If you suspect a malignant disease, you can only accurately diagnose after a series of examinations, the most important of which is a histological examination.
This method is understood as the microscopic study of a sample of tissue from the human body, obtained by biopsy or during an operation intervention. Histology should be prescribed to virtually all patients who have data for the development of not only malignant, but also benign tumors.
Objectives of the histological method of biopsy material research
Histological study is assigned to solve several problems at once. This analysis is required for:
- Confirm or disprove the alleged diagnosis.
- Definitions of the early stage of severe, including oncological diseases.
- Study of the course of the pathological process in dynamics.
- The correct choice of the technique of the operation when it is necessary to remove the neoplasm.
- Diffodiagnosis, which allows you to accurately divide two similar pathologies according to the
- Detection of metastases.
- Definitions of structural disorders formed in tissues during treatment.
For today, surgical intervention, irradiation sessions and chemotherapy for patients even with an already obvious course of malignant process without a previously performed histology are not prescribed.
Morphological study of biomaterial allows to select an adequate scheme of therapy for non-tumor processes.
Technique for performing the procedure
Patients with suspected malignant tumors are assigned a lifetime histological examination.
Biomaterial can be obtained from almost any place in the human body if necessary, using:
- Excisional biopsy of - tissue extraction by excision during surgery.
- Puncture biopsy. Puncture of the pathological focus is carried out and a piece of tissue is extracted with the help of a needle.
- Cutting biomaterial from distant organs.
- Spiked biopsy, that is, the missing special forceps with the necessary part of the pathological formation. This type of biopsy is possible with endoscopic examination - colonoscopy, esophagogastroduodenoscopy, bronchoscopy.
- Curettage - scraping of a pathological focus from organs with cavities or from those cavities that were formed as a result of malignant process.
- Aspiration biopsy - suction using a syringe secret from a hollow organ.
Method of obtaining a biopsy is basically determined in advance. During any procedure it is necessary to follow the rules of taking the material. If they are not fully complied with, then serious errors in the analysis are possible.
Often, the treating or operating physician plans a fence together with the pathologist, this doctor has a specialization in histology. The presence of the pathologist on the operation is also not forbidden, he will indicate the exact place of sampling of the tissue sample, determine its volume and method of fixation.
A small pathological focus is always excised completely, capturing a piece of healthy surrounding tissue 1-2 cm wide. If the operation is scheduled for a benign tumor, then the surgery is radical. Surgeons need to consider the cosmetic result of treatment when choosing the manipulation technique.
If it is technically impossible to remove the neoplasm completely, then the volume of the excised tissue sample should be as large as possible. It is necessary to take a piece of tissue where there is a zone of distinct pathology.
In the process of excision, one should not forget that traumatization of organs should be minimal. Correctly required and excise tissue, if such influences too change the structure of the sample, then it will be impossible to correctly carry out the histology.
When using an electron knife, the cut-off line must be at least 2 mm away from the main focus. The biomaterial should be treated with the utmost care - it is not allowed to crush it with fingers or tools. A sample of tissues is retained only for a healthy strip of biomaterial.
Not only the biomaterial specially sampled, but the organs and tissues removed during operations, are subjected to a histological examination of standards.
High demands are made for the documentation. The clinician should mark the biopsy, record the nature of the operation in the protocol, briefly describe the remote part of the organ or the tumor. The documents indicate which tissue samples and how many are sent to the pathoanatomical department.
The operating surgeon fills the direction of the histology, verifies the accuracy of the patient's data on the label on the laboratory container with a biopsy. The sticker should be on the side of the container itself, since it is not impossible to replace the lids in the same cans by mistake. Be sure to monitor the accuracy of filling all the graphs of the direction.
It is legible to write the patient's initials, his age, home address, necessarily mark the localization of the pathology, the connection of the biomaterial with the surrounding ligaments, muscles, organs.
If it is possible to immediately send the collected material to the study, it is not placed in the fixing solution. But it must be taken into account that the biopsy can not remain in the original form for a long time, as it dries up, and reliable analysis does not work. The smaller the tissue samples, the faster they lose moisture.
In the absence of the possibility of conducting histologists immediately biopsy at the site of its fence should be fixed. For fixation, 10% formalin is used, this solution should be 15 times larger than the piece of tissue sent to the analysis.
If the biopsy is large, it is recommended to make formalin for a better penetration into it, but so as not to change the quality of the properly collected material. Do not cut through the cuts and their number should be the most minimal.
The medical officer must carry or take the material to the pathological unit with the appropriate admission to this type of work. Sending and receiving material are documented.
