Cervical Cancer Flashcards
What cells line the endocervix?
Columnar epithelial cells that produce mucus.
What cells line the ectocervix?
Squamous epithelial cells.
Where is the transformation zone?
At the squamocolumnar junction where the endo and ectocervix meet.
Explain metaplasia at the squamocolumnar junction.
Columnar epithelial cells undergo metaplasia and transform into squamous epithelial cells.
Where does cervical intraepithelial neoplasia begin?
In the basal layer of the transformation zone.
What is the biggest risk factor for cervical cancer?
HPV (16&18)
How does HPV cause cervical cancer?
HPV blocks the action of tumour supressor genes namely P53. This results in uncontrolled replication of cervical epithelial cells which are resistant to apoptosis.
Explain the grading of cervical neoplasia.
CIN 1 - affects the lower one third of the epithelium.
CIN 2 - affects two thirds.
CIN 3 - affects virtually all of the cervical epithelium.
Carcinoma in situ
Invasive cervical cancer
What type are the majority of cervical cancer?
Squamous cell carcinomas
Why are squamous cell carcinomas the most common form of cervical cancer?
The squamous cells of the cervix are affected by dysplasia first.
Dysplasia
Dysplasia refers to the abnormal development of cells within tissues or organs. It can lead to a wide range of conditions that involve enlarged tissue or pre-cancerous cells.
What is the second most common form of cervical cancer?
Cervical adenocarcinoma - epithelial gland cells of the cervix.
Note: HPV to cervical cancer has a slow progression and can take between 10-20 years.
Note: HPV to cervical cancer has a slow progression and can take between 10-20 years.
Which patient group is at high risk for HPV?
HPV is a STI so women that have multiple sexual partners and do not use condoms.
What are risk factors for HPV?
Type of HPV
Length of infection
Immunocomprimised
Smoking
Preventative measure for HPV.
HPV vaccine which protects against HPV 16&18 the strains that have been linked to causing cervical cancer.
What are the symptoms of cervical cancer?
Abnormal vaginal bleeding (especially after sexual intercourse).
Vaginal discomfort.
Vaginal discharge with unpleasant smell.
Pain when urinating.
What are signs of metastasis of cervical cancer?
Constipation
Bloody urine
What is the screening and prevention available for cervical cancer?
Pap smear (recommended one smear every 3 years for females between 21 and 65). HPV vaccine.
What is the follow up for a pap smear that shows dysplasia?
Colposcopy and cervical biopsy.
Colposcopy
Endoscopy of the cervix
What causes the metaplasia of the cervix.
Metaplasia is thought o be a reaction of columnar epithelium to the acidic vaginal environment (during the reproductive years).
Metaplasia
The reversible transformation of one differentiated cell into another differentiated cell.
Neoplasia
Neoplasia is the presence or formation of new, abnormal growth of tissue.
CIN’s
Cervical intraepithelial neoplasia’s - they are the precursors of cervical cancer.
HPV
Human papilloma virus
What are the proteins that HPV produces that cause cervical cancer?
E6 and E7 which stimulate the continued proliferation of cells.
What does E6 do?
E6 promotes degradation of p53 protein leading
to the inhibition of apoptosis and cell cycle
arrest.
What does E7?
E7 promotes degradation of Rb protein leading
to the promotion of cellular proliferation.
What % of cervical cancer cases in the UK are caused by HPV infection?
99.8% of cervical cancer cases in the UK are caused by HPV infection.
What are the two HPV vaccines called?
Gardasil
Cervarix
Condyloma
Wartlike growths around the anus, vulva, or glans penis.
