can influence CA 19-9 levels, though these variations are typically modest compared to changes caused by specific health conditions requiring medical attention.
What Influences Your CA 19-9 Levels
Several digestive conditions can naturally elevate CA 19-9 levels beyond the normal range. CA 19-9 has been shown to be raised in pancreatic adenocarcinomas (most), gastric carcinomas (50%), and colorectal carcinomas (30%). Non-cancerous conditions can also affect CA 19-9 levels, including liver conditions, bile duct problems, and inflammatory digestive disorders.
Genetic variation plays a significant role in CA 19-9 production, with approximately 5-10% of the population being "Lewis negative," meaning they naturally produce little or no CA 19-9 regardless of their health status. This genetic variation explains why doctors consider individual baselines when interpreting results.
Age, gender, and other individual factors can influence CA 19-9 levels, though these variations are typically modest compared to changes caused by specific health conditions requiring medical attention.
What Influences Your CA 19-9 Levels
Several digestive conditions can naturally elevate CA 19-9 levels beyond the normal range. CA 19-9 has been shown to be raised in pancreatic adenocarcinomas (most), gastric carcinomas (50%), and colorectal carcinomas (30%). Non-cancerous conditions can also affect CA 19-9 levels, including liver conditions, bile duct problems, and inflammatory digestive disorders.
Genetic variation plays a significant role in CA 19-9 production, with approximately 5-10% of the population being "Lewis negative," meaning they naturally produce little or no CA 19-9 regardless of their health status. This genetic variation explains why doctors consider individual baselines when interpreting results.
Age, gender, and other individual factors can influence CA 19-9 levels, though these variations are typically modest compared to changes caused by specific health conditions requiring medical attention.
What Influences Your CA 19-9 Levels
Several digestive conditions can naturally elevate CA 19-9 levels beyond the normal range. CA 19-9 has been shown to be raised in pancreatic adenocarcinomas (most), gastric carcinomas (50%), and colorectal carcinomas (30%). Non-cancerous conditions can also affect CA 19-9 levels, including liver conditions, bile duct problems, and inflammatory digestive disorders.
Genetic variation plays a significant role in CA 19-9 production, with approximately 5-10% of the population being "Lewis negative," meaning they naturally produce little or no CA 19-9 regardless of their health status. This genetic variation explains why doctors consider individual baselines when interpreting results.
Age, gender, and other individual factors can influence CA 19-9 levels, though these variations are typically modest compared to changes caused by specific health conditions requiring medical attention.
CA 19-9's Role in Health Monitoring
CA 19-9 excels as a monitoring tool for people undergoing treatment for diseases such as cancer, helping doctors assess treatment effectiveness and detect changes that might require medical attention. The test provides objective measurements that help guide treatment decisions and ongoing care planning.
CA 19-9 monitoring also provides reassurance when levels remain stable or decline following treatment, offering objective evidence that medical interventions are working as intended.
CA 19-9's Role in Health Monitoring
CA 19-9 excels as a monitoring tool for people undergoing treatment for diseases such as cancer, helping doctors assess treatment effectiveness and detect changes that might require medical attention. The test provides objective measurements that help guide treatment decisions and ongoing care planning.
CA 19-9 monitoring also provides reassurance when levels remain stable or decline following treatment, offering objective evidence that medical interventions are working as intended.
CA 19-9's Role in Health Monitoring
CA 19-9 excels as a monitoring tool for people undergoing treatment for diseases such as cancer, helping doctors assess treatment effectiveness and detect changes that might require medical attention. The test provides objective measurements that help guide treatment decisions and ongoing care planning.
CA 19-9 monitoring also provides reassurance when levels remain stable or decline following treatment, offering objective evidence that medical interventions are working as intended.
CA 19-9's Role in Health Monitoring
CA 19-9 excels as a monitoring tool for people undergoing treatment for diseases such as cancer, helping doctors assess treatment effectiveness and detect changes that might require medical attention. The test provides objective measurements that help guide treatment decisions and ongoing care planning.
CA 19-9 monitoring also provides reassurance when levels remain stable or decline following treatment, offering objective evidence that medical interventions are working as intended.
Understanding Your Results
Normal levels: Less than 37 kU/L
Normal values indicate typical cellular activity, whilst elevated levels warrant medical evaluation within your individual clinical context. Elevated levels require careful interpretation considering your medical history, current symptoms, and whether you're being monitored for specific conditions. Your doctor will evaluate results alongside other clinical information to determine appropriate next steps, as there is a high incidence of false positive and false negative results with most tumour markers. This is why doctors use CA 19-9 strategically rather than as a standalone diagnostic tool.
Understanding Your Results
Normal levels: Less than 37 kU/L
Normal values indicate typical cellular activity, whilst elevated levels warrant medical evaluation within your individual clinical context. Elevated levels require careful interpretation considering your medical history, current symptoms, and whether you're being monitored for specific conditions. Your doctor will evaluate results alongside other clinical information to determine appropriate next steps, as there is a high incidence of false positive and false negative results with most tumour markers. This is why doctors use CA 19-9 strategically rather than as a standalone diagnostic tool.
