Cervical Cancer Flashcards
What is ectropion?
Why does it occur?
- during puberty, rising levels of oestrogen cause the cervix to evert
- the columnar tissue lining the cervical canal is everted onto the surface of the cervix
- the area of columnar tissue in the centre of the cervix is known as ectopy / ectropion
What is the transformation zone?
How is it related to ectropion?
- the columnar cells on the surface of the cervix undergo squamous metaplasia
- this is a normal process caused by acidic conditions in the vagina
- the point where the columnar cells transform into squamous cells is the transformation zone
How might cervical intraepithelial neoplasia (CIN) develop?
- CIN can develop if oncogenic HPV affects the transformation zone
- CIN forms instead of normal squamous tissue
Where are samples taken from in cervical screening?
When can this be difficult?
- samples are taken from the transformation zone of the cervix
- this is more difficult in postmenopausal women
- the transformation zone is not visible with a speculum as it retracts
What is the most common cause of cervical cancer?
human papilloma virus (HPV)
- this is a sexually transmitted infection
- types 16 and 18 are responsible for 70% cervical cancers
- most cases of HPV resolve spontaneously within 2 years
it is also associated with anal, vulval, vaginal, penis, mouth + throat cancers
What is the vaccination schedule against HPV?
- 12- and 13- year old girls are offered a bivalent vaccine against HPV 16 + 18
- this prevents 90% genital warts and 60-70% CIN
What are the risk factors for cervical cancer associated with increased risk of catching HPV?
- unprotected sex
- sexually active from a young age
- multiple sexual partners
- sexual partners who have had more partners
What is the biggest risk factor for cervical cancer?
non-engagement with cervical screening
- many cases of cancer are preventable with early detection + treatment of precancerous changes
What are the other risk factors associated with cervical cancer?
- smoking
- HIV (immunosuppression)
- COCP use for > 5 years
- increased number of full term pregnancies
- family history
- exposure to diethylstilbestrol during fetal development (used prior to 1971)
people with HIV are offered yearly smear tests due to increased risk
What are the presenting symptoms that may be associated with cervical cancer?
- abnormal vaginal discharge (persistent, offensive, blood-stained)
- abnormal bleeding (PCB, PMB or IMB)
- dyspareunia
- pelvic pain (late disease)
many of these symptoms are non-specific and NOT caused by cancer
PCB = post-coital bleeding
IMB = intermenstrual bleeding
PMB = post-menopausal bleeding
If someone presents with cancer-associated symptoms, what should be done?
speculum examination
- this allows visualisation of the cervix
- swabs can be taken to exclude infection
this should be followed by bimanual and PR examination
What signs on speculum examination are red flags?
- ulceration
- inflammation
- bleeding
- visible tumour
- if any of these are seen, an urgent 2WW referral for colposcopy should be made
What is involved in a cervical smear test?
- a speculum is inserted and a small brush is used to collect cells from the transformation zone of the cervix
- this aims to pick up precancerous changes (CIN) in the cervical epithelial cells
- the cells are deposited in preservation fluid
- they are examined under a microscope for dyskaryosis
Before the cells from the smear test are examined microscopically, what is done?
- the cells are initially tested for high-risk HPV
- if this is negative, the cells are not examined
- the woman is returned to the routine screening programme
Who is offered cervical screening?
- every 3 years aged 25-49
- every 5 years aged 50-65
- women > 65 can request a smear test
How is dyskaryosis assessed?
- nuclear enlargement
- variation in size / shape of the nuclei
- hyperchromasia
- reduction in cytoplasm, altering the nuclear:cytoplasmic ratio
hyperchromasia - the nuclei appear dark / smudged / opaque when stained
What else may be detected / reported on the smear result?
- trichomonas
- candidiasis
- bacterial vaginosis
- actinomyces-like organisms in women with an intrauterine device
What are the 4 different potential outcomes of a smear test?
inadequate sample:
- repeat smear after at least 3 months
HPV negative:
- continue routine screening
HPV positive with normal cytology:
- repeat HPV test in 12 months
HPV positive with abnormal cytology:
- refer for colposcopy
What is cervical intraepithelial neoplasia?
- a grading system for the level of dysplasia (premalignant change) in the cells of the cervix
- this is diagnosed at colposcopy, and not on screening
- dysplasia is found during colposcopy
- dyskaryosis is found on cervical smear test
What is meant by CIN I?
mild dysplasia
- this affects 1/3 thickness of the epithelial layer
- likely to return to normal without treatment
- when confined to the epithelial layer, this is a pre-invasive change
- it becomes cancer when it invades below the epithelial layer
What is meant by CIN II?
moderate dysplasia
- this affects 2/3 thickenss of the epithelial layer
- likely to progress to cancer if not treated
What is meant by CIN III?
severe dysplasia
- this affects the whole epithelial layer
- very likely to progress to cancer
- sometimes called cervical carcinoma in situ
What is involved in colposcopy?
- a speculum is inserted and a colposcope is used to magnify the cervix
- the whole transformation zone is examined
- stains - aceitic acid and iodine solution - are used to differentiate abnormal areas
Why is acetic acid used and what is a positive result?
- abnormal cells will stain white (acetowhite)
- this occurs in cells with increased nuclear-to-cytoplasmic ratio
- e.g. CIN / cervical cancer
What is involved in Schiller’s iodine test?
- an iodine solution is used to stain the cervix
- healthy cells will stain brown
- abnormal areas will not stain
How is a biopsy taken during colposcopy?
- a punch biopsy
- or a large loop excision of the transformational zone (LLETZ)
What is involved in a large loop excision of the transformational zone (LLETZ)?
- local anaesthetic is given during colposcopy
- a loop of diathermy wire is used to remove abnormal epithelial cells
- the electrical current cauterises the tissue to prevent bleeding
What advice is given to women following a LLETZ procedure?
- bleeding / abnormal discharge can occur for several weeks following the procedure
- avoid tampon use / sexual intercourse due to increased infection risk
- increased risk of preterm labour
What is involved in a cone biopsy?
- a cone-shaped piece of the cervix is removed using a scalpel
- the sample is sent for histology to assess for malignancy
- this can lead to pain, bleeding and infection
- scar formation can lead to stenosis of the cervix
- increased risk of miscarriage / preterm labour
How common is cervical cancer and what is the survival like?
- 12th most common cancer in women
- most common in women under 35
- 67% 5-year survival
- 90% survival in women < 40
uterine and ovarian cancers are more common
What other organs does cervical cancer tend to spread to?
direct / local spread:
- vagina
- bladder
- parametrium
- bowel
bloodborne spread:
- lungs + liver
What lymph nodes does cervical cancer tend to spread to?
- parametrial nodes
- internal, external + common iliac nodes
- obturator nodes
- pre-sacral nodes
- para-aortic nodes
What staging system is used for cervical cancer?
international federation of gynaecology and obstetrics (FIGO) staging system
What are the 4 stages of cervical cancer according to FIGO?
stage 0:
- carcinoma in-situ / CIN
stage I:
- confined to the cervix
stage II:
- invades upper 2/3 of vagina or uterus
stage III:
- invades pelvic wall or lower 1/3 of vagina
stage IV:
- invades bladder, bowel or beyond the pelvis
What is the management for early stage cervical cancer?
- radical hysterectomy with removal of local lymph nodes
- this is followed with chemotherapy + radiotherapy
- if women require future fertility, cone biopsy can be repeated with pelvic node dissection
What is the current vaccination programme for HPV?
- it is given to all girls and boys around the age of 12-13
- this is before they become sexually active
- strains 6 and 11 cause genital warts
- strains 16 and 18 cause cervical cancer
