Diagnosis

CRP value in cancer

introduction

The C-reactive protein (CRP) is one of the so-called acute phase proteins and is formed by the liver as a non-specific response to inflammation processes in the body and released into the blood. It is used to attract cells of the immune system and to point them out to the focus of inflammation. In addition to infections, this reaction can also occur in the context of certain cancers, for example. However, it should be noted that the CRP value only shows a general activation of the immune system and is neither organ nor disease specific. Therefore, based on the CRP value alone, the exact cause can never be inferred and must always be assessed by the doctor in the overall context.

For general information about the blood count read below CRP value

Can a high CRP level indicate cancer?

An elevated CRP value is always noticeable and the cause must always be clarified. This can often be seen quickly, for example if the patient has an acute cold.

The CRP is one of the non-specific blood values and as such can give an indication of malignant diseases, but it can also have many other causes and must always be assessed in the overall context.

How can cancer increase CRP levels?

Certain types of cancer also increase the CRP value in some cases. The exact reason for this non-infectious increase is the subject of current research and has not yet been conclusively clarified. Various studies have shown that metastatic and very large tumors with a large tumor mass can increase CRP.One possible reason for this is that cancer can also lead to inflammation. Particularly in the case of very aggressive tumors, i.e. those whose cells extremely often double and thus grow rapidly, the tumor can no longer be supplied with sufficient blood and oxygen from a critical size, which leads to necrosis (tissue destruction). The body wants to get rid of this dead tissue quickly and sends so-called phagocytes to the site of the event, which in turn trigger an inflammatory reaction, which among other things increases the CRP. An example of such rapidly growing tumors are highly malignant lymphomas such as lymphoblastic lymphomas.
It was also observed that some tumor cells are able to produce CRP themselves and thus increase the value. The reason for this behavior is presumably that it improves the metabolism of the cancer cells and the tumor is better supplied with blood due to the newly growing vessels.
In addition, cancer of the immune system such as leukemia and lymphoma can lead to a pronounced impairment of the immune system as the tumor cells interfere with the formation of healthy immune cells in the bone marrow. The reduced immune competence often leads to infection with otherwise harmless pathogens such as certain bacteria or fungi, which in turn leads to an increase in CRP and fever. This is known as neutropenic fever and is acutely life-threatening if not detected quickly and treated with strong antibiotics.
In addition to the increase in CRP, cancer can also lead to other symptoms of an infection due to the mechanisms described, without the patient actually having an infection. These include, for example, fever, feeling sick or sweating profusely at night.

You can find an overview of different types of cancer at: Tumor diseases

What does the CRP value say about the progression of cancer?

If the CRP is elevated in the context of cancer, it can be used to assess the course in the context of a therapy, for example chemotherapy or radiation. Even after a successful surgical removal of the tumor, the CRP should decrease again if it was caused by the tumor. However, it must be noted that the CRP is very unspecific and can increase, especially during surgery and radiation therapy, due to the associated tissue damage. The CRP value is therefore not suitable as the sole marker to assess the course of the disease or the success of its treatment, but must always be assessed in the context of other blood values, possible imaging such as CT or MRI and of course the patient's symptoms. Depending on the tumor, further, specific follow-up checks should always be carried out, but these cannot be discussed in detail here.

Is CRP always elevated in cancer?

Cancer can be associated with increased CRP, but it is one of the non-specific laboratory values. It is therefore entirely possible that a malicious event will not lead to an increased CRP.

Which laboratory values can also be changed in cancer?

In many cancers, unspecific laboratory values are increased directly or indirectly due to the tumor. In addition to CRP, lactate dehydrogenase (LDH) is one such value. The LDH occurs in all cells. If many cells perish, as is the case with rapidly growing tumors, a lot of LDH gets into the blood and can be detected there. However, this can also happen with muscle injuries, liver disease, poisoning and many other processes. Further examples of such unspecific laboratory values are liver enzymes, pancreatic enzymes, number of blood cells and many more.

Tumor markers, on the other hand, are mostly proteins that can also be detected in healthy individuals, but whose increased concentration can indicate a specific tumor or its recurrence. Many of these tumor markers have already been discovered, well-known examples are alpha-1-fetoprotein in liver cell carcinomas and germ cell tumors or β-HCG in ovaries and testicular cancer.

However, it must also be noted that tumor markers alone are not proof of a tumor and must always be clarified further.

Read more about blood values and tumor markers

What other causes can an elevated CRP have?

A CRP value can basically indicate a malicious event, but the causes for an increase in CRP are extremely diverse and can also be comparatively harmless in nature. In general, CRP is the body's first reaction to all sorts of things that it tries to fight off with inflammation. As part of this process, the unspecific immune system is first activated, which leads to a so-called acute phase. Acute phase proteins, including CRP, are particularly produced by the liver and released into the blood. The CRP has the task of binding to pathogens such as bacteria and thereby marking them. In particular, macrophages (phagocytes) are attracted and activated as a result, which leads to further immune reactions. In addition, the CRP is involved in the control of the complement system, which is also part of the non-specific immune system.

In addition to the malignant diseases, frequent reasons for an increased CRP are: