1- Introduction of Cytopathology

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Definition of cytopathology

Cytopathology is the study of normal and abnormal

exfoliated cells in tissue fluid.

The individual cells reflect the normal and abnormal

morphology of the tissue from which they are derived.

Types of exfoliated cyto-pathology

Natural spontaneous exfoliationNatural covering epithelium: skin, urinary tract, vagina, and

cervix.

Glandular epithelial secretion: Breast (Nipple secretion).

Sputum

Urine

Exudates and transudate:

Pleural fluid Peritoneal fluid

Pericardial fluid Joint fluid CSF

Artificial enhanced exfoliation:

Scrapings from cervix, vagina, oral cavity, and skin

Brushing and lavage: bronchi, GIT, and urinary tract

Fine needle aspiration (FNA) for:

Body cavity fluid: pleural, pericardial & peritoneal fluids

Cysts: neck, breast & ovary

Solid tissue: body organs, tumors & other swell

Role of cytopathology

Early detection of unsuspected diseases (malignant

or pre-malignant lesions).

Confirmation of suspected diseases without surgical

trauma.

Diagnosis of hormonal imbalance.

Useful in flow up the course of disease or monitoring

therapy.

Advantage of Cytopathology

Rapid diagnosis - Inexpensive - Simple

It is better in evaluating the infectious diseases.

Supplement or replace frozen section or biopsy

No injury to tissue allowing repeated sampling

It is better for hormonal assay

Cytopathological smear cover a wider surface than

that involved in surgical biopsy.

Disadvantage of Cytopathology

Interpretation of the morphological cellular changes is

based only on individual cell observation.

Not always finally diagnosis, so it is confirmed by

histopathology in some cases.

Not determine the size and type of lesion of some cases.

Factors that determine the appearance of cells

Type of the technique used.

Level of cell maturation at the time of cell collection.

Nature of the parents tissue: soft tissue, cyst, or solid organ.

Medium of the exfoliated cells.

Interval between the stain of the exfoliated cells and collection

of samples.

Type of fixative, stain, and processing of the technique used.

PAP smear: named afterDr. George Papanicolaou (1883-1962)

Vaginal smears from guinea pigs (1917)  Women (1920)

Hormonal cyclesPathological conditions (1928)

Normal Cervix

Taking the Sample

 Liquid Based Cytology – lab processing

Cytologic screening for cervical cancer

Cervical cancer screening has decreased morbidity and

mortality

Deaths from cervical cancer decreased from 26,000 to

less than 5,000 between 1941 and 1997

Pap smears are not perfect

For a high grade lesion, the sensitivity of a single pap

smear is only 60-80%

Estimated false negative rate is 30-50%

Requires adequate specimen collection

Requires adequate cytological review

Requires adequate patient and physician follow-up

10% of women with cervical cancer had inappropriate

follow-up.

Requires access to care

50% of women with cervical cancer were never screened

and 10% had not been screened within 5 years of

diagnosis.

Who to screen

Any woman with a cervix who has ever had sexual

activity.

When to screenStart within 3 years of onset of sexual activity or by age of

21, whichever is first.

Risk factors for cervical dysplasia

Early onset of sexual activity

Multiple sexual partners

Tobacco

Oral contraceptives

Screening frequency

Yearly until three consecutive normal pap smears, then

may decrease frequency to every three years

Annual screening for high-risk women is highly

recommend.

When to stop routine screening

Age 65 and “adequate recent screening”

Three consecutive normal pap smears

No abnormal pap smears in last 10 years

No history of cervical or uterine cancer

Hysterectomy for benign disease

Hysterectomy for invasive cervical cancer

Original Squamous Epithelium

Vagina and outer ectocervix

4 cell layers

Well-glycogenated (pink) unless atrophic

Columnar Epithelium

Upper and middle endo-cervical canal

Single layer of columnar cells arranged in folds

Mucin producing (not true glands)

Squamous Metaplasia

Central ectocervix and proximal endocervical canal

Replacement of columnar cells by squamous epithelium

Progressive and stimulated by

Acidic environment with onset of puberty

Estrogen causing eversion of endocervix

Transformation Zone

Zone between original squamo-columnar junction

and the “new” squamo-columnar junction

Nabothian cysts visually identify the transformation

zone if present

Original Squamo-columnar Junction

Placement determined between 18-20 weeks gestation

Most often found on ectocervix

Can be found in vagina or vaginal fornices

Less apparent over time with maturation of epithelium

“New” Squamo-columnar Junction

Border between squamous epithelium and columnar

epithelium

Found on ecto-cervix or in endo-cervical canal

Majority of cervical cancers and precursor lesions

arise in immature squamous metaplasia, i.e. the

leading edge of the squamo-columnar junction

Squamous Epithelium

Parabasal Cells

Intermediate Cells

Superficial Cells

Endocervix

Endocervical Cells

Endometrial Cells

Non-Epithelial Cells

sperms

Lymphocytes Polymorphs

Normal smear

Ectropion / ErosionAt puberty & pregnancy the endocervical cells are

pushed out to lie on the ectocervix

Normal Ectropion

Wide Ectropion

 

Metaplasia

The endocervical cells are transformed into squamous

cells through the process of squamous metaplasia

Metaplastic Cells