2. DYSPLASIA
• Dysplasia (dys-, "difficulty“ plasis, "formation") is a
an
abnormality of
development.
term used in pathology to refer to
3. • This generally consists of an
expansion of immature
cells (such as cells of the
ectoderm), with a corresponding
decrease in the
number and
location of mature
4. • Dysplasia is often indicative of
an early neoplastic process.
• The term dysplasia is typically used
when the cellular
abnormality is restricted
to the originating tissue,
as in the case of an
early, in-situ neoplasm.
5. Microscopic
changes
• Dysplasia is characterised by four major
pathological microscopic changes:
1.Anisocytosis (cells of unequal size)
2.Poikilocytosis (abnormally shaped cells)
3.Hyperchromatism (excessive pigmentation)
4.Presence of mitotic figures (an unusual number of
cells which are currently dividing).
6. • Dysplasia is an abnormality of both differentiation
and maturation.
• It is an alteration in adult cells characterized by
variation in their size, shape and organization.
• It is a loss of uniformity of cells and
loss in their structural
orientation.
• Dysplasia encountered principally in
epithelium.
7. The dysplastic cells show:
1. Pleomorphism: Variation in size & shape.
2. Increased nuclear cytoplasmic ratio: N= 1:5/1: 6
Increased size of nucleus causes increased nuclear cytoplasmic ration.
3. Hyperchromasia: Increased chromatin content resulting in deeply stained nuclei.
4. Increased mitotic figures: but pattern is normal
5. Cytoplasmic abnormalities: lack of keratinization in squamous
cells & lack of mucin in glandular epithelium.
6
. Disorderly arrangement of cells basal layer to the
surface layer.
8. • Dysplasia is associated with chronic
inflammation or irritation.
This is non-neoplastic proliferation
which differs from neoplasia in that
the growth of dysplastic cell is
controlled and stops when inciting
stimulus ceases while
the
growth of neoplastic cell is
uncontrolled that persists
even after the cessation of
the stimulus.
9. • Hyperplasia and metaplasia are not
directly premalignant condition, but if
they are severe and sustained, they
may progress to dysplasia which
carries the risk of conversion to
malignancy.
• Dysplasia carries the
high risk of conversion
to malignant
neoplasm.
11. Clinical Significance
• 1. Dysplasia is
reversible when
inciting stimulus is
removed.
• 2. Higher chances of
neoplastic
transformation.
12. Developmental Dysplasia
• It is a defective
development of cells and
tissues resulting in
abnormal or primitive
histiogenetic structure
e.g., renal dysplasia.
13. Dysplasia Harsh Mohan
• Dysplasia means ‘disordered cellular
development’, often accompanied with
metaplasia and hyperplasia.
• Dysplasia occurs most often in epithelial cells.
• Epithelial dysplasia is characterised by cellular
proliferation and cytologic changes.
14. Changes in dysplasia
• 1. Increased number of layers of epithelial cells.
• 2. Disorderly arrangement of cells from basal layer
to the surface layer.
• 3. Loss of basal polarity i.e. nuclei lying away from
basement membrane.
• 4. Cellular and nuclear pleomorphism.
• 5. Increased nucleocytoplasmic ratio.
• 6. Nuclear hyperchromatism.
• 7. Increased mitotic activity.
16. • Dysplastic changes often
occur due to chronic
irritation or prolonged
inflammation. On removal
of the inciting stimulus, the
changes may disappear.
17. • In a proportion of cases,
however, dysplasia
progresses into carcinoma
in situ (cancer confined to
layers superficial to
basement membrane) or
invasive cancer.
18. Dysplasia- SR
• Dysplasia is a disorderly but
non-neoplastic proliferation.
Dysplasia is encountered
principally in the epithelia. It
is a loss in the uniformity of
individual cells and in their
architectural orientation.
19. • Dysplastic cells exhibit considerable
pleomorphism and often possess
hyperchromatic nuclei that are
abnormally large for the size
of the cell.
• Mitotic figures are more abundant than
usual.
20. • Frequently the mitoses appear in
abnormal locations within the
epithelium.
• in dysplastic stratiFied squamous
epithelium, mitoses are not conFined to
the basal layers, where they
normally occur, but may appear at all
levels and even in surface cells.
21. • There is considerable architectural anarchy.
• For example, the usual progressive
maturation of tall cells in the basal layer
to flattened squames on the surface
may be lost and replaced by a
disordered scrambling
of dark basal
appearing cells.
22. • When dysplastic changes
are marked and involve
the entire thickness of
the epithelium, the lesion
is referred to as
carcinoma in situ, a preinvasive stage of cancer.
23. • Although dysplastic changes are often
found adjacent to foci of malignant
transformation, and long-term studies of
cigarette smokers show that epithelial
dysplasia almost invariably antedates
the appearance of cancer, the term
dysplasia without qualification does not
indicate cancer, and dysplasia do
not necessarily progress to
cancer.
24. • Mild to moderate changes
that do not involve the
entire thickness of
epithelium may be
reversible, and with
removal of the putative
inciting causes, the
epithelium may revert to
normal.
