Cervical screening and cancer Flashcards
Where is HPV infection and CIN seen in screening?
Transformation zone of cervix
Who is the peak incidence of HPV in?
15-25 year olds
What % of cervical cancers are associated with HPV?
> 99%
What % anal cancers are associated with HPV?
90%
What is the progression of HPV causing changes?
Early infection may be accompanied by mild changes in the epithelium
Abnormal growth of squamous cells detectable on smear- squamous intraepithelial lesion
Abnormal cells in cervix detected by biopsy and histological examination- classified as CIN
What HPV is highest risk for developing cancer?
16
What does th HPV vaccine vaccinate against?
6, 12, 16, 18
Who is cervical screening given to?
25-49 year olds every 3 years
50-64 every 5 years
What is the cervixal smear looking for?
High risk HPV DNA or RNA
How is the HPV test done?
Hybridisation
PCR
When is cervical cytology done?
If HPV +
What is cervical cytology?
Microscopic assessment of cells scraped from transformation zone
What does cervical cytology look for?
Abnormal cells- dyskaryosis
What causes CIN?`
Persistent HPV infection
What are the grades of CIN?
1- low grade, will regress
2- moderate dysplasia, may regress
3- severe dysplasia, unlikely to regress, precursor to cancer
What is the treatment of CIN?
LLETZ (excision)
Thermal coagulation
Laser ablation
What is the followup of CIN treatment?
Confirm treatment effective
Prevent invasive cancer and monitor for further cancer
Reassure woman
What are the majority of cervical cancers?
Squamous carcinomas
SOme adenocarcinomas
What is the staging of carvical cancer?
1- a- <5mm depth by <7mm diameter b- Confined to cervix 2- spread to vagina 3- lower vagina, pelvis 4- bladder, retum
Where does lymphatic spread of cervical cancer go?
Pelvic nodes
Where does cervical cancer metastasise?
Liver
Lungs
Bone
Who age is cervical cancer mostly seen in?
45-55
What HPV infections cause cervical cancer?
16 and 18
What are the risk factors for cervical cancer?
Multiple partners
Early age at first intercourse
Older age of partner
Cigarette smoking
