What Is Histology?
Histology is the study of specially prepared cells and tissues under a microscope. Histopathology is the science of examining those cells and tissues to identify changes or abnormalities that might identify signs of disease.
A histopathologist is a type of doctor with highly specialized training who studies tissue samples, which are usually obtained through a biopsy. Histological analysis can help pathologists diagnose a disease, determine its severity, and even give a prognosis.
Histology is frequently used for cancer screening or diagnosis, but it can provide valuable information in all areas of medicine. It’s considered the “gold standard” for diagnosing many diseases.
If you need a histopathological exam, your doctor may talk to you about a biopsy and pathology report. A biopsy is a procedure to gather the tissue sample to be examined, and a pathology report describes the results of the examination.
Histology is also called microscopic anatomy or microanatomy because it’s a study of the body’s microscopic anatomy.
What Types of Tissues Are Studied?
Histopathology is a useful diagnostic tool for nearly every part of the body. Tissue samples can be taken during procedures like colonoscopy or biopsy. Histopathology can be used to diagnose infections, cancer, and diseases like ulcerative colitis, Crohn’s disease, and uterine fibroids.
Our bodies have four types of tissues:
- Epithelial tissue covers organs in a protective barrier, lines cavities and passageways, and forms glands.
- Muscle tissue contracts to make movements.
- Nervous tissue transmits impulses for communication and coordination between areas of the body.
- Connective tissue supports and holds cells and organs together. Soft tissues, bone, blood, and cartilage are all connective tissues.
Histopathologists are experts in all types of tissues and the diseases that can affect each.
How Are Tissue Samples Prepared?
Before examining a tissue sample under a microscope, the sample must be specially prepared to preserve it and make the cells more visible.
Tissue samples are preserved with chemicals, dehydrated, embedded in wax or plastic for support, sliced, and stained. Stains highlight important components of each tissue type to identify changes in the tissues and their functioning, abnormal deposits of minerals or protein, and accumulation of glycogen, fat, or carbs. There are many different types of stain to view various components of tissue.
How Long Do Results Take?
In some cases, a histopathologist can make a diagnosis right after the biopsy. In many cases, the sample requires several days of preparation before it can be examined. Still, others must be sent out to special laboratories. Each case may be different.
What Do Results Look Like?
The results of a histopathological examination are documented in a pathology report, which includes information like:
- A description of the tissue sample
- How it looks under the microscope
- A diagnosis or list of possible diagnoses (called a differential diagnosis)
- If there are cancer cells in the sample, what type, and how many
- If cancer is found, it may also contain information like the size and grade of the tumor and whether it has spread
- Comments from the histopathologist
The report is sent to the treating doctor, who will discuss the results with the patient.
All Pathology Reference Lab pathologists perform histology / histopathology.