Module 7 - Gynae Cytopathology Flashcards
What is Diagnostic Cytopathology?
The interpretation of cellular changes related to benign, inflammatory and neoplastic conditions
Assessment of single cells or cell aggregates without the typical architectural landmarks usually observed
When should a Cervical Smear be conducted?
Midcycle
Absence of inflammation
1st smear depends on the age of initial sexual activity or at 25 years
Symptomatic women
- family history of cervical cancer
- abnormal looking cervix (discoloured, uclerated, tumor etc.)
- abnormal bleeding
When should a Cx Screening Test be Done?
Women with history of low risk HPV will have screening test every 5 years
Women with current or previous abnormality
Cervical screening can cease after 74 years of age if a women has had at least 2 negative oncogenic HPV tests
Women aged 70-74 who have opposite oncogenic variant, should be referred for colposcopic assessment with reflex LBC
Reflex Cytology
Done after detection of oncogenic HPV in primary screening
Cytology after detection of HPV in collect sample
Reflex LBC after detection of oncogenic HPV in FU HPV test
Cytology at colposcopy where:
- LBC unsat
- unconfirmed/untreated HSIL with gynae surveillance
What is considered Primary Screening?
Colposcopy today normal/unsat PV discharge Contact bleeding/heavy bleeding Menorrhagia/amenorrhoea/dysmenorrhoea Ectropion Inflamed cervix Endometrial thickening
What do you need for a Cervical Test?
Bivalve vaginal specimen Adjustable light Cervex sampler or endocervical spatula/broom Microscope slide with a frosted tip LBC collection system
Techniques for taking Cervical Samples
Cx sampler broom - rotate 3-5 times
and
Endocervical brush - insert into os, make sure can see lower row of bristles, make a quarter rotation
Cervix-Brush combi - insert central part of the brush into os and rotate clockwise twice
Spatula - rotate once or twice, be sure to keep in contact with ecto-cervix
and
Endocervical brush - insert into os, make sure can see lower row of bristles, make a quarter rotation
ThinPrep Sample Preparation Process
- Dispersion - rotation of filter in sample to separate debris and mucous
- Cell collection - vacuum is created which collects the cells on the exterior surface of the membrane
- Cell transfer - cells collected on membrane adhere to slide resulting in even distribution in an area
Anatomy - Vulva
Labia majora
Labia minora
- many sebaceous and apocrine sweat glands
Keratinising squamous eptihelium
Anatomy - Vagina
Fibromuscular structure extends from the cervix to the external genitalia
Does not contain glands
Lined by stratified squamous epithelium
Its wall consists of an inner mucosa, a middle muscularis layer and an
outer connective tissue adventitia
It is subjected to cyclical changes under influence of sex hormones
Anatomy - Cervix
Located in the lower part of the uterus and projects into the vaginal canal as the portio vaginalis.
Endocervical canal connects the body of the uterus at the internal os with the vagina at the external os
Ectocervix is the outer aspect of the cervix covered by squamous epithelium
Endocervical canal contains tall columnar cells with inconspicuous reserve cell layer underneath it
Squamo-columnar junction is where the squamous epithelium of the cervix meets the endocervical canal
Histology of the Cervix
All below are layers of the squamous epithelium
Germinal layer adheres to basement membrane
- single layer of small regular cells called basal cells
Parabasal layer is immature and crowded
- 2-3 cells deep
Intermediate layer shows variable thickness
- cells held together by intercellular bridges
Superficial layer has weaker cell bonds
- cells are dead or dying
- cell exfoliate spontaneously
Keratinsing layer
- layer of keratinised cells with a nucleus showing karyorrhexis and karyolysis
Histology of the Endocervical Canal
Part of the cervix might I add
Lined with tall, mucous secreting columnar epithelium
Lines highly branched and tubular cervical glands that extend into the cervical canal and into the lamina propria
Principle of the Papanicolaou Stain
Polychromatic stain with multiple dyes
Nuclei stained blue with Harris Hematoxylin
- Harris Hx is natural dye that has a high affinity for chromatin, attaching itself to sulphate groups on the DNA molecule
- Hx is not a stain, it is the oxidation product, haematein which is produced naturally or chemically using sodium iodate
Orange green 6 stains cytoplasm of mature and keratinised squamous cells
- OG6 is the first acidic counterstain used and structures stain orange with different intensities
Eosin Azure gives mature squamous cells the pink colour
- light green in EA50 stain the cytoplasm of metabolically active cells, like parabasal cells, intermediate squamous cells and columnar cells
Morphology of Basal Cells
Small cells that give rise to squamous cells Rarely recognised in a Pap smear Seen in short rows Sparse green cytoplasm Oval nuclei High N/C ratio Fine granular chromatin pattern Small chromocentres