Several samples of biomaterial from one focus are taken if the neoplasm is not uniform or there is no clear border of the tumor.
If the material for histology is taken according to all rules, then depending on the type of tissue being examined, the result can be ready in 5-15 days. The longest analysis of bone tissue.
The high accuracy of histological analysis is due to the fact that the morphological examination is performed under a microscope.
That is, the diagnostician has the opportunity to examine the biomaterial alive and determine pathological changes in it without the use of computer tomography or ultrasound.
Before direct examination of tissues under a microscope, it is stained with a special reagent, which allows you to clearly see all deviations from the norm. In the study of histological biologics, the doctor indicates microscopic changes, conducts an anatomical analysis of the revealed changes.
In conclusion, the doctor can give several variants of the results:
- An indicative answer is displayed when the received data are interpreted in favor of several diagnoses. That is, an additional diffodiagnosis is required.
- The final answer will allow an exact diagnosis based on the histology.
- The descriptive answer is left by the laboratory assistant if the biomaterial is insufficient or there is insufficient information about the nature of the disease.
In those cases when a biological preparation is not enough for study or the material is taken in such a way that there are more healthy tissues in it, a "false negative" result is exhibited."False positive" response is indicated if there are no clinico-laboratory data on the patient in the direction.
In order to avoid false analyzes, the joint work of the pathologist and the clinician is required. Doctors should jointly carefully discuss all identified changes in the analysis, study the patient's medical history.
In those cases where the histology is assigned for diagnostic purposes, in conclusion they give a microscopic description and write a nosological conclusion. When writing an opinion in Russia they are guided by a special medical nomenclature.
The distortion of the results of histology is affected by improper fixation and storage of biomaterial, gross errors in the collection of a biopsy. The accuracy of the analysis is influenced by the classification of the diagnostician. Normally, there should be no cellular changes in the test sample.
Examination of the cervix and endometrium
Gynecology often uses histological examination of endometrial tissue. It allows you to establish violations in the functioning of the ovaries and identify a number of diseases, they include and oncology.
In those patients in whom the menstrual cycle is not changed, diagnostic curettage is prescribed three days before the expected date of the critical days. With dysfunctional bleeding, the cleaning with the fence of the material for histology is performed without waiting for the bleeding to stop.
The resulting biomaterial is stained using hematoxylin or eosin. The analysis allows you to identify all the features and changes in the endometrium, determines the structure of the stroma and glandular cells.
Normally, the glands in the luteal phase of the menstrual cycle become saw-shaped and slightly widened.
Cell glands should have a light cytoplasm and pale nuclei, in the glands there must necessarily be a secret found in the norm.
If histological examination of scrapes from the cervix determines a slight change, this indicates the development of a benign tumor or inflammation. When a huge number of altered cells are detected, a precancerous condition or malignant process is not excluded.
Histology of the birthmark
The histology of the mole( nevus) is given, if there are signs indicating a possible malignant degeneration of the birthmark.
It can be pain in the place of the birthmark, a rapid increase in its size, the emergence of secretions or secretions, darkening of the pale nevi.
To obtain the biomaterial, it is necessary to remove the harassing birthmark completely.
Then it is placed in a fixing solution and sent to the study. The definition of atypical cells with a certain structure indicates a malignant degeneration. At a histological examination of a mole, it is possible to determine the type of formation, nature and stage of the inflammatory process.
The histology of the birthmark in special laboratory units is conducted in the direction of the doctor or at the request of the patient who appealed to them. Early detection of malignant cells will allow to carry out complex treatment in time, providing full recovery of the cancer patient.
Histology of the rectum
The material for histological examination of the rectum tissues is mainly taken during the colonoscopy. Two types of histological analysis are used:
- Urgent examination is performed within 30-40 minutes. It is carried out directly during the operation on the rectum, and the volume of the tumor being removed depends on the results obtained, together with the surrounding tissues.
- The planned study takes at least 5 days. Its data compared to urgent are more reliable.
Histology of the biopsy specimen from the rectum allows to determine whether there is malignant cell degeneration, both in the lower and upper parts of the organ.
The cost of histological examination of a biopsy material depends on the complexity of the analysis:
- The histology of the biomaterial of the first category ( here the biopsy material is taken when operating patients with nonspecifically occurring acute and chronic inflammation) costs between 2500-3000 thousand rubles.
- Histology of the third category ( in the absence of data for oncology) costs about 3500 rubles.
- The histology of the fourth category costs from 4 thousand rubles.