Positron emission tomography, or PET for short, is a state-of-the-art examination method that allows doctors to see not only what the body looks like, but also how it works. It is a nuclear medicine procedure and is often combined with other techniques such as MRI or CT.

What is a PET and how does it work?

PET is like a window into our body’s metabolic processes. It uses weak radioactive substances, so-called tracers, which are injected into the body. These tracers are usually linked to a type of sugar (glucose) because many cells – especially cancer cells or inflamed tissue – need sugar as an energy source. Once the tracer is in the body, it emits tiny particles called positrons. These positrons collide with electrons in the body, and this “encounter” produces energy in the form of flashes of light, which are recorded by a special camera. A computer then converts these signals into images that show where there is a lot of activity in the body.

The special thing about PET is that it not only shows structures such as organs or bones, but also their function. For example, it can show which areas of the brain are active during a task or where cancer cells are multiplying particularly strongly. This makes it a unique tool in medicine.

The role of PET in interaction with laboratory medicine

Laboratory medicine deals with the examination of blood, urine or tissue samples in order to detect diseases or monitor the state of health. Typical tests measure blood sugar, inflammation levels or tumor markers, for example. But sometimes these tests only provide clues without telling the whole story. This is where PET comes into play: it complements laboratory results by showing what is happening in the body at a cellular level.

Let’s take an example: a blood test shows elevated tumor markers that could indicate cancer. But where is the tumor located and how active is it? A PET scan can reveal exactly that. It shows where the tracer accumulates, i.e. where cells consume particularly high levels of sugar – a sign of cancer or metastases. Laboratory medicine then provides additional details, for example by analyzing tissue samples taken with the help of the PET images. This provides a complete picture of the disease.

PET is also valuable for heart disease or neurological problems such as Alzheimer’s disease. It can show which areas of the heart are well supplied with blood or where in the brain deposits are damaging the nerve cells. This information helps laboratory physicians to carry out specific tests to confirm the diagnosis or adjust the therapy.

The importance of PET in Germany

In Germany, PET is an integral part of modern medicine, even if it is not used as frequently as MRI or CT because it is more expensive and more complex. Nevertheless, it has proven to be indispensable in certain areas, especially in oncology (cancer medicine), neurology and cardiology. Many large clinics and specialized centers offer PET examinations, often in combination with a CT (PET/CT) in order to achieve even more precise results.

PET is an enormous support for laboratory medicine because it bridges the gap between laboratory results and physical reality. This is particularly important in Germany, where precision and early detection are very important. Health insurance companies usually cover the costs of a PET scan if it is medically necessary – for example in the search for metastases or to clarify unclear findings. This makes the technology accessible to many patients.

Another advantage: PET helps to monitor therapies. In cancer patients, it can show whether chemotherapy is working by comparing the metabolism of tumor cells before and after treatment. Laboratory physicians can use this data to evaluate blood values or tumor markers in context and adjust the treatment if necessary. This saves time and increases the chances of success.

Challenges and the future

Despite its advantages, PET also has its limitations. The tracers have to be prepared shortly before the examination because they decompose quickly – this requires special laboratories close to the clinic. In addition, radiation exposure, even if it is low, is an issue that patients and doctors are concerned about. In laboratory medicine, this means that PET is often only used selectively when other methods are not sufficient.

However, the future of PET in Germany looks very promising. New tracers are being developed that can visualize even more specific processes in the body, such as inflammation or immune reactions. The combination with artificial intelligence could also improve the evaluation of the images and make collaboration with laboratory medicine even closer.

Conclusion

Positron emission tomography is a powerful tool that enhances diagnoses in conjunction with laboratory medicine. It provides insights into the functions of the body that would not be possible with blood tests alone, helping to diagnose and treat diseases such as cancer, heart problems or Alzheimer’s more accurately. In a country known for its high-quality medicine, PET is a key to modern, patient-oriented care. It shows how technology and laboratory craftsmanship can work together to help people – precisely, gently and with an eye to the future.

Editorial office: X-Press Journalistenbüro GbR

Gender note. The personal designations used in this text always refer equally to female, male and diverse persons. Double/triple references and gendered designations are avoided for the sake of better readability ected.