2: Cervical screening and vulval pathology Flashcards
Which type of epithelium lines the vaginal end of the cervix?
Squamous epithelium
What is the vaginal end of the cervix called?
Ectocervix
What is the uterine end of the cervix called?
Endocervix
Which type of epithelium is found in the endocervix?
Columnar, glandular epithelium
What is the transformation zone of the cervix?
Transition between squamous (vaginal end; ectocervical) and columnar (uterine end; endocervical) epithelium
Where does cervical cancer arise?
Squamo-columnar junction / Transformation zone
What causes the squamo-columnar junction to rise?
Menarche
Pregnancy
Menopause
The vagina is an (acidic / alkaline) environment.
acidic
What process occurs when the endocervix is opposed to the acid of the vagina?
Squamous metaplasia
Inflammation causes columnar epithelium to change into squamous epithelium
What is cervicitis?
Inflammation of the cervix
Which sexually transmitted infection, causing cervicitis, can lead to infertility?
Chlamydia
What is a cervical polyp?
Abnormal inflammatory growth in the cervix
Are cervical polyps malignant?
No
And most don’t become malignant
What is CIN?
Cervical intraepithelial neoplasia
Precursor to cervical cancer
What are the two most common forms of cervical cancer?
Squamous carcinoma
Adenocarcinoma
Which specific viruses are associated with a percentage of cervical cancers?
HPV 16
HPV 18
Which percentage of cervical cancers are caused by HPV 16 & 18?
70 - 75%
This means that 25 - 30% aren’t and you have to stay vigilant
What are risk factors for cervical cancer?
HPV infection (particularly 16 and 18)
Long-term oral contraceptive use
Smoking (big one)
Immunosuppression
What is a sign of HPV infection on histology?
Koilocytosis
Dyskaryosis (nuclear abnormalities) in an epithelial cell, giving them a HALO appearance
What causes CIN to be reclassified as cancer?
Breaks through basement membrane
What is the pre-invasive stage of cervical cancer called?
Cervical intraepithelial neoplasia (CIN)
Is CIN symptomatic?
No
Not visible to the human eye
By which process do the nuclei of cervical cells become enlarged, signalling CIN?
Koilocytosis
What are some nuclear signs of CIN?
Hyperchromasia - stain dark black
Increased nucleus:cytoplasm ratio
Pleomorphism - variable appearance between cells
How is CIN classified?
CN I - III
more invasive as you go up
What is CIN III also known as?
“Carcinoma-in-situ”
Impending malignancy
At which layer of squamous epithelium should mitosis be occurring?
Basal layer
If it’s happening above this then suspect CIN
What is the most common type of cervical cancer?
Squamous carcinoma
Why isn’t squamous carcinoma as common in the UK as it used to be?
Cervical screening program
Why can’t every cervical cancer be prevented by HPV vaccination?
Vaccinated HPV subtypes (6, 11, 16 and 18) only responsible for around 70% of cancers
What are the symptoms of high stage cervical cancer?
Abnormal bleeding
Pelvic pain
Renal symptoms (suggests obstruction of ureters)
Red flag cancer symptoms - fever, night sweats, unexpected WL
What investigations are done for suspected cervical cancer?
Cervical screening (to catch dysplasia early)
If abnormal, refer for Colposcopy
If high stage, MRI pelvis / other scans to look for metastasis
Which precursors of cervical cancer develop from the
a) ectocervix
b) endocervix?
a) CIN (cervical intraepithelial neoplasia)
b) CGIN (cervical GLANDULAR intraepithelial neoplasia)
Which invasive forms of cervical cancer develop from the
a) ectocervix
b) endocervix?
a) Squamous carcinoma
b) Adenocarcinoma
Which risk factor causes most cases of cervical cancer?
HPV infection
Which skin disease is implicated in vulval intraepithelial neoplasia (VIN) seen in older women?
Lichen sclerosus
Why is VIN a sinister diagnosis?
Vulva is closely associated with superficial inguinal nodes
So spread occurs easily
Which rare skin disease presents as a red, crusting rash and signals the presence of glandular tumours in the epidermis of the vulva?
Paget’s disease
different from the bone one
What is dyskaryosis?
Nuclear abnormalities in a cell, e.g
pleomorphism, high nucleus:cytoplasm ratio, hyperchromatosis (dark staining)
caused by acid damage, HPV infection, i.e damage to the cell
What is koilocytosis?
Dyskaryosis of an epithelial cell due to HPV infection
What does a koilocyte look like?
Darkly stained halo cell
What is a Nabothian cyst?
A cyst formed when ectocervix (squamous) grows over the top of endocervix (columnar)
Which lifestyle factor is highly associated with cervical cancer?
Smoking
How long does it take for initial HPV infection to develop into high-grade CIN?
Up to 3 years
How long does it take for high grade CIN to develop into invasive cervical cancer?
Up to 20 years
CIN classification depends on the ___ of epithelium occupied by abnormal cells.
thickness
CIN I - one third, CIN II - two thirds, CIN III - full thickness, impending malignancy
Which type of pre-malignant tumour arises from the endocervix?
Endocervix is made up of columnar glandular epithelium
So it develops CGIN (cervical glandular intraepithelial neoplasia)
Which can develop into adenocarcinoma
Which forms of cervical cancer are most common?
Squamous carcinoma (75%)
Adenocarcinoma (5-25%)
