Lecture 21: Tumours of the reproductive tracts Flashcards
Are vulval cancers common?
No, 3% of all female cancers
-arise in older patients (80-84)
What is the most common cancer seen in the vulva?
The vulva is skin, so they are skin cancers
- squamous cell carcinoma (commonest)
- basal cell carcinoma
- malignant melanoma
What do vulval cancers appear as?
-lumps/bumps
-ulcerations
-pigmentation changes
-changes in sensation
-pain
(may be a delay to presentation as in intimate region, so usually advanced)
Histologically: no distinct layers in the skin, cells are atypical
-squamous cell carcinomas produce keratin so will see swirls of spherical keratin formation
What is VIN?
Vulvar intraepithelial neoplasia (in situ- contained within the basal layer)
- precancerous skin condition
- may progress to squamous cell carcinoma
Does HPV cause VIN and vulval squamous cell carcinoma?
-in 30% of cases, HPV16 does cause it
-im majority of cases, HPV does not relate to VIN and VSCC
(they are related to long standing chronic inflammatory conditions)
How do malignant cells spread?
- direct extension
- lymphatic vessels
- blood vessels
Where do vulval cancers commonly spread to?
Lungs and liver
What are the parts of the cervix?
Ectocervix: incommunication with the vagina (acidic environment so it stratified squamous epithelia)
Endocervix: not in contact with the vagina, epithelial lining is simple columnar
At mestruation, oestrogen causes: evertion (pushes outwards), so simple columnar epithelium is now exposed to the acidic vagina: get inflammation
-simple columnar cells undergo metaplasia to become stratified squamous= TRANSFORMATION ZONE
-metaplasia good in short term but increases risk of dyplasia
What does HPV cause?
HPV is sexually transmitted
Low risk HPV (6 and 11): warts
High risk HPV (16 and 18): lead to cancer, preferentially infects the transformation zone, produce viral proteins e.g. E6/7, inactive tumour suppressor genes (6: p53, 7: retinoblastoma gene)
What is CIN?
Cervical intraepithelial neoplasia
- dysplasia confined to the cervical epithelia (in situ), no breaking through the basement membrane
- if they do break through the membrane=invasion: invasive squamous cell carcinoma
- HPV causes CIN
What are the classifications of CIN?
1 (bottom 1/3), 2 (2/3rds), 3 (full thickness)
-determined by the thickness of the cervical epithelium that is dyplastic
What are the risk factors for CIN and cerivcal squamous cell carcinoma?
- HPV (multiple sexual partners, early intercourse increase risk of HPV exposure)
- early first pregnancy
- multiple births
- low socio-economic status
- smoking
- immunosuppression
How do you treat CIN?
- CIN1 often regresses spontaneously
- CIN2 and 3 denote risk of developing into squamous cell carcinoma
- urgent colcoscopy (look at cervix)
- can remove transformation zone
When des the cervical cancer screening programme start?
24 1/2, every 3/5 years
- brush used on transformation zone
- cells sent to cytology (tested for HPV, if positive the cells undergo microscopy, if negative they go back to routine follow up)
-vaccination available now and targets the most common high risk subtypes of HPV, given at age of 12-14
What other types of cancers can HPV cause?
Oral and anal cancers (why men also have the vaccine)