If a patient is suspected of having a tumor, the doctor will prescribe a number of standard examinations.
The diagnosis of a malignant lesion can be made only on the basis of an assessment of changes in the biopsy - the immunohistochemical study( IHC) is considered one of the most reliable methods of detecting tumor cells.
What is immunohistochemical examination?
The essence of immunohistochemical research is the study under a microscope of samples of biological material, that is, tissues obtained by biopsy.
Prefabricated tissues are treated with certain specific antibodies.
Cancer and the cancer cells themselves have been the objects of comprehensive research for several decades.
In the course of these studies, scientists were able to establish that tumor cells produce specific proteins or else they are called antigens.
These proteins have the ability to bind to antibodies. It is on this that the principle of IHH is constructed - the tissue taken from the patient for examinatio
n is treated with a number of standard antibodies and the study is carried out under a microscope.
If antibodies interact with cancer cells, then they have the property of fluorescence, that is, there is a glow that differs in different wavelengths. That is, if such a change in the biopsy specimen is found, then it is possible to exhibit a malignant formation with greater probability.
To date, antibodies have been developed and actively used for most of the most common neoplasms.
Immunohistochemical study allows:
- To determine the type of neoplasm and its subspecies.
- Determine how widespread the primary cancerous body is.
- Determine the source of metastases if the biopsy specimen is derived from secondary cancer sites.
- To evaluate how effectively the treatment of patients with cancer is conducted.
- To establish the stage of malignant neoplasm.
- To elucidate the proliferation of tumors, that is, to establish the rate of growth of tumors.
The IHC method can be used to study virtually any tissue in the human body. This type of research is assigned mainly if there is a suspicion of the development of the tumor process.
Immunohistochemical study used:
- To determine the type of primary, mainly single, neoplasm.
- To detect metastases.
- When it is necessary to determine the prognosis of development and course of tumors.
- As a method of studying receptors for a number of hormones.
- To determine the type of lymphoproliferative conditions.
- For detection of microorganisms.
No contraindications to IHC.This analysis can not be carried out only if there are insurmountable difficulties in the collection of damaged tissue samples.
How is the analysis done? The
IGH is carried out in several stages, the very first is the dolorboron, that is, the sampling of tissues for analysis.
A sample is obtained by biopsy, in some cases it is possible to pinch off a piece of tissue or remove it when carrying out an endoscopic or surgical procedure.
How biological material will be obtained depends on the localization of the tumor and its type. The collected material is placed in formalin and only then sent to the laboratory center.
In the laboratory, the tissue sample undergoes several changes:
- The material is degreased and filled with paraffin. Thus, histological blocks are obtained, they can be stored forever, therefore, IHH can be repeated if necessary.
- The next stage of microtemping is to obtain the finest sections with a width of up to 1.0 μm from the paraffin blocks. Sections are distributed on special glasses.
- The resulting sections are stained with immunohistochemical preparations, that is, solutions of antibodies at a certain concentration. It can be used to study a small panel - it includes 5 kinds of antibodies. A large panel contains 6 to dozen types of markers. Which antibodies will interact with tumor cells depends on the type of neoplasm expected.
The results of the IHC are known within 7-15 days.
IGH in breast cancer
Certain immunohistochemical markers were identified for the detection of breast cancer. If there is a suspicion of malignant education, the number of receptors such as estrogen and progesterone is mandatory.
Excess of these hormones provokes the growth of malignant formation and affects the appearance of metastases. IHH for the expression of progesterones and estrogens allows you to more accurately establish the stage of the disease and find out whether this shows whether hormonal treatment.
Tumors with a high concentration of hormones in most cases are not characterized by increased activity and are successfully treated with anti-hormonal drugs.
When carrying out IHC, it is necessary to determine such an indicator as Ki-67, it indicates the malignancy of the process. If Ki-67 breast cancer reaches only 15%, then the outcome of the disease is considered favorable.
At a level of 30%, they say a rapid rate of tumor development, the cessation of its growth occurs under the influence of chemotherapy. If the indicator is less than 30%, then the treatment of patients is carried out hormonal means.
Immunohistochemical examination is prescribed not only for malignant lesions of the breast, this study is informative when:
- Malignant diseases of the uterus.
- Pathological changes in reproductive function.
Immunohistochemical examination of endometrial tissue is prescribed:
- With frequent miscarriage.
- Patients with several unsuccessful IVF attempts.
- When diagnosing the chronic form of the endometrium.
IGH allows to establish whether there are cells that prevent conception. This analysis simultaneously determines how the receptors of the uterus tissue react to hormonal stimulation, if pathology is detected, this indicates changes in the endometrium - endometritis, hyperplasia, desynchronization of the process of differentiation of the endometrium.
It is these violations in two cases out of three that become the main causes of problems with conception and fetal bearing.
The selection of endometrial tissues depending on the pathology to be detected is carried out on different days of the cycle, the doctor must appoint a biopsy day. With the help of IHC, it is possible to establish cancers and the infection of several subspecies of HPV.
Explanation of the results
Examines the prepared samples by a pathologist, he must have a certificate of special preparation for the analysis by the IHC method.
In conclusion, the parameters of antibodies to which the tropicity of the test material is determined are taken out.
The morphological structure of the tissue is necessarily indicated, that is, the type of atypical cells and their number.
Identification of specific antigens indicates a type of cancer pathology. But it is necessary to take into account that the diagnosis is set only on the totality of the data of all diagnostic procedures. An oncologist can interpret the results of IHC.
Price of the study
The cost of an immunohistochemical test depends on how many antibodies are used in the analysis.
Video on how immunohistochemistry helps diagnose a malignant tumor: