L6 - Diagnostic Cytology Specimens,Theory & Gyn Cytology

Question 1

Why do we do cervical screens?

Answer 1

• Reduce the incidence of cervical cancer
• Screening guidelines differ at an international level from 1 to 5 years
• In Australia we used to screen every 2 years if a screen was negative
• as of Dec 2017, if a patient is HPV DNA neg for HR HPV, they will not require a HPV or reflex pap test for 5 years

Question 2

Renewal of the National Cervical Screening Guidelines

Answer 2

• 5 yearly cervical screening with HPV DNA and partial HPV genotyping with and without reflex LBC in vaccinated and unvaccinated women
• Self collection a HPV sample for underscreened women facilitated by a nurse or GP
• Invitations/reminders sent out to women aged 25 - 74 for screening
• Delisting of the existing cervical screening MBS items

Question 3

Sampling the cervix

Answer 3

Materials required:

• Cervex brush
• Wooden Ayre’s spatula
• Endocervical brush
• Most premalignant and malignant lesions occur in the transformation zone

Question 4

How conventional smears are prepared

Answer 4

• As soon as the smear is completed fix the slide in cytofix (2.5 PEG fixative)
• Fixed in 95% alcohol in a coplin jar
• Fixation should occur within 30 seconds to prevent drying out
• Cervical smears are always stained with the Papanicolau stain

Question 5

Papanicolau Stain

Answer 5

• A polychromatic stain uses multiple dyes to differentially stain different components of the cell
• includes both acidic and basic dyes
• haematoxylin stains the nucleus blue
• OG6 is the first acidic component and stains mature and keratinised cells, the target structures are stained orange
• EA50 is the second acidic counterstain and gives a pink colour to the cytoplasm of mature sqaumous cells, nucleoli and RBCs

Question 6

Preparation methods

Answer 6

• Conventional pap smears
• Liquid based samples
• Screening methods

Question 7

Liquid based methods

Answer 7

• thin prep samples

- surepath

Question 8

Screening methods

Answer 8

• cytologist - incorporates human error

- interactive automation (thin prep imaging system, focal point slide profiler)

Question 9

Vulva

Answer 9

• Labia majora
• Labia minora (many sebaceous and apocrine sweat glands)
• keratinising squamous epithelium

Question 10

Vagina

Answer 10

• Stratified non-keratinising squamous epithelium
• mucosa is subject to cyclical changed under the influence of sex hormones
• fibrovascular sheath
• no glands

Question 11

Uterus

Answer 11

• pear shaped organ
• body/corpus and cervix
• perimetrium (serosa)
• myometrium (smooth muscle)
• endometrium

Question 12

Cervix

Answer 12

• cylindrical fibromuscular structure
• endocervical canal connects the body of the uterus at the internal os with the vagina at the external os
• protrudes into the vagina - posterior, anterior, and 2 lateral fornices
• ectocervix is the other aspect of the cervix covered by squamous epithelium
• endocervical canal - tall columnar cells with inconspicous reserve cell layer underneath
• squamo-columnar junction is where the squamous epithelium of the cervix meets the endocervical canal

Question 13

Endocervical canal

Answer 13

• Tall mucus secreting columnar epithelial cells

- Highly branched tubular and cervical glanda

Question 14

Portio vaginalis

Answer 14

• Germinal layer: adheres to basement membrane
• Parabasal layer: immature and crowded
• Intermediate layer: variable thickness

Question 15

Endometrial histology

Answer 15

• Endometrium: thin basalis layer which is next to the myometrium
• the functional layer is superficial, compact layer has few glands and abundant stroma
• deep layer or spongiosa with abundant glands and less stroma

Question 16

Cytology of pap smears

Answer 16

• superficial squamous cells
• intermediate squamous cells
• parabasal cells
• endocervical cells

Question 17

Superficial squamous cells

Answer 17

• large polygonal
• slightly larger than intermediate cells
• pink or orange cytoplasm which is flat
• nuclei are small, central, pyknotic and have no internal structures

Question 18

Intermediate squamous cells

Answer 18

• polygonal in shape
• larger than parabasal cells
• cytoplasm is blue/green
• nucleus is round or oval with vesicles
• cells appear crowded or folded
• fine chromatin pattern

Question 19

Parabasal cells

Answer 19

• round/oval shaped cells
• fairly dense green cytoplasm
• may stain pink if not well preserved
• nucleus takes up half of cell
• fine chromatin pattern
• may be in sheets or separate cells
• commonly found in menopausal women or post partum

Question 20

Endocervical cells

Answer 20

• present in small sheets, in groups, or singly
• honeycomb arrangement
• delicate cytoplasm
• basally placed nucleus
• has nucleoli
• fine chromatin pattern
• mucin secreting goblet cells
• multinucleation
• cilia may be present

Question 21

Bacteria

Answer 21

• lactobacilli: normal flora
• bacterial vaginosis: clue cells
• actinomyces: organisms
• leptothrix species

Question 22

What we look for in CIN

Answer 22

• Absolute size of the cell
• Variability in nuclear size/shape (polymorphism)
• High nucleus to cytoplasm ration
• Irregular nuclear envelope
• Dark nuclear hyperchromasia
• Abnormal chromatin pattern

Question 23

Prognosis of cervical cancer

Answer 23

• 15 - 85% 5 year survival rate depending on tumour differentiation and stage