This mastectomy specimen contains an infiltrating ductal carcinoma of the breast. A pathologist will use immunohistochemistry and fluorescent in-situ hybridization to detect markers which determine the optimal chemotherapy regimen for this patient.
(from
Greek ,
patos, "fate, harm"; and ,
-logia) is the study and
diagnosis of
disease through examination of
organs,
tissues,
bodily fluids, and whole bodies (
autopsies). The term also encompasses the related
scientific study of disease processes, called
General pathology.
Medical pathology is divided in two main branches,
Anatomical pathology and
Clinical pathology.
Veterinary pathology is concerned with animal disease whereas
Phytopathology is the study of plant diseases.
History of pathology
The History of pathology can be traced to the earliest application of the
scientific method to the field of
medicine, a development which occurred in the
Middle East during the
Islamic Golden Age and in
Western Europe during the
Italian Renaissance.
Early systematic human
infections were carried out by the
Ancient Greek physicians
Herophilus of Chalcedon and
Erasistratus of Chios in the early part of the third century BC. The first physician known to have made
postmortem dissections was the
Arabian physician
Avenzoar (1091–1161).
Rudolf Virchow (1821–1902) is generally recognized to be the father of microscopic pathology. Most early pathologists were also practicing
physicians or
surgeons.
General pathology
General pathology is also called investigative pathology, experimental pathology or theoretical pathology, is a broad and complex
scientific field which seeks to understand the mechanisms of injury to
cells and
tissues, as well as the body's means of responding to and repairing injury. Areas of study include cellular adaptation to injury,
necrosis,
inflammation,
wound healing and
neoplasia. It forms the foundation of pathology, the application of this knowledge to diagnose diseases in humans and
animals.
The term "general pathology" is also used to describe the practice of both
anatomical and
clinical pathology.
Pathology as a medical specialty
Pathologists are physicians who diagnose and characterize disease in living patients by examining
biopsies or
bodily fluid. The vast majority of
cancer diagnoses are made or confirmed by a pathologist. Pathologists may also conduct
autopsies to investigate causes of death. Pathology is a core discipline of
medical school and many pathologists are also teachers. As managers of
medical laboratories, pathologists play an important role in the development of
Laboratory information systems. Although the medical practice of pathology grew out of the tradition of
investigative pathology, most modern pathologists do not perform original research.
Pathology is a unique medical specialty in that pathologists typically do not see
patients directly, but rather serve as consultants to other physicians (often referred to as "clinicians" within the pathology community). To be licensed, candidates must complete medical training, an approved residency program and be certified by an appropriate body. In the US, certification is by the
American Board of Pathology or the American Osteopathic Board of Pathology. The organization of subspecialties within pathology varies between nations, but usually includes
anatomical pathology and
clinical pathology.
Anatomical pathology
thumb|200px|Pathologist instructor and students of anatomical pathology.Anatomical pathology (
Commonwealth) or Anatomic pathology (
U.S.) is a medical specialty that is concerned with the diagnosis of disease based on the
gross,
microscopic, chemical, immunologic and
molecular examination of
organs,
tissues, and whole bodies (
autopsy).
Anatomical pathology is itself divided in subspecialties, the main ones being
surgical pathology,
cytopathology and
forensic pathology. To be
licensed to practice pathology, one has to complete
medical school and secure a license to practice medicine. An approved
residency program and certification (in the U.S., the
American board of Pathology or the American Osteopathic Board of Pathology) is usually required to obtain employment or hospital privileges.
Anatomical pathology is one of two branches of pathology, the other being
clinical pathology, the diagnosis of disease through the
laboratory analysis of
bodily fluids and/or tissues. Often, pathologists practice both anatomical and clinical pathology, a combination known as
general pathology. The distinction between anatomic and clinical pathology is increasingly blurred by the introduction of technologies that require new expertise and the need to provide patients and referring physicians with integrated diagnostic reports. Similar specialties exist in
veterinary pathology.
Clinical pathology
Clinical pathology is a medical specialty that is concerned with the diagnosis of disease based on the
laboratory analysis of
bodily fluids such as
blood and
urine, and tissues using the tools of
chemistry,
microbiology,
hematology and
molecular pathology. Clinical pathologists work in close collaboration with
medical technologists hospital administrations and referring physicians to ensure the accuracy and optimal utilization of laboratory testing.
Clinical pathology is one of the two major divisions of pathology, the other being
anatomical pathology. Often, pathologists practice both anatomical and clinical pathology, a combination sometimes known as general pathology.
Biomedical science which is a field of
science, must not be confused with
Pathology, a field of
medicine.
Forensic pathology
Forensic pathology is a branch of pathology concerned with determining the
cause of death by examination of a
cadaver. The
autopsy is performed by the pathologist at the request of a
coroner usually during the investigation of
criminal law cases and
civil law cases in some
jurisdictions. Forensic pathologists are also frequently asked to confirm the identity of a cadaver.
The word
forensics is derived from the Latin
forēnsis meaning
forum.
Veterinary pathology
Veterinary pathologists are
doctors of veterinary medicine who specialise in the
diagnosis of diseases through the examination of animal tissue and body fluids. Like for medical pathology, veterinary pathology is divided in two branches,
anatomical pathology and
clinical pathology. Veterinary pathologists are critical participants in the drug development process.
Plant pathology
Plant pathology (also phytopathology) is the scientific study of plant diseases caused by pathogens (infectious diseases) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like organisms, phytoplasmas, protozoa, nematodes and parasitic plants. Not included are insects, mites, vertebrate or other pests that affect plant health by consumption of plant tissues. Plant pathology also involves the study of pathogen identification, disease etiology, disease cycles, economic impact,
plant disease epidemiology,
plant disease resistance, how plant diseases affect humans and animals, pathosystem genetics, and management of plant diseases.
The
"Disease triangle" is a central concept of plant pathology
[George N. Agrios (1997) Plant Pathology fourth edition, Academic Press. New York.]. It is based on the principle that infectious diseases develop, or do not develop, based on three-way interactions between the host, the pathogen and environmental conditions.
Molecular pathology
Molecular pathology is an emerging discipline within pathology which is focused in the study and diagnosis of disease through the examination of molecules within organs, tissues or bodily fluids.
Molecular pathology shares some aspects of practice with both anatomic pathology and clinical pathology,
molecular biology,
biochemistry,
proteomics and
genetics, and is sometimes considered a "crossover" discipline.
It is multi-disciplinary in nature and focuses mainly on the sub-microscopic aspects of disease and unknown illnesses with strange causes
It is a scientific discipline that encompasses the development of molecular and genetic approaches to the diagnosis and classification of human tumours, the design and validation of predictive biomarkers for treatment response and disease progression, the susceptibility of individuals of different genetic constitution to develop cancer and the environmental and lifestyle factors implicated in carcinogenesis.
See also