Understanding Your Results
Normal levels: Less than 37 kU/L
Normal values indicate typical cellular activity, whilst elevated levels warrant medical evaluation within your individual clinical context. Elevated levels require careful interpretation considering your medical history, current symptoms, and whether you're being monitored for specific conditions. Your doctor will evaluate results alongside other clinical information to determine appropriate next steps, as there is a high incidence of false positive and false negative results with most tumour markers. This is why doctors use CA 19-9 strategically rather than as a standalone diagnostic tool.
Understanding Your Results
Normal levels: Less than 37 kU/L
Normal values indicate typical cellular activity, whilst elevated levels warrant medical evaluation within your individual clinical context. Elevated levels require careful interpretation considering your medical history, current symptoms, and whether you're being monitored for specific conditions. Your doctor will evaluate results alongside other clinical information to determine appropriate next steps, as there is a high incidence of false positive and false negative results with most tumour markers. This is why doctors use CA 19-9 strategically rather than as a standalone diagnostic tool.
The Takeaway
CA 19-9 serves as your digestive system's specialised monitoring protein, also known as a ‘tumour marker’, providing valuable information for tracking specific health conditions and treatment progress. When it is raised, it may warrant further testing. Understanding CA 19-9 results requires considering your individual health context, baseline levels, and the specific reasons for testing.
The Takeaway
CA 19-9 serves as your digestive system's specialised monitoring protein, also known as a ‘tumour marker’, providing valuable information for tracking specific health conditions and treatment progress. When it is raised, it may warrant further testing. Understanding CA 19-9 results requires considering your individual health context, baseline levels, and the specific reasons for testing.
The Takeaway
CA 19-9 serves as your digestive system's specialised monitoring protein, also known as a ‘tumour marker’, providing valuable information for tracking specific health conditions and treatment progress. When it is raised, it may warrant further testing. Understanding CA 19-9 results requires considering your individual health context, baseline levels, and the specific reasons for testing.
The Takeaway
CA 19-9 serves as your digestive system's specialised monitoring protein, also known as a ‘tumour marker’, providing valuable information for tracking specific health conditions and treatment progress. When it is raised, it may warrant further testing. Understanding CA 19-9 results requires considering your individual health context, baseline levels, and the specific reasons for testing.
References
Gloucestershire Hospitals NHS Foundation Trust. (2017). CA 19-9 Tumour Marker Clinical Guidelines. NHS Foundation Trust Laboratory Medicine.
Sheffield Laboratory Medicine. (2024). CA19-9 Testing Protocols and Reference Ranges. NHS Foundation Trust Clinical Services.
North Bristol NHS Trust. (2024). CA 19-9 Laboratory Information and Clinical Use. NHS Foundation Trust Pathology Services.
Association for Clinical Biochemistry & Laboratory Medicine. (2018). CA19-9 Clinical Practice Guidelines. ACB National Laboratory Medicine Handbook.
References
Gloucestershire Hospitals NHS Foundation Trust. (2017). CA 19-9 Tumour Marker Clinical Guidelines. NHS Foundation Trust Laboratory Medicine.
Sheffield Laboratory Medicine. (2024). CA19-9 Testing Protocols and Reference Ranges. NHS Foundation Trust Clinical Services.
North Bristol NHS Trust. (2024). CA 19-9 Laboratory Information and Clinical Use. NHS Foundation Trust Pathology Services.
Association for Clinical Biochemistry & Laboratory Medicine. (2018). CA19-9 Clinical Practice Guidelines. ACB National Laboratory Medicine Handbook.
References
Gloucestershire Hospitals NHS Foundation Trust. (2017). CA 19-9 Tumour Marker Clinical Guidelines. NHS Foundation Trust Laboratory Medicine.
Sheffield Laboratory Medicine. (2024). CA19-9 Testing Protocols and Reference Ranges. NHS Foundation Trust Clinical Services.
North Bristol NHS Trust. (2024). CA 19-9 Laboratory Information and Clinical Use. NHS Foundation Trust Pathology Services.
Association for Clinical Biochemistry & Laboratory Medicine. (2018). CA19-9 Clinical Practice Guidelines. ACB National Laboratory Medicine Handbook.
References
Gloucestershire Hospitals NHS Foundation Trust. (2017). CA 19-9 Tumour Marker Clinical Guidelines. NHS Foundation Trust Laboratory Medicine.
Sheffield Laboratory Medicine. (2024). CA19-9 Testing Protocols and Reference Ranges. NHS Foundation Trust Clinical Services.
North Bristol NHS Trust. (2024). CA 19-9 Laboratory Information and Clinical Use. NHS Foundation Trust Pathology Services.
Association for Clinical Biochemistry & Laboratory Medicine. (2018). CA19-9 Clinical Practice Guidelines. ACB National Laboratory Medicine Handbook.
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