Biopsy, Types of Biopsy, and Indications

Biopsy

Biopsy:

A biopsy is a research method in which cells or tissues (biopsy) are taken from the body for diagnostic or research purposes. A biopsy is a mandatory method of confirming the diagnosis in case of suspected oncological diseases.

The term "biopsy" was introduced into medical practice by the French dermatologist Ernest Besnier in 1879.

Types of Biopsy:

According to the method of obtaining material

Taking material for histological examination

• Excisional biopsy - taking the entire pathological formation for the study.
• Incisional biopsy - taking for the study of a part of a pathological formation or a diffusely altered organ.
• Punch biopsy - using biopsy forceps (punch-biopsy)
• Trephine biopsy - taking a column of dense tissue using a hollow tube with a pointed edge - a trephine. It is used for bone biopsy and solid tumors.
• Core (core-biopsy, core-biopsy, cutting biopsy) - taking a column of material from soft tissues using a special trephine, consisting of a harpoon system and a hollow tube with a pointed edge.
• Scarification (surface) biopsy (shaving biopsy) - taking material by cutting off a thin layer of tissue from the surface of the formation, used for biopsy of pathological skin formations.
• Loop biopsy – a sampling of material with a loop using a coagulator in tissue cutting mode or a radiofrequency surgical apparatus. It is used in ENT, gynecology, and endoscopic studies.

Taking material for cytological examination

• An imprint from a pathological formation (erosion, ulcer) - the material is transferred to a glass slide by applying it to the ulcerated surface.
• A smear imprint from a pathological formation - the material is scraped off from a pathological formation with a spatula, scalpel, or cytobrush and then transferred to a glass slide.
• Fine needle aspiration biopsy (FNAB) - taking material for research, usually using a puncture needle and syringe. It is used both for the biopsy of cystic formations and solid tumors.
• Aspiration biopsy is a variant of FNAB of liquid formations: cysts, fluid intake from the pleural or abdominal cavity.

By type of accuracy control:

• Classic biopsy
• Targeted biopsy
• Endoscopic
• Biopsy under ultrasound guidance
• Biopsy under X-ray control
• Stereotactic biopsy

Goal and Objective:

If it is necessary to determine the cellular makeup of the tissue, a biopsy is the most dependable research technique. You can precisely ascertain the cellular composition of the material under study by taking tissues and then examining them under a microscope. A biopsy is a study that is included in the diagnostic minimum for suspected cancer and is supplemented by other research methods, such as x-ray, endoscopic, and immunological.

 An essential circumstance that determines the need for a biopsy is the need to determine the tactics of treatment for oncological diseases. The treatment of oncological diseases requires the implementation of traumatic, often disabling interventions: surgical operations, radiation therapy, and the introduction of toxic chemotherapy drugs, which do not allow starting treatment without reliable confirmation of the diagnosis, which is a histological or cytological examination of biopsy specimens.

 For example, with rectal cancer, located in the lower sections, a radical method of treatment is to perform abdominoperineal extirpation of the rectum - an operation that involves the removal of the rectum and the formation of a colostomy (unnatural anus). In the absence of clear confidence in the diagnosis, such an operation cannot be performed. If after the operation it turns out that there was no malignant tumor, the question of the useless performance of a traumatic intervention will naturally arise. The same goes for breast cancer, stomach cancer, lung cancer, and other malignant tumors.

Indications of biopsy:

A biopsy is required if a disease is suspected, the diagnosis of which cannot be reliably or fully established using other research methods. Traditionally, such diseases are oncological (tumor). Today, however, the biopsy is widely used in the diagnosis of non-neoplastic diseases. First of all, in gastroenterology (detection of microscopic features of inflammatory and precancerous diseases of the esophagus, stomach, small and large intestine, which largely determines further tactics and therapy) and gynecology (definition of endocrine diseases and causes of infertility by scrapings from the uterine cavity, inflammatory and precancerous diseases of the cervix). In addition, a histological examination is required to establish the characteristics of the course and severity of the lesion (and, consequently, for the prognosis and correction of therapy) in diseases of certain organs (liver, kidneys, nervous and muscular systems, as well as some vascular lesions). However, the diagnosis of these conditions is limited by the technical capabilities of taking and examining the material, which is usually performed only in specialized institutions and is not available to the district or regional centers.

Histological examination:

Histological examination is the examination of tissues under a microscope. With the help of special solutions ( histological wiring ), a piece of tissue is dehydrated and made fat-soluble for subsequent impregnation with paraffin in special forms, which at room temperature are solid cubes. Sections are made using a microtome with a built-in very sharp knife that can remove layers as thin as 3 micrometers. Subsequently, the sections are mounted on glass and they are prepared for staining (for different colors, the preparation methods may vary, but in most cases, all paraffin is removed from the sections along with the rest of the fats and soaked in ethanol to allow the diffusion of water-soluble substances). And only after that, they are stained with various dyes, which makes it possible to make cells and their elements visible under a microscope, as well as various elements of the intercellular substance of tissues. Specialist (clinical pathologist - a common term in the West, pathologist - a name established in the domestic nomenclature of specialties, pathologist and path histologist - an informal designation widely used among pathologists in the Russian language) based on the results of examining an object under a microscope, gives a conclusion on the basis of which a clinical diagnosis is formed or makes a final diagnosis. There is also a method of urgent histological examination when the material is taken during the operation, and it is necessary to quickly resolve the issue of what the found formation is, and determine the volume and tactics of further surgical intervention. The essence of the method lies in ultra-fast (total study time does not exceed 30 minutes, with the standard method the total study time takes at least 3 days) low-temperature freezing of the drug in water, without histological posting (that is, bringing it to a paraffin block), further procedure is standard. The disadvantage of this method is the lower quality of the resulting drug, and hence the reliability of the conclusion.

Cytological Examination:

Fundamentally, a cytological study differs from a histological one in that it does not conduct a tissue study, but a cell study. So, it is far from always possible to take a piece of tissue, and it is not always necessary. For example, in gynecology, one of the most frequently performed procedures is a smeared print from the surface of the cervix. Such a study is performed with the aim of early detection or exclusion of the presence of precancerous diseases. In this case, only cells are taken from the surface of the suspicious formation. After processing and staining the specimen, the morphologist examines the resulting cells and gives a conclusion about the nature of this formation. Cytological.