dysplasia
Meaning of dysplasia: Pathologists grade this finding from mild to severe, and the grade, not the label alone, carries most of its meaning.
Definition of dysplasia
Dysplasia is the presence of cells that look abnormal in size, shape, or arrangement when tissue is examined under a microscope, without meeting the criteria for cancer. The cells are no longer entirely normal, yet they lack the invasive behavior that defines a malignant tumor. The word also names abnormal development of a whole organ or body part.
How dysplasia is built
- dys- Prefix · Greek difficult, painful, disordered
- -plasia Suffix · Greek formation, growth, development
A medical term is read from its ending backwards: the suffix first, then the prefix, then the root. See all 223 word parts.
How is dysplasia graded?
Dysplasia is described along a range rather than as a single yes or no finding. A pathologist judges how irregular the cells look, how much of the tissue thickness is involved, and how many cells are in the act of dividing. Those observations are condensed into a grade, and the grade carries most of the practical meaning of the report. Mild changes involve a small part of the tissue and often settle once whatever irritated it is gone. Severe changes involve most of the tissue and are followed more closely, because the chance of progression rises with grade. Many reporting systems have collapsed the older three-step scale into two tiers, low grade and high grade, since two pathologists agree with each other far more often when the choice is simpler.
Where does it sit between normal tissue and cancer?
| Finding | How the cells look | Do they invade? |
|---|---|---|
| Normal tissue | Uniform cells in orderly layers | No |
| Dysplasia | Irregular in size and shape, disordered arrangement | No |
| Carcinoma in situ | Severely abnormal through the full thickness | No, the boundary layer is still intact |
| Invasive cancer | Abnormal cells pushing past the boundary | Yes |
The boundary that matters is the basement membrane, a thin sheet lying under the surface layer of cells. Dysplastic cells stay above it. Once cells cross it they can reach blood and lymph vessels, and that crossing is what separates cancer from every finding above it in the table. Dysplasia is not a stage of cancer and not a fixed diagnosis. Mild dysplasia commonly regresses, severe dysplasia does not always progress, and either is often followed over time with repeat sampling or imaging to see which way it moves.
Does the word always mean abnormal cells?
No. Dysplasia also names abnormal development of a whole structure, the older and broader sense of the term. Hip dysplasia describes a socket that formed too shallow to hold the thigh bone securely. Bronchopulmonary dysplasia describes lung tissue that developed abnormally in infants born very early. Neither has anything to do with a report from a microscope. Context settles which sense applies: a biopsy report means the cellular one, while an orthopedic or newborn note usually means the developmental one.
Used in a sentence
Biopsy results showed moderate dysplasia in the tissue sample obtained during the procedure.
Good to know
Dysplasia is not cancer, since the abnormal cells have not acquired the invasive behavior that defines a malignant tumor, though higher grade dysplasia is followed more closely because of the greater risk associated with it.
Word origin
Where “dysplasia” comes from
Formed from dys-, Greek for difficult or abnormal, and -plasia, from plassein, meaning to form or mold, together describing abnormal formation of tissue.