Anatomopathology: Definition, Structure, Pathophysiology, Pathology and Anatomo-Pathological Procedures

It is a unique medical discipline in the clinic, biology, and image.

It is an essential step for diagnosis, especially in cancer cases.

It uses many complementary techniques, such as molecular biology methods, chromogenic in situ hybridization, or fluorescence hybridization.

The demand for new diagnoses that use cytology and anatomy approaches increases rapidly.

These growing needs range from scanning, visualization, image management, annotation, quantification, and, finally, the generation of reports.

Pathological anatomy or anatomy pathology studies the structural alterations ( anatomical lesions ) of the body and its organs and tissues and how this relates to function and contributes to the development of the disease.

They cover the study of the normal and abnormal morphology of the body at macroscopic and microscopic levels.


The emphasis in anatomy is on understanding how the structure is related to the organism’s function. In pathology, it is about understanding the causes, the mechanisms of development, and the disease’s consequences.


Each body organ comprises four primary tissues: epithelial, connective, muscular, and nervous tissue.

However, the cells in these tissues can be formed differently when they are found in different organs.

The way how cells form a tissue can predict how that tissue works.

This is because the same patterns of structure and function are repeated throughout the body.

Some tissues provide rigid support to the structure, such as bone; others contract the general force of movement, like a skeletal muscle. Others form pockets that secrete fluids, such as the salivary glands.

Pathophysiology and pathology

Diseases occur because normal tissues are damaged or do something wrong.

Pathology and pathophysiology are the studies of malformed diseases and tissues with the hope of understanding their causes and possible treatments.

The pathology examines how a tissue has an abnormal shape.

Pathophysiology examines how a tissue abnormally produces molecules and fluids.

Neither pathology nor physiopathology would be possible without histology since a researcher would not recognize the abnormal without knowing what is expected.

Pathological anatomy is a discipline that combines fundamental sciences and clinical practice.

The information acquired by studying the morphological changes of organs, tissues, and cells induced by pathological processes and human diseases serves as a basic knowledge for further developing essential diagnostic and treatment skills.

The general sections (associated with pathological processes) and systemic and nosological (associated with diseases) sections of the pathological anatomy are studied.

Activities and procedures Anatomo-Pathological


biopsy is a medical procedure in which a tissue sample is taken from a patient to examine and diagnose a disease or medical condition.

Many different biopsy procedures depend on the location of the tissue being investigated, which include:

  • Bone marrow biopsy: A small sample of bone marrow (usually hip) is removed through a thin needle. This type of biopsy helps diagnose diseases such as leukemia.
  • Colposcopy-directed biopsy: A colposcope is a small microscope used to examine a woman’s cervix while taking a tissue sample and helping to diagnose based on the Pap test results.
  • Endoscopic biopsy: The endoscope is a flexible tube that can be inserted into a hole (such as the mouth or anus) or through a small incision in the skin. Once the mass is reached, the cutting tools are threaded through the endoscope so that a tissue sample can be taken.
  • Needle biopsy: A small piece of the tumor is removed with a thin hypodermic needle. This can be done with or without local anesthesia. This type of biopsy can be used to diagnose liver or thyroid conditions.
  • Puncture biopsy: a unique tool is used to drill a hole through the upper layers of the skin. The anesthetic used can be local or topical. This type of biopsy can help diagnose various skin conditions.
  • Stereotactic biopsy: a series of x-rays help guide the surgeon’s needle to the lump. This type of biopsy is usually done when the node is difficult to see or feel.

Anatomical pathology and cytology

The DNA is extracted from the patient’s tissue; the hormone receptor assays are performed on paraffin-embedded tissues and fixed with formalin.

The tests are:

  1. Analysis of hormone receptors of all cases of breast carcinoma, such as estrogen, progesterone, and HER2 gene receptors.
  2. Amplification assays of the HER2 gene by in situ fluorescent hybridizations in selected cases of breast carcinoma, UroVysion FISH assay to help diagnose recurrent bladder carcinoma in urine samples.
  3. Microsatellite instability assays detect colorectal carcinoma patients due to possible inherited genetic defects.
  4. Quantifying DNA in hidatidaphic moles and subtyping genital and cervical lesions for the human papillomavirus to identify patients at high risk of developing cervical cancer.
  5. Diagnosis of skin diseases, neoplasms of soft and hematopoietic tissues, and systemic diseases that can affect the skin, thanks to histology and routine optical microscopy.


This includes the analysis of amniotic fluid, chorionic villi, bone marrow, peripheral blood, fetal blood, solid tumors, and other tissues.

Tests include chromosomal analysis of amniotic fluids, bone marrow aspirates, chorionic villus biopsies, solid neoplastic tissue, oncological blood, peripheral blood, products of conception, and cytogenetic tests.

Also, oncological, prenatal tests, special stains to identify chromosomal variants, tissue culture of the patient to provide cells for analysis and biochemical tests, fluorescent in situ hybridization tests, complete chromosomal markers or chromosomes of unknown origin.

These procedures help detect chromosomal abnormalities associated with microdeletion and microduplication syndromes, hematological disorders, and detection of prenatal aneuploidy.

Electron microscopy

This involves fixing the tissue, embedding the sample in epoxy polymer, sectioning the tissue at approximately 700 Angstroms, staining with heavy metals, examining the pieces, and recording images representative of the tissue.

Electron microscopy can be seen as an extension of routine optical diagnostic techniques.