NSE

NSE (neuron-specific enolase) is an enzyme from nerve and neuroendocrine cells that is measured in blood as a tumour marker. It is used primarily in small-cell lung cancer, neuroblastoma and some neuroendocrine tumours, mainly for monitoring disease and treatment effects. It is not a test for detecting cancer in healthy people.

Who the test is intended for

• people with small-cell lung cancer, before treatment as a baseline and subsequently during follow-up;
• children with neuroblastoma, a childhood tumour, alongside urine tests and imaging, as assessed by a paediatric oncologist;
• people with a neuroendocrine tumour, for example of the pancreas or bowel, alongside other markers, most often chromogranin A;
• people being treated for these tumours, to monitor treatment effects and possible disease recurrence.

What NSE is and what it shows

Enolase is an enzyme involved in obtaining energy from glucose and exists in several forms. The forms characteristic of nerve and neuroendocrine cells (isoenzymes γγ and αγ) are called neuron-specific enolase. Tumours arising from these cells may release greater amounts of NSE into the blood.

In small-cell lung cancer, the NSE level is usually higher the more extensive the disease and falls after successful treatment. A renewed rise during follow-up may warn of disease recurrence. NSE does not show where the tumour is located or establish a diagnosis: this is established through imaging and biopsy.

Other markers are used more often for other types of lung cancer, such as CYFRA 21-1. NSE is not recommended for screening healthy people, because it can be elevated without cancer and normal in people who have a tumour. We describe the lung cancer signs to watch for in the article Early symptoms of lung cancer.

Preparation and sample

NSE is measured in blood from a vein, and you do not need to fast. If you take biotin (for example, hair and nail supplements), state this at blood collection. NSE is also found in red blood cells and platelets, so damage to these cells in the sample (haemolysis) falsely elevates the result. The sample must therefore be processed soon after collection. If NSE is monitored over a longer period, it is best to measure it in the same laboratory, because results from different methods cannot be compared directly.

How the NSE report is interpreted

The reference interval depends on the method and is printed on the report. For commonly used methods, the upper limit is around 16 µg/L. The report is interpreted by a doctor familiar with your disease and other results.

Elevated NSE

A slightly elevated value is most often not a sign of cancer. NSE can also rise with:

• sample haemolysis, a common reason for a falsely elevated result;
• haemolytic anaemia;
• more severe liver or kidney disease;
• brain injury, stroke, encephalitis or after an epileptic seizure;
• use of stomach-acid-reducing medicines from the proton pump inhibitor group.

The doctor will assess whether the test should be repeated using a new sample. In people being treated for cancer, the direction of change over multiple measurements is more important than a single value.

Normal NSE

A normal value does not rule out cancer. Some tumours, particularly at an early stage, do not raise NSE, so a normal report is not a reason to ignore symptoms.

How to arrange testing

You can have blood collected without an appointment or referral at one of our branches across Croatia (listed on the Contact page). Prices for all tests and panels are available in the service price list.

Frequently asked questions

For which cancers is NSE a tumour marker?

Primarily small-cell lung cancer and neuroblastoma, and it is also used in neuroendocrine tumours. In these diseases it helps assess disease extent, treatment effects and early detection of recurrence.

Does elevated NSE mean that I have cancer?

No. A common cause of a slightly elevated result is sample haemolysis, and NSE also rises in some liver, kidney and brain diseases. The doctor will consider the report alongside your symptoms and other tests, and repeat it if necessary.

Why does the doctor request a repeat NSE test?

Most often to rule out a falsely elevated result due to haemolysis or a temporary cause. In affected patients, NSE is also repeated for monitoring, because change over time matters more than a single value.

Should NSE be tested preventively?

It is not recommended. In healthy people without symptoms, the report more often confuses than helps. We explain what tumour markers are used for and when they make sense in the article Tumour markers.