ImmunohistochemistryImmunohistochemistry (IHC) is the most common application of immunostaining. It involves the process of selectively identifying antigens (proteins) in cells of a tissue section by exploiting the principle of antibodies binding specifically to antigens in biological tissues. IHC takes its name from the roots "immuno", in reference to antibodies used in the procedure, and "histo", meaning tissue (compare to immunocytochemistry). Albert Coons conceptualized and first implemented the procedure in 1941.
Medical diagnosisMedical diagnosis (abbreviated Dx, Dx, or Ds) is the process of determining which disease or condition explains a person's symptoms and signs. It is most often referred to as diagnosis with the medical context being implicit. The information required for diagnosis is typically collected from a history and physical examination of the person seeking medical care. Often, one or more diagnostic procedures, such as medical tests, are also done during the process. Sometimes the posthumous diagnosis is considered a kind of medical diagnosis.
Frozen section procedureThe frozen section procedure is a pathological laboratory procedure to perform rapid microscopic analysis of a specimen. It is used most often in oncological surgery. The technical name for this procedure is cryosection. The microtome device that cold cuts thin blocks of frozen tissue is called a cryotome. The quality of the slides produced by frozen section is of lower quality than formalin fixed paraffin embedded tissue processing. While diagnosis can be rendered in many cases, fixed tissue processing is preferred in many conditions for more accurate diagnosis.
Fixation (histology)In the fields of histology, pathology, and cell biology, fixation is the preservation of biological tissues from decay due to autolysis or putrefaction. It terminates any ongoing biochemical reactions and may also increase the treated tissues' mechanical strength or stability. Tissue fixation is a critical step in the preparation of histological sections, its broad objective being to preserve cells and tissue components and to do this in such a way as to allow for the preparation of thin, stained sections.
HistologyHistology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures visible without a microscope. Although one may divide microscopic anatomy into organology, the study of organs, histology, the study of tissues, and cytology, the study of cells, modern usage places all of these topics under the field of histology.
CytopathologyCytopathology (from Greek κύτος, kytos, "a hollow"; πάθος, pathos, "fate, harm"; and -λογία, -logia) is a branch of pathology that studies and diagnoses diseases on the cellular level. The discipline was founded by George Nicolas Papanicolaou in 1928. Cytopathology is generally used on samples of free cells or tissue fragments, in contrast to histopathology, which studies whole tissues. Cytopathology is frequently, less precisely, called "cytology", which means "the study of cells".
Anatomical pathologyAnatomical pathology (Commonwealth) or Anatomic pathology (U.S.) is a medical specialty that is concerned with the diagnosis of disease based on the macroscopic, microscopic, biochemical, immunologic and molecular examination of organs and tissues. Over the 20th century, surgical pathology has evolved tremendously: from historical examination of whole bodies (autopsy) to a more modernized practice, centered on the diagnosis and prognosis of cancer to guide treatment decision-making in oncology.
StainingStaining is a technique used to enhance contrast in samples, generally at the microscopic level. Stains and dyes are frequently used in histology (microscopic study of biological tissues), in cytology (microscopic study of cells), and in the medical fields of histopathology, hematology, and cytopathology that focus on the study and diagnoses of diseases at the microscopic level. Stains may be used to define biological tissues (highlighting, for example, muscle fibers or connective tissue), cell populations (classifying different blood cells), or organelles within individual cells.
Acute lymphoblastic leukemiaAcute lymphoblastic leukemia (ALL) is a cancer of the lymphoid line of blood cells characterized by the development of large numbers of immature lymphocytes. Symptoms may include feeling tired, pale skin color, fever, easy bleeding or bruising, enlarged lymph nodes, or bone pain. As an acute leukemia, ALL progresses rapidly and is typically fatal within weeks or months if left untreated. In most cases, the cause is unknown. Genetic risk factors may include Down syndrome, Li–Fraumeni syndrome, or neurofibromatosis type 1.
AutopsyAn autopsy (post-mortem examination, obduction, necropsy, or autopsia cadaverum) is a surgical procedure that consists of a thorough examination of a corpse by dissection to determine the cause, mode, and manner of death; or the exam may be performed to evaluate any disease or injury that may be present for research or educational purposes. For animals, the term necropsy is generally reserved. Autopsies are usually performed by a specialized medical doctor called a pathologist.
BiopsyA biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a disease. The tissue is then fixed, dehydrated, embedded, sectioned, stained and mounted before it is generally examined under a microscope by a pathologist; it may also be analyzed chemically. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy.
PathologyPathology is the study of the causes and effects of disease or injury. The word pathology also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when used in the context of modern medical treatment, the term is often used in a narrower fashion to refer to processes and tests that fall within the contemporary medical field of "general pathology", an area which includes a number of distinct but inter-related medical specialties that diagnose disease, mostly through analysis of tissue and human cell samples.
HaematoxylinHaematoxylin or hematoxylin (ˌhiːməˈtɒksᵻlᵻn), also called natural black 1 or C.I. 75290, is a compound extracted from heartwood of the logwood tree (Haematoxylum campechianum) with a chemical formula of C16H14O6. This naturally derived dye has been used as a histologic stain, as an ink and as a dye in the textile and leather industry. As a dye, haematoxylin has been called palo de Campeche, logwood extract, bluewood and blackwood. In histology, haematoxylin staining is commonly followed by counterstaining with eosin.
EosinEosin is the name of several fluorescent acidic compounds which bind to and form salts with basic, or eosinophilic, compounds like proteins containing amino acid residues such as arginine and lysine, and stains them dark red or pink as a result of the actions of bromine on eosin. In addition to staining proteins in the cytoplasm, it can be used to stain collagen and muscle fibers for examination under the microscope. Structures that stain readily with eosin are termed eosinophilic.
Myocardial infarctionA myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops in one of the coronary arteries of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck or jaw. Often it occurs in the center or left side of the chest and lasts for more than a few minutes. The discomfort may occasionally feel like heartburn. Other symptoms may include shortness of breath, nausea, feeling faint, a cold sweat or feeling tired.
Medical laboratoryA medical laboratory or clinical laboratory is a laboratory where tests are conducted out on clinical specimens to obtain information about the health of a patient to aid in diagnosis, treatment, and prevention of disease. Clinical medical laboratories are an example of applied science, as opposed to research laboratories that focus on basic science, such as found in some academic institutions. Medical laboratories vary in size and complexity and so offer a variety of testing services.
Gross processingGross processing, "grossing" or "gross pathology" is the process by which pathology specimens undergo examination with the bare eye to obtain diagnostic information, as well as cutting and tissue sampling in order to prepare material for subsequent microscopic examination. Gross examination of surgical specimens is typically performed by a pathologist, or by a pathologists' assistant working within a pathology practice.
Hodgkin lymphomaHodgkin lymphoma (HL) is a type of lymphoma in which cancer originates from a specific type of white blood cell called lymphocytes, where multinucleated Reed–Sternberg cells (RS cells) are present in the patient's lymph nodes. The condition was named after the English physician Thomas Hodgkin, who first described it in 1832. Symptoms may include fever, night sweats, and weight loss. Often, nonpainful enlarged lymph nodes occur in the neck, under the arm, or in the groin. Those affected may feel tired or be itchy.
